Search for "Birch reduction" in Full Text gives 23 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2025, 21, 369–406, doi:10.3762/bjoc.21.27
Graphical Abstract
Scheme 1: Continuum in the mechanistic pathway of glycosylation [32] reactions ranging between SN2 and SN1.
Scheme 2: Formation of 1,2-trans glycosides by neighbouring group participation with acyl protection in C-2 p...
Scheme 3: Solvent-free activation [92] of disarmed per-acetylated (15) and per-benzoylated (18) glycosyl donors.
Scheme 4: Synthesis of donor 2-(2,2,2-trichloroethoxy)glucopyrano-[2,1-d]-2-oxazoline 22 [94] and regioselective ...
Scheme 5: The use of levulinoyl protection for an orthogonal glycosylation reaction.
Figure 1: The derivatives 32–36 of the pivaloyl group.
Scheme 6: Benzyl and cyanopivalolyl ester-protected hexarhamnoside derivative 37 and its global deprotection ...
Scheme 7: Orthogonal chloroacetyl group deprotection in oligosaccharide synthesis [113].
Figure 2: The derivatives of the chloroacetyl group: CAMB protection (41) [123], CAEB protection (42) [124], POMB prote...
Scheme 8: Use of the (2-nitrophenyl)acetyl protecting group [126] as the neighbouring group protecting group at th...
Scheme 9: Neighbouring group participation protocol by the BnPAc protecting group [128] in the C-2 position.
Scheme 10: Glycosylation reaction with O-PhCar (54) and O-Poc (55) donors showing high β-selectivity [133].
Scheme 11: Neighbouring group participation rendered by an N-benzylcarbamoyl (BnCar) group [137] at the C-2 positio...
Scheme 12: Stereoselectivity obtained from glycosylation [138] with 2-O-(o-trifluoromethylbenzenesulfonyl)-protecte...
Scheme 13: (a) Plausible mechanistic pathway for glycosylation with C-2 DMTM protection [139] and (b) example of a ...
Scheme 14: Glycosylation reactions employing MOM 78, BOM 81, and NAPOM 83-protected thioglycoside donors. Reag...
Scheme 15: Plausible mechanistic pathway for alkoxymethyl-protected glycosyl donors. Path A. Expected product ...
Scheme 16: Plausible mechanistic pathway for alkoxymethyl-protected glycosyl donors [147].
Scheme 17: A. Formation of α-glycosides and B formation of β-glycosides by using chiral auxiliary neighbouring...
Scheme 18: Bimodal participation of 2-O-(o-tosylamido)benzyl (TAB) protecting group to form both α and β-isome...
Scheme 19: (a) 1,2-trans-Directing nature using C-2 cyanomethyl protection and (b) the effect of acceptors and...
Scheme 20: 1,3-Remote assistance by C-3-ester protection for gluco- and galactopyranosides to form 1,2-cis gly...
Scheme 21: 1,6-Remote assistance by C-6-ester protection for gluco- and galactopyranosides to form 1,2-cis gly...
Scheme 22: 1,4-Remote assistance by C-4-ester protection for galactopyranosides to form 1,2-cis glycosidic pro...
Scheme 23: Different products obtained on activation of axial 3-O and equatorial 3-O ester protected glycoside...
Scheme 24: The role of 3-O-protection on the stereochemistry of the produced glycoside [191].
Scheme 25: The role of 4-O-protection on the stereochemistry of the produced glycosides.
Scheme 26: Formation and subsequent stability of the bicyclic oxocarbenium intermediate formed due to remote p...
Scheme 27: The role a C-6 p-nitrobenzoyl group on the stereochemistry of the glycosylated product [196].
Scheme 28: Difference in stereoselectivity obtained in glycosylation reactions by replacing non-participating ...
Scheme 29: The role of electron-withdrawing and electron-donating substituents on the C-4 acetyl group in glyc...
Scheme 30: Effect of the introduction of a methyl group in the C-4 position on the glycosylation with more rea...
Figure 3: Remote group participation effect exhibited by the 2,2-dimethyl-2-(o-nitrophenyl)acetyl (DMNPA) pro...
Scheme 31: The different stereoselectivities obtained by Pic and Pico donors on being activated by DMTST.
Figure 4: Hydrogen bond-mediated aglycon delivery (HAD) in glycosylation reactions for 1,2-cis 198a and 1,2-t...
Scheme 32: The role of different acceptor with 6-O-Pic-protected glycosyl donors.
Scheme 33: The role of the remote C-3 protection on various 4,6-O-benzylidene-protected mannosyl donors affect...
Scheme 34: The dual contribution of the DTBS group in glycosylation reactions [246,247].
Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214
Graphical Abstract
Figure 1: Classification of LSF reactions in this review.
Scheme 1: C(sp2)–H trifluoromethylation of heteroarenes.
Scheme 2: C(sp2)–H and C(sp3)–H alkylation of complex molecules.
Scheme 3: Electrochemical oxidation-induced intermolecular aromatic C–H sulfonamidation.
Scheme 4: Bioconjugation of tyrosine with (a) phenothiazine and (b) urazole derivatives.
Scheme 5: Electrochemical iodoamination of indoles using unactivated amines.
Scheme 6: Allylic C(sp3)–H aminations with sulfonamides.
Scheme 7: Electrochemical benzylic oxidation of C–H bonds.
Scheme 8: Site-selective electrooxidation of methylarenes to aromatic acetals.
Scheme 9: Electrochemical activation of C–H by electron-deficient W2C nanocrystals.
Scheme 10: α-Acyloxy sulfide preparation via C–H/OH cross-dehydrogenative coupling.
Scheme 11: Aromatic C–H-bond thiolation.
Scheme 12: C(sp2)–H functionalization for the installation of sulfonamide groups.
Scheme 13: Preparation of (hetero)aryl chlorides and vinyl chloride with 1,2-dichloroethane. aCu(OAc)2 (0.05 e...
Scheme 14: Electrochemical dual-oxidation enables access to α-chlorosulfoxides.
Scheme 15: Regio- and chemoselective formyloxylation–bromination/chlorination/trifluoromethylation of alkenes.
Scheme 16: Aziridine formation by coupling amines and alkenes.
Scheme 17: Formation of iminosulfide ethers via difunctionalization of an isocyanide.
Scheme 18: Synthesis of 1,3-difunctionalized molecules via C–C-bond cleavage of arylcyclopropane.
Scheme 19: Electrooxidative amino- and oxyselenation of alkenes. VBImBr = 1-butyl-3-vinylimidazolium bromide.
Scheme 20: Electrooxidative dehydrogenative [4 + 2] annulation of indole derivatives.
Scheme 21: Electrochemical cyclization combined with alkoxylation of triticonazole.
Scheme 22: Electrochemically tuned oxidative [4 + 2] annulation of olefins with hydroxamic acids.
Scheme 23: Electrosynthesis of indole derivatives via cyclization of 2-ethynylanilines.
Scheme 24: Allylic C–H oxidation of mono-, di-, and sesquiterpenes.
Scheme 25: Oxidation of unactivated C–H bonds.
Scheme 26: Fluorination of C(sp3)–H bonds. rAP = rapid alternating polarity.
Scheme 27: C(sp3)–H α-cyanation of secondary piperidines.
Scheme 28: Selective electrochemical hydrolysis of hydrosilanes to silanols.
Scheme 29: Organocatalytic electrochemical amination of benzylic C–H bonds.
Scheme 30: Iodide ion-initiated anodic oxidation reactions.
Scheme 31: Mn(III/IV) electro-catalyzed C(sp3)–H azidation.
Scheme 32: Tailored cobalt–salen complexes enable electrocatalytic intramolecular allylic C–H functionalizatio...
Scheme 33: Cobalt–salen complexes-induced electrochemical (cyclo)additions.
Scheme 34: Electrochemical 1,2-diarylation of alkenes enabled by direct dual C–H functionalization of electron...
Scheme 35: Cobalt-electrocatalyzed atroposelective C–H annulation.
Scheme 36: Nickel-electrocatalyzed C(sp2)–H alkoxylation with secondary alcohols.
Scheme 37: Nickel-catalyzed electrochemical enantioselective amination.
Scheme 38: Ruthenium-electrocatalyzed C(sp2)–H mono- and diacetoxylation.
Scheme 39: Rhodium(III)-catalyzed aryl-C–H phosphorylation enabled by anodic oxidation-induced reductive elimi...
Scheme 40: Asymmetric Lewis-acid catalysis for the synthesis of non-racemic 1,4-dicarbonyl compounds.
Scheme 41: Electrochemical enantioselective C(sp3)–H alkenylation.
Scheme 42: Palladium-catalyzed electrochemical dehydrogenative cross-coupling.
Scheme 43: Ir-electrocatalyzed vinylic C(sp2)–H activation for the annulation between acrylic acids and alkyne...
Scheme 44: Electrochemical gold-catalyzed C(sp3)–C(sp) coupling of alkynes and arylhydrazines.
Scheme 45: Photoelectrochemical alkylation of C–H heteroarenes using organotrifluoroborates.
Scheme 46: Mn-catalyzed photoelectro C(sp3)–H azidation.
Scheme 47: Photoelectrochemical undirected C–H trifluoromethylations of (Het)arenes.
Scheme 48: Photoelectrochemical dehydrogenative cross-coupling of heteroarenes with aliphatic C–H bonds.
Scheme 49: C–H amination via photoelectrochemical Ritter-type reaction.
Scheme 50: Photoelectrochemical multiple oxygenation of C–H bonds.
Scheme 51: Accelerated C(sp3)–H heteroarylations by the f-EPC system.
Scheme 52: Photoelectrochemical cross-coupling of amines.
Scheme 53: Birch electroreduction of arenes. GSW = galvanized steel wire.
Scheme 54: Electroreductive deuterations.
Scheme 55: Chemoselective electrosynthesis using rapid alternating polarity.
Scheme 56: Electroreductive olefin–ketone coupling.
Scheme 57: Electroreductive approach to radical silylation.
Scheme 58: Electrochemical borylation of alkyl halides. CC = carbon close.
Scheme 59: Radical fluoroalkylation of alkenes.
Scheme 60: Electrochemical defluorinative hydrogenation/carboxylation.
Scheme 61: Electrochemical decarboxylative olefination.
Scheme 62: Electrochemical decarboxylative Nozaki–Hiyama–Kishi coupling.
Scheme 63: Nickel-catalyzed electrochemical reductive relay cross-coupling.
Scheme 64: Electrochemical chemo- and regioselective difunctionalization of 1,3-enynes.
Scheme 65: Electrocatalytic doubly decarboxylative crosscoupling.
Scheme 66: Electrocatalytic decarboxylative crosscoupling with aryl halides.
Scheme 67: Nickel-catalyzed electrochemical reductive coupling of halides.
Scheme 68: Nickel-electrocatalyzed enantioselective carboxylation with CO2.
Scheme 69: Reductive electrophotocatalysis for borylation.
Scheme 70: Electromediated photoredox catalysis for selective C(sp3)–O cleavages of phosphinated alcohols to c...
Scheme 71: Stereoselective electro-2-deoxyglycosylation from glycals. MFE = methyl nonafluorobutyl ether.
Scheme 72: Electrochemical peptide modifications.
Scheme 73: Electrochemical α-deuteration of amides.
Scheme 74: Electrochemical synthesis of gem-diselenides.
Scheme 75: Site-selective electrochemical aromatic C–H amination.
Scheme 76: Electrochemical coupling of heteroarenes with heteroaryl phosphonium salts.
Scheme 77: Redox-neutral strategy for the dehydroxyarylation reaction.
Scheme 78: Nickel-catalyzed electrochemical C(sp3)–C(sp2) cross-coupling of benzyl trifluoroborate and halides....
Scheme 79: Paired electrocatalysis for C(sp3)–C(sp2) coupling.
Scheme 80: Redox-neutral strategy for amination of aryl bromides.
Scheme 81: Redox-neutral cross-coupling of aryl halides with weak N-nucleophiles. aProtocol with (+) RVC | RVC...
Scheme 82: Nickel-catalyzed N-arylation of NH-sulfoximines with aryl halides.
Scheme 83: Esterification of carboxylic acids with aryl halides.
Scheme 84: Electrochemically promoted nickel-catalyzed carbon–sulfur-bond formation. GFE = graphite felt elect...
Scheme 85: Electrochemical deoxygenative thiolation by Ni-catalysis. GFE = graphite felt electrode; NFE = nick...
Scheme 86: Electrochemical coupling of peptides with aryl halides.
Scheme 87: Paired electrolysis for the phosphorylation of aryl halides. GFE = graphite felt electrode, FNE = f...
Scheme 88: Redox-neutral alkoxyhalogenation of alkenes.
Beilstein J. Org. Chem. 2024, 20, 787–814, doi:10.3762/bjoc.20.72
Graphical Abstract
Scheme 1: Classes of hydrochlorination reactions discussed in this review.
Figure 1: Mayr’s nucleophilicity parameters for several alkenes. References for each compound can be consulte...
Figure 2: Hydride affinities relating to the reactivity of the corresponding alkene towards hydrochlorination....
Scheme 2: Distinction of polar hydrochlorination reactions.
Scheme 3: Reactions of styrenes with HCl gas or HCl solutions.
Figure 3: Normal temperature dependence for the hydrochlorination of (Z)-but-2-ene.
Figure 4: Pentane slows down the hydrochlorination of 11.
Scheme 4: Recently reported hydrochlorinations of styrenes with HCl gas or HCl solutions.
Scheme 5: Hydrochlorination reactions with di- and trisubstituted alkenes.
Scheme 6: Hydrochlorination of fatty acids with liquified HCl.
Scheme 7: Hydrochlorination with HCl/DMPU solutions.
Scheme 8: Hydrochlorination with HCl generated from EtOH and AcCl.
Scheme 9: Hydrochlorination with HCl generated from H2O and TMSCl.
Scheme 10: Regioisomeric mixtures of chlorooctanes as a result of hydride shifts.
Scheme 11: Regioisomeric mixtures of products as a result of methyl shifts.
Scheme 12: Applications of the Kropp procedure on a preparative scale.
Scheme 13: Curious example of polar anti-Markovnikov hydrochlorination.
Scheme 14: Unexpected and expected hydrochlorinations with AlCl3.
Figure 5: Ex situ-generated HCl gas and in situ application for the hydrochlorination of activated alkenes (*...
Scheme 15: HCl generated by Grob fragmentation of 92.
Scheme 16: Formation of chlorophosphonium complex 104 and the reaction thereof with H2O.
Scheme 17: Snyder’s hydrochlorination with stoichiometric amounts of complex 104 or 108.
Scheme 18: In situ generation of HCl by mixing of MsOH with CaCl2.
Scheme 19: First hydrochlorination of alkenes using hydrochloric acid.
Scheme 20: Visible-light-promoted hydrochlorination.
Scheme 21: Silica gel-promoted hydrochlorination of alkenes with hydrochloric acid.
Scheme 22: Hydrochlorination with hydrochloric acid promoted by acetic acid or iron trichloride.
Figure 6: Metal hydride hydrogen atom transfer reactions vs cationic reactions; BDE (bond-dissociation energy...
Scheme 23: Carreira’s first report on radical hydrochlorinations of alkenes.
Figure 7: Mechanism for the cobalt hydride hydrogen atom transfer reaction reported by Carreira.
Scheme 24: Radical “hydrogenation” of alkenes; competing chlorination reactions.
Scheme 25: Bogers iron-catalyzed radical hydrochlorination.
Scheme 26: Hydrochlorination instead of hydrogenation product.
Scheme 27: Optimization of the Boger protocol by researchers from Merck [88,89].
Figure 8: Proposed mechanism for anti-Markovnikov hydrochlorination by Nicewicz.
Scheme 28: anti-Markovnikov hydrochlorinations as reported by Nicewicz.
Figure 9: Mechanism for anti-Markovnikov hydrochlorination according to Ritter.
Scheme 29: anti-Markovnikov hydrochlorinations as reported by Nicewicz; rr (regioisomeric ratio) corresponds t...
Scheme 30: anti-Markovnikov hydrochlorinations as reported by Liu.
Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81
Graphical Abstract
Figure 1: Oxidative and reductive activations of organic compounds harvesting photoredox catalysis.
Figure 2: General catalytic cycles of radical ion conPET (left) and radical ion e-PRC (right).
Figure 3: “Beginner’s guide”: comparison between advantages, capacities, and prospectives of conPET and PEC.
Figure 4: A) conPET reductive dehalogenation of aryl halides with PDI. B) Reductive C–H arylation with pyrrol...
Figure 5: A) Chromoselective mono- and disubstitution or polybrominated pyrimidines with pyrroles. B) Sequent...
Figure 6: A) Synthesis of pyrrolo[1,2-a]quinolines. B) Synthesis of ullazines.
Figure 7: A) Reductive phosphorylation of aryl halides via conPET. B) Selected examples from the substrate sc...
Figure 8: A) Reductive dehalogenation of aryl halides via conPET and selected examples from the substrate sco...
Figure 9: A) Reductive C–H arylation of aryl halides via conPET (top) and selected examples from the substrat...
Figure 10: A) Reductive hydrodehalogenation of aryl halides with Mes-Acr-BF4. B) Selected examples from the su...
Figure 11: A) Reductive hydrodechlorination of aryl chlorides with 4-DPAIPN. B) Proposed formation of CO2•−. C...
Figure 12: A) Reductive conPET borylation with 3CzEPAIPN (top) and selected examples from the substrate scope ...
Figure 13: Scale-up of conPET phosphorylation with 3CzEPAIPN.
Figure 14: A) Borylation of 1d. B) Characteristics and structure of PC1 with green and red parts showing the l...
Figure 15: A) Reductive C–H arylation scope with polysulfide conPET (top) and selected examples from the subst...
Figure 16: Scale-up of A) C–H arylation and B) dehaloborylation with polysulfide photocatalysis in continuous-...
Figure 17: A) Formation of [Ir1]0 and [Ir2]0 upon PET between [Ir1]+ and Et3N. B) Mechanism of multi-photon ta...
Figure 18: A) Reductive hydrodehalogenation of aryl halides via multi-photon tandem photocatalysis. B) Selecte...
Figure 19: A) Carbonylative amidation of aryl halides in continuous flow. B) Selected examples from the substr...
Figure 20: A) General scheme for reductive (RQ) and oxidative quenching (OQ) protocols using [FeIII(btz)3](PF6)...
Figure 21: A) Carbonylative amidation of alkyl iodides with [IrIII(ppy)2(dtbbpy)]PF6. B) Selected examples fro...
Figure 22: A) Carboxylative C–N bond cleavage in cyclic amines. B) Selected examples from the substrate scope....
Figure 23: A) Formal reduction of alkenes to alkanes via transfer hydrogenation. B) Selected examples from the...
Figure 24: A) Birch-type reduction of benzenes with PMP-BPI. B) Selected examples from the substrate scope (sc...
Figure 25: Proposed mechanism of the OH− mediated conPET Birch-type reduction of benzene via generation of sol...
Figure 26: Reductive detosylation of N-tosylated amides with Mes-Acr-BF4. B) Selected examples from the substr...
Figure 27: A) Reductive detosylation of N-tosyl amides by dual PRC. B) Selected examples from the substrate sc...
Figure 28: A) Mechanism of the dual PRC based on PET between [Cu(dap)2]+ and DCA. B) Mechanism of the dual PRC...
Figure 29: A) N–O bond cleavage in Weinreb amides with anthracene. B) N–O bond cleavage in Weinreb amides rely...
Figure 30: A) Pentafluorosulfanylation and fluoride elimination. B) Mechanism of the pentafluorosulfanylation ...
Figure 31: A) α-Alkoxypentafluorosulfanylation (top) and selected examples from the substrate scope (bottom). ...
Figure 32: A) Oxidative amination of arenes with azoles catalyzed by N-Ph PTZ. B) Selected examples from the s...
Figure 33: A) C(sp3)–H bond activation by HAT via chloride oxidation by *N-Ph PTZ•+. B) Proposed mechanism for...
Figure 34: A) Recycling e-PRC C–H azolation of electron-rich arenes with pyrazoles using Mes-Acr+ as a photoca...
Figure 35: A) Radical ion e-PRC direct oxidation of unactivated arenes using TAC+ as an electro-activated phot...
Figure 36: A) Radical ion e-PRC direct oxidation of unactivated arenes using TPA as an electro-activated photo...
Figure 37: Proposed mechanism (top) and mode of preassembly (bottom).
Figure 38: A) Possible preassemblies of reactive (left) vs unreactive (right) arenes. B) Calculated spin densi...
Figure 39: A) Recycling e-PRC C(sp2 )–H acetoxylation of arenes using DDQ as a photocatalyst. B) Proposed cata...
Figure 40: Gram scale hydroxylation of benzene in a recirculated flow setup.
Figure 41: A) Radical ion e-PRC vicinal diamination of alkylarenes using TAC+ as an electro-activated photocat...
Figure 42: A) Sequential oxygenation of multiple adjacent C–H bonds under radical ion e-PRC using TAC+ as an e...
Figure 43: A) Enantioselective recycling e-PRC cyanation of benzylic C–H bonds using ADQS as photocatalyst. B)...
Figure 44: Proposed tandem mechanism by Xu and co-workers.
Figure 45: A) Enantioselective recycling e-PRC decarboxylative cyanation using Cu(acac)2, Ce(OTf)3 and a box l...
Figure 46: A) Enantioselective recycling e-PRC benzylic cyanation using Cu(MeCN)4BF4, box ligand and anthraqui...
Figure 47: A) Radical ion e-PRC acetoxyhydroxylation of aryl olefins using TAC+ as an electro-activated photoc...
Figure 48: Selected examples from the substrate scope.
Figure 49: Photoelectrochemical acetoxyhydroxylation in a recirculated flow setup.
Figure 50: A) Radical ion e-PRC aminooxygenation of aryl olefins using TAC+ as an electro-activated photocatal...
Figure 51: A) Recycling e-PRC C–H alkylation of heteroarenes with organic trifluoroborates using Mes-Acr+ as p...
Figure 52: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using CeCl3·7H2O as catalyst. B) ...
Figure 53: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using Fe(NH4)2(SO4)2·6H2O as cata...
Figure 54: A) Recycling e-PRC C–H alkylation of heteroarenes with alkyl oxalates and 4CzIPN as photocatalyst. ...
Figure 55: A) Recycling e-PRC decarboxylative C–H carbamoylation of heteroarenes using 4CzIPN as photocatalyst...
Figure 56: A) Photoelectrochemical HAT-mediated hydrocarbon activation via the chlorine radical. B) Proposed m...
Figure 57: A) Selected examples from the substrate scope. B) Gram and decagram scale semi-continuous flow PEC ...
Figure 58: A) Photoelectrochemical HAT-mediated dehydrogenative coupling of benzothiazoles with aliphatic C–H ...
Figure 59: A) Photoelectrochemical HAT activation of ethers using electro-activated TAC+ as photocatalyst. B) ...
Figure 60: Selected examples from the substrate scope.
Figure 61: A) Photoelectrochemical HAT-mediated synthesis of alkylated benzimidazo-fused isoquinolinones using...
Figure 62: A) Decoupled photoelectrochemical cerium-catalyzed oxydichlorination of alkynes using CeCl3 as cata...
Figure 63: Proposed decoupled photoelectrochemical mechanism.
Figure 64: A) Decoupled photoelectrochemical ring-opening bromination of tertiary cycloalkanols using MgBr2 as...
Figure 65: A) Recycling e-PRC ring-opening functionalization of cycloalkanols using CeCl3 as catalyst. B) Prop...
Figure 66: Selected examples from the substrate scope of the PEC ring-opening functionalization.
Figure 67: A) Radical ion e-PRC reduction of chloro- and bromoarenes using DCA as catalyst and various accepto...
Figure 68: A) Screening of different phthalimide derivatives as catalyst for the e-PRC reduction of aryl halid...
Figure 69: Screening of different organic catalysts for the e-PRC reduction of trialkylanilium salts.
Figure 70: A) e-PRC reduction of phosphonated phenols and anilinium salts. B) Selected examples from the subst...
Figure 71: A) ConPET and e-PRC reduction of 4-bromobenzonitrile using a naphthalene diimide (NDI) precatalyst ...
Figure 72: A) Radical ion e-PRC reduction of phosphinated aliphatic alcohols with n-BuO-NpMI as catalyst. B) C...
Figure 73: Selected examples from the substrate scope.
Figure 74: A) Recycling e-PRC reductive dimerization of benzylic chlorides using a [Cu2] catalyst. B) Proposed...
Figure 75: A) Decoupled photoelectrochemical C–H alkylation of heteroarenes through deamination of Katritzky s...
Figure 76: Proposed mechanism by Chen and co-workers.
Beilstein J. Org. Chem. 2023, 19, 1–26, doi:10.3762/bjoc.19.1
Graphical Abstract
Scheme 1: The power of radical retrosynthesis and the tactic of divergent total synthesis.
Figure 1: Evolution of radical chemistry for organic synthesis.
Scheme 2: Divergent total synthesis of α-pyrone-diterpenoids (Baran).
Scheme 3: Divergent synthesis of pyrone diterpenoids by merged chemoenzymatic and radical synthesis (part I, ...
Scheme 4: Divergent synthesis of pyrone diterpenoids by merged chemoenzymatic and radical synthesis (part II,...
Scheme 5: Divergent synthesis of drimane-type hydroquinone meroterpenoids (Li).
Scheme 6: Divergent synthesis of natural products isolated from Dysidea avara (Lu).
Scheme 7: Divergent synthesis of kaurene-type terpenoids (Lei).
Scheme 8: Divergent synthesis of 6-oxabicyclo[3.2.1]octane meroterpenoids (Lou).
Scheme 9: Divergent synthesis of crinipellins by radical-mediated Dowd–Backwith rearrangement (Xie and Ding).
Scheme 10: Divergent total synthesis of Galbulimima alkaloids (Shenvi).
Scheme 11: Divergent synthesis of eburnane alkaloids (Qin).
Scheme 12: Divergent synthesis of Aspidosperma alkaloids (Boger).
Scheme 13: Photoredox based synthesis of (−)-FR901483 (160) and (+)-TAN1251C (162, Gaunt).
Scheme 14: Divergent synthesis of bipolamines (Maimone).
Scheme 15: Flow chemistry divergency between aporphine and morphinandione alkaloids (Felpin).
Scheme 16: Divergent synthesis of pyrroloazocine natural products (Echavarren).
Scheme 17: Using TEMPO to stabilize radicals for the divergent synthesis of pyrroloindoline natural products (...
Scheme 18: Radical pathway for preparation of lignans (Zhu).
Scheme 19: Divergent synthesis of DBCOD lignans (Lumb).
Beilstein J. Org. Chem. 2022, 18, 1707–1719, doi:10.3762/bjoc.18.181
Graphical Abstract
Figure 1: General structure of grayanane natural products.
Scheme 1: Grayanane biosynthesis.
Scheme 2: Matsumoto’s relay approach.
Scheme 3: Shirahama’s total synthesis of (–)-grayanotoxin III.
Scheme 4: Newhouse’s syntheses of fragments 25 and 29.
Scheme 5: Newhouse’s total synthesis of principinol D.
Scheme 6: Ding’s total synthesis of rhodomolleins XX and XXII.
Scheme 7: First key step of Luo’s strategy.
Scheme 8: Luo’s total synthesis of grayanotoxin III.
Scheme 9: Synthesis of principinol E and rhodomollein XX.
Scheme 10: William’s synthetic effort towards pierisformaside C.
Scheme 11: Hong’s synthetic effort towards rhodojaponin III.
Scheme 12: Recent strategies for grayanane synthesis.
Beilstein J. Org. Chem. 2021, 17, 1440–1446, doi:10.3762/bjoc.17.99
Graphical Abstract
Figure 1: Structure of pavettamine 1 and its enantiomer 2.
Scheme 1: Established route for the synthesis of intermediate 4 [1].
Scheme 2: Alternative route. Reaction conditions: a) TrCl, pyridine, rt, overnight, 100%; b) DMAP, imidazole,...
Figure 2: Crystal structure of compound 9.
Scheme 3: Sequence showing the source of compound 9.
Scheme 4: Stereoselective reduction of intermediate 8 as key step towards intermediate 4. Reaction conditions...
Figure 3: Single crystal X-ray structure of compound 4.
Scheme 5: Synthesis of the C5 fragments from intermediate 4. Reaction conditions: a) i) TFAA, collidine, 0 °C...
Scheme 6: Synthesis of ent-pavettamine as the TFA salt 28. Reaction conditions: a) IBX, DMSO, rt, overnight, ...
Beilstein J. Org. Chem. 2019, 15, 2271–2276, doi:10.3762/bjoc.15.219
Graphical Abstract
Figure 1: Selected members of the acremine family [3-5].
Scheme 1: Retrosynthetic analysis of acremine F (5).
Scheme 2: Total synthesis of acremine F (5).
Scheme 3: Synthesis of acremines A and B through selective oxidation of acremine F.
Scheme 4: Proposed biomimetic dimerization of 5.
Scheme 5: Attempted intramolecular cyclization of 23.
Scheme 6: Attempted photochemical cyclization of 25.
Beilstein J. Org. Chem. 2019, 15, 1722–1757, doi:10.3762/bjoc.15.168
Graphical Abstract
Figure 1: Examples of three-carbon chirons.
Figure 2: Structures of derivatives of N-(1-phenylethyl)aziridine-2-carboxylic acid 5–8.
Figure 3: Synthetic equivalency of aziridine aldehydes 6.
Scheme 1: Synthesis of N-(1-phenylethyl)aziridine-2-carboxylates 5. Reagents and conditions: a) TEA, toluene,...
Scheme 2: Absolute configuration at C2 in (2S,1'S)-5a. Reagents and conditions: a) 20% HClO4, 80 °C, 30 h the...
Scheme 3: Major synthetic strategies for a 2-ketoaziridine scaffold [R* = (R)- or (S)-1-phenylethyl; R′ = Alk...
Scheme 4: Synthesis of cyanide (2S,1'S)-13. Reagents and conditions: a) NH3, EtOH/H2O, rt, 72 h; b) Ph3P, CCl4...
Scheme 5: Synthesis of key intermediates (R)-16 and (R)-17 for (R,R)-formoterol (14) and (R)-tamsulosin (15)....
Scheme 6: Synthesis of mitotic kinesin inhibitors (2R/S,1'R)-23. Reagents and conditions: a) H2, Pd(OH)2, EtO...
Scheme 7: Synthesis of (R)-mexiletine ((R)-24). Reagents and conditions: a) TsCl, TEA, DMAP, CH2Cl2, rt, 1 h;...
Scheme 8: Synthesis of (−)-cathinone ((S)-27). Reagents and conditions: a) PhMgBr, ether, 0 °C; b) H2, 10% Pd...
Scheme 9: Synthesis of N-Boc-norpseudoephedrine ((1S,2S)-(+)-29) and N-Boc-norephedrine ((1R,2S)-29). Reagent...
Scheme 10: Synthesis of (−)-ephedrine ((1R,2S)-31). Reagents and conditions: a) TfOMe, MeCN then NaBH3CN, rt; ...
Scheme 11: Synthesis of xestoaminol C ((2S,3R)-35), 3-epi-xestoaminol C ((2S,3S)-35) and N-Boc-spisulosine ((2S...
Scheme 12: Synthesis of ʟ-tryptophanol ((S)-41). Reagents and conditions: a) CDI, MeCN, rt, 1 h then TMSI, MeC...
Scheme 13: Synthesis of ʟ-homophenylalaninol ((S)-42). Reagents and conditions: a) NaH, THF, 0 °C to −78 °C, 1...
Scheme 14: Synthesis of ᴅ-homo(4-octylphenyl)alaninol ((R)-47) and a sphingolipid analogue (R)-48. Reagents an...
Scheme 15: Synthesis of florfenicol ((1R,2S)-49). Reagents and conditions: a) (S)-1-phenylethylamine, TEA, MeO...
Scheme 16: Synthesis of natural tyroscherin ((2S,3R,6E,8R,10R)-55). Reagents and conditions: a) I(CH2)3OTIPS, t...
Scheme 17: Syntheses of (−)-hygrine (S)-61, (−)-hygroline (2S,2'S)-62 and (−)-pseudohygroline (2S,2'R)-62. Rea...
Scheme 18: Synthesis of pyrrolidine (3S,3'R)-68, a fragment of the fluoroquinolone antibiotic PF-00951966. Rea...
Scheme 19: Synthesis of sphingolipid analogues (R)-76. Reagents and conditions: a) BnBr, Mg, THF, reflux, 6 h;...
Scheme 20: Synthesis of ᴅ-threo-PDMP (1R,2R)-81. Reagents and conditions: a) TMSCl, NaI, MeCN, rt, 1 h 50 min,...
Scheme 21: Synthesis of the sphingolipid analogue SG-14 (2S,3S)-84. Reagents and conditions: a) LiAlH4, THF, 0...
Scheme 22: Synthesis of the sphingolipid analogue SG-12 (2S,3R)-88. Reagents and conditions: a) 1-(bromomethyl...
Scheme 23: Synthesis of sphingosine-1-phosphate analogues DS-SG-44 and DS-SG-45 (2S,3R)-89a and (2S,3R)-89a. R...
Scheme 24: Synthesis of N-Boc-safingol ((2S,3S)-95) and N-Boc-ᴅ-erythro-sphinganine ((2S,3R)-95). Reagents and...
Scheme 25: Synthesis of ceramide analogues (2S,3R)-96. Reagents and conditions: a) NaBH4, ZnCl2, MeOH, −78 °C,...
Scheme 26: Synthesis of orthogonally protected serinols, (S)-101 and (R)-102. Reagents and conditions: a) BnBr...
Scheme 27: Synthesis of N-acetyl-3-phenylserinol ((1R,2R)-105). Reagents and conditions: a) AcOH, CH2Cl2, refl...
Scheme 28: Synthesis of (S)-linezolid (S)-107. Reagents and conditions: a) LiAlH4, THF, 0 °C to reflux; b) Boc2...
Scheme 29: Synthesis of (2S,3S,4R)-2-aminooctadecane-1,3,4-triol (ᴅ-ribo-phytosphingosine) (2S,3S,4R)-110. Rea...
Scheme 30: Syntheses of ᴅ-phenylalanine (R)-116. Reagents and conditions: a) AcOH, CH2Cl2, reflux, 4 h; b) MsC...
Scheme 31: Synthesis of N-Boc-ᴅ-3,3-diphenylalanine ((R)-122). Reagents and conditions: a) PhMgBr, THF, −78 °C...
Scheme 32: Synthesis of ethyl N,N’-di-Boc-ʟ-2,3-diaminopropanoate ((S)-125). Reagents and conditions: a) NaN3,...
Scheme 33: Synthesis of the bicyclic amino acid (S)-(+)-127. Reagents and conditions: a) BF3·OEt2, THF, 60 °C,...
Scheme 34: Synthesis of lacosamide, (R)-2-acetamido-N-benzyl-3-methoxypropanamide (R)-130. Reagents and condit...
Scheme 35: Synthesis of N-Boc-norfuranomycin ((2S,2'R)-133). Reagents and conditions: a) H2C=CHCH2I, NaH, THF,...
Scheme 36: Synthesis of MeBmt (2S,3R,4R,6E)-139. Reagents and conditions: a) diisopropyl (S,S)-tartrate (E)-cr...
Scheme 37: Synthesis of (+)-polyoxamic acid (2S,3S,4S)-144. Reagents and conditions: a) AD-mix-α, MeSO2NH2, t-...
Scheme 38: Synthesis of the protected 3-hydroxy-ʟ-glutamic acid (2S,3R)-148. Reagents and conditions: a) LiHMD...
Scheme 39: Synthesis of (+)-isoserine (R)-152. Reagents and conditions: a) AcCl, MeCN, rt, 0.5 h then Na2CO3, ...
Scheme 40: Synthesis of (3R,4S)-N3-Boc-3,4-diaminopentanoic acid (3R,4S)-155. Reagents and conditions: a) Ph3P...
Scheme 41: Synthesis of methyl (2S,3S,4S)-4-(dimethylamino)-2,3-dihydroxy-5-methoxypentanoate (2S,3S,4S)-159. ...
Scheme 42: Syntheses of methyl (3S,4S) 4,5-di-N-Boc-amino-3-hydroxypentanoate ((3S,4S)-164), methyl (3S,4S)-4-N...
Scheme 43: Syntheses of (3R,5S)-5-(aminomethyl)-3-(4-methoxyphenyl)dihydrofuran-2(3H)-one ((3R,5S)-168). Reage...
Scheme 44: Syntheses of a series of imidazolin-2-one dipeptides 175–177 (for R' and R'' see text). Reagents an...
Scheme 45: Syntheses of (2S,3S)-N-Boc-3-hydroxy-2-hydroxymethylpyrrolidine ((2S,3S)-179). Reagents and conditi...
Scheme 46: Syntheses of enantiomers of 1,4-dideoxy-1,4-imino-ʟ- and -ᴅ-lyxitols (2S,3R,4S)-182 and (2R,3S,4R)-...
Scheme 47: Synthesis of 1,4-dideoxy-1,4-imino-ʟ-ribitol (2S,3S,4R)-182. Reagents and conditions: a) AcOH, CH2Cl...
Scheme 48: Syntheses of 1,4-dideoxy-1,4-imino-ᴅ-arabinitol (2R,3R,4R)-182 and 1,4-dideoxy-1,4-imino-ᴅ-xylitol ...
Scheme 49: Syntheses of natural 2,5-imino-2,5,6-trideoxy-ʟ-gulo-heptitol ((2S,3R,4R,5R)-184) and its C4 epimer...
Scheme 50: Syntheses of (−)-dihydropinidine ((2S,6R)-187a) (R = C3H7) and (2S,6R)-isosolenopsins (2S,6R)-187b ...
Scheme 51: Syntheses of (+)-deoxocassine ((2S,3S,6R)-190a, R = C12H25) and (+)-spectaline ((2S,3S,6R)-190b, R ...
Scheme 52: Synthesis of (−)-microgrewiapine A ((2S,3R,6S)-194a) and (+)-microcosamine A ((2S,3R,6S)-194b). Rea...
Scheme 53: Syntheses of ʟ-1-deoxynojirimycin ((2S,3S,4S,5R)-200), ʟ-1-deoxymannojirimycin ((2S,3S,4S,5S)-200) ...
Scheme 54: Syntheses of 1-deoxy-ᴅ-galacto-homonojirimycin (2R,3S,4R,5S)-211. Reagents and conditions: a) MeONH...
Scheme 55: Syntheses of 7a-epi-hyacinthacine A1 (1S,2R,3R,7aS)-220. Reagents and conditions: a) TfOTBDMS, 2,6-...
Scheme 56: Syntheses of 8-deoxyhyacinthacine A1 ((1S,2R,3R,7aR)-221). Reagents and conditions: a) H2, Pd/C, PT...
Scheme 57: Syntheses of (+)-lentiginosine ((1S,2S,8aS)-227). Reagents and conditions: a) (EtO)2P(O)CH2COOEt, L...
Scheme 58: Syntheses of 8-epi-swainsonine (1S,2R,8S,8aR)-231. Reagents and conditions: a) Ph3P=CHCOOMe, MeOH, ...
Scheme 59: Synthesis of a protected vinylpiperidine (2S,3R)-237, a key intermediate in the synthesis of (−)-sw...
Scheme 60: Synthesis of a modified carbapenem 245. Reagents and conditions: a) AcOEt, LiHMDS, THF, −78 °C, 1.5...
Beilstein J. Org. Chem. 2018, 14, 416–429, doi:10.3762/bjoc.14.30
Graphical Abstract
Scheme 1: The first ENGase-catalysed glycosylation of a GlcNAc acceptor using an N-glycan oxazoline as donor.
Scheme 2: Production of N-glycan oxazolines from peracetylated sugars using Lewis acids.
Scheme 3: Direct conversion of unprotected GlcNAc to a glycosyl oxazoline by treatment with DMC and Et3N in w...
Scheme 4: Total synthesis of a truncated complex biantennary N-glycan oxazoline via an epimerisation approach...
Scheme 5: Wangs’s total synthesis of an N-glycan oxazoline incorporating click handles, employing Crich direc...
Scheme 6: Wangs’s total synthesis of an N-glycan dodecasaccharide oxazoline employing final step oxazoline fo...
Scheme 7: Production of a phosphorylated N-glycan oxazoline, employing final step oxazoline formation with DM...
Scheme 8: Enzymatic degradation of locust bean gum, and chemical conversion into an N-glycan dodecasaccharide...
Scheme 9: Production of a complex biantennary N-glycan oxazoline from hens’ eggs by semi-synthesis via isolat...
Scheme 10: Production of a high mannose (Man-9) N-glycan oxazoline from soy bean flour.
Scheme 11: Production of a triantennary N-glycan oxazoline from bovine feruin by semi-synthesis.
Beilstein J. Org. Chem. 2017, 13, 1239–1279, doi:10.3762/bjoc.13.123
Graphical Abstract
Scheme 1: Solution-state conformations of D-glucose.
Scheme 2: Enzymatic synthesis of oligosaccharides.
Scheme 3: Enzymatic synthesis of a phosphorylated glycoprotein containing a mannose-6-phosphate (M6P)-termina...
Scheme 4: A) Selected GTs-mediated syntheses of oligosaccharides and other biologically active glycosides. B)...
Scheme 5: Enzymatic synthesis of nucleosides.
Scheme 6: Fischer glycosylation strategies.
Scheme 7: The basis of remote activation (adapted from [37]).
Scheme 8: Classic remote activation employing a MOP donor to access α-anomeric alcohols, carboxylates, and ph...
Figure 1: Synthesis of monoprotected glycosides from a (3-bromo-2-pyridyloxy) β-D-glycopyranosyl donor under ...
Scheme 9: Plausible mechanism for the synthesis of α-galactosides. TBDPS = tert-butyldiphenylsilyl.
Scheme 10: Synthesis of the 6-O-monoprotected galactopyranoside donor for remote activation.
Scheme 11: UDP-galactopyranose mutase-catalyzed isomerization of UDP-Galp to UDP-Galf.
Scheme 12: Synthesis of the 1-thioimidoyl galactofuranosyl donor.
Scheme 13: Glycosylation of MeOH using a self-activating donor in the absence of an external activator. a) Syn...
Scheme 14: The classical Lewis acid-catalyzed glycosylation.
Figure 2: Unprotected glycosyl donors used for the Lewis acid-catalyzed protecting group-free glycosylation r...
Scheme 15: Four-step synthesis of the phenyl β-galactothiopyranosyl donor.
Scheme 16: Protecting-group-free C3′-regioselective glycosylation of sucrose with α–F Glc.
Scheme 17: Synthesis of the α-fluoroglucosyl donor.
Figure 3: Protecting-group-free glycosyl donors and acceptors used in the Au(III)-catalyzed glycosylation.
Scheme 18: Synthesis of the mannosyl donor used in the study [62].
Scheme 19: The Pd-catalyzed stereoretentive glycosylation of arenes using anomeric stannane donors.
Scheme 20: Preparation of the protecting-group-free α and β-stannanes from advanced intermediates for stereoch...
Figure 4: Selective anomeric activating agents providing donors for direct activation of the anomeric carbon.
Scheme 21: One-step access to sugar oxazolines or 1,6-anhydrosugars.
Scheme 22: Enzymatic synthesis of a chitoheptaose using a mutant chitinase.
Scheme 23: One-pot access to glycosyl azides [73], dithiocarbamates [74], and aryl thiols using DMC activation and sub...
Scheme 24: Plausible reaction mechanism.
Scheme 25: Protecting-group-free synthesis of anomeric thiols from unprotected 2-deoxy-2-N-acetyl sugars.
Scheme 26: Protein conjugation of TTL221-PentK with a hyaluronan hexasaccharide thiol.
Scheme 27: Proposed mechanism.
Scheme 28: Direct two-step one-pot access to glycoconjugates through the in situ formation of the glycosyl azi...
Scheme 29: DMC as a phosphate-activating moiety for the synthesis of diphosphates. aβ-1,4-galactose transferas...
Figure 5: Triazinylmorpholinium salts as selective anomeric activating agents.
Scheme 30: One-step synthesis of DBT glycosides from unprotected sugars in aqueous medium.
Scheme 31: Postulated mechanism for the stereoselective formation of α-glycosides.
Scheme 32: DMT-donor synthesis used for metal-catalyzed glycosylation of simple alcohols.
Figure 6: Protecting group-free synthesis of glycosyl sulfonohydrazides (GSH).
Figure 7: The use of GSHs to access 1-O-phosphoryl and alkyl glycosides. A) Glycosylation of aliphatic alcoho...
Scheme 33: A) Proposed mechanism of glycosylation. B) Proposed mechanism for stereoselective azidation of the ...
Scheme 34: Mounting GlcNAc onto a sepharose solid support through a GSH donor.
Scheme 35: Lawesson’s reagent for the formation of 1,2-trans glycosides.
Scheme 36: Protecting-group-free protein conjugation via an in situ-formed thiol glycoside [98].
Scheme 37: pH-Specific glycosylation to functionalize SAMs on gold.
Figure 8: Protecting-group-free availability of phenolic glycosides under Mitsunobu conditions. DEAD = diethy...
Scheme 38: Accessing hydroxyazobenzenes under Mitsunobu conditions for the study of photoswitchable labels. DE...
Scheme 39: Stereoselective protecting-group-free glycosylation of D-glucose to provide the β-glucosyl benzoic ...
Figure 9: Direct synthesis of pyranosyl nucleosides from unactivated and unprotected ribose using optimized M...
Figure 10: Direct synthesis of furanosyl nucleosides from 5-O-monoprotected ribose in a one-pot glycosylation–...
Figure 11: Synthesis of ribofuranosides using a monoprotected ribosyl donor via an anhydrose intermediate.
Figure 12: C5′-modified nucleosides available under our conditions.
Scheme 40: Plausible reaction mechanism for the formation of the anhydrose.
Figure 13: Direct glycosylation of several aliphatic alcohols using catalytic Ti(Ot-Bu)4 in the presence of D-...
Figure 14: Access to glycosides using catalytic PPh3 and CBr4.
Figure 15: Access to ribofuranosyl glycosides as the major product under catalytic conditions. aLiOCl4 (2.0 eq...
Beilstein J. Org. Chem. 2017, 13, 728–733, doi:10.3762/bjoc.13.72
Graphical Abstract
Figure 1: The derivatives of all-cis-2,3,5,6-tetrafluorocyclohexane.
Scheme 1: Reagents and conditions: a) Li (2.5 equiv), NH3, t-BuOH (1 equiv), MeI (2 equiv), 3 h, −78 °C, 18 h...
Scheme 2: Reagents and conditions: a) Et3N·3HF (8 equiv), 18 h, 140 °C; b) Tf2O (4 equiv), pyridine, 1 h, 0 °...
Scheme 3: Reagents and conditions: a) Et3N·3HF (8 equiv), 18 h, 140 °C; b) Tf2O (4 equiv), pyridine, 1 h, 0 °...
Scheme 4: Reagents and conditions: a) terephthaloyl chloride (1 equiv), Et3N (4 equiv), DMAP (20 mol %), DCM,...
Figure 2: X-ray structures and crystal packing of compounds 13, 14 and 15.
Beilstein J. Org. Chem. 2017, 13, 267–284, doi:10.3762/bjoc.13.30
Graphical Abstract
Scheme 1: Mechanism for the reduction under metal dissolving conditions.
Scheme 2: Example of decyanation in metal dissolving conditions coupled with deprotection [30]. TBDMS = tert-buty...
Scheme 3: Preparation of α,ω-dienes [18,33].
Scheme 4: Cyclization reaction using a radical probe [18].
Scheme 5: Synthesis of (±)-xanthorrhizol (8) [39].
Scheme 6: Mechanism for the reduction of α-aminonitriles by hydride donors.
Scheme 7: Synthesis of phenanthroindolizidines and phenanthroquinolizidines [71].
Scheme 8: Two-step synthesis of 5-unsubstituted pyrrolidines (25 examples and 1 synthetic application, see be...
Scheme 9: Synthesis of (±)-isoretronecanol 19. DBU = 1,8-diazabicyclo[5.4.0]undec-7-ene [74].
Scheme 10: Proposed mechanism with 14a for the NaBH4 induced decyanation reaction (“BH3” = BH3·THF) [74].
Scheme 11: Reductive decyanation by a sodium hydride–iodide composite (26 examples) [81].
Scheme 12: Proposed mechanism for the reduction by NaH [81].
Scheme 13: Reductive decyanation catalyzed by nickel nanoparticles. Yields are given in weight % from GC–MS da...
Scheme 14: Decyanation of 2-cyanobenzo[b]thiophene [87].
Scheme 15: Simplified pathways involved in transition-metal-promoted reductive decyanations [93,95].
Scheme 16: Fe-catalyzed reductive decyanation. Numbers in square brackets represent turnover numbers. The TONs...
Scheme 17: Rh-catalyzed reductive decyanation of aryl nitriles (18 examples, 2 synthetic applications) [103].
Scheme 18: Rh-catalyzed reductive decyanation of aliphatic nitriles (15 examples, one synthetic application) [103].
Scheme 19: Ni-catalyzed reductive decyanation (method A: 28 examples and 2 synthetic applications; method B: 3...
Scheme 20: Reductive decyanation catalyzed by the nickel complex 58 (method A, 14 examples, yield ≥ 20% and 1 ...
Scheme 21: Proposed catalytic cycle for the nickel complex 58 catalyzed decyanation (method A). Only the cycle...
Scheme 22: Synthesis of bicyclic lactones [119,120].
Scheme 23: Reductive decyanation of malononitriles and cyanoacetates using NHC-boryl radicals (9 examples). Fo...
Scheme 24: Proposed mechanism for the reduction by NHC-boryl radicals. The other possible pathway (addition of ...
Scheme 25: Structures of organic electron-donors. Only the major Z isomer of 80 is shown [125,127].
Scheme 26: Reductive decyanation of malononitriles and cyanoacetates using organic electron-donors (method A, ...
Scheme 27: Photoreaction of dibenzylmalononitrile with 81 [128].
Scheme 28: Examples of decyanation promoted in acid or basic media [129,131,134,135].
Scheme 29: Mechanism proposed for the base-induced reductive decyanation of diphenylacetonitriles [136].
Scheme 30: Reductive decyanation of triarylacetonitriles [140].
Beilstein J. Org. Chem. 2016, 12, 2828–2833, doi:10.3762/bjoc.12.282
Graphical Abstract
Figure 1: Alkylseleno glycosides, such as 1, are used as tools for X-ray crystallography of lectins. Some lec...
Scheme 1: Synthesis of 3 through initial introduction of the seleno aglycon and subsequent O-methylation. Rea...
Scheme 2: Synthesis of compound 3 via initial selective 2-O-methylation followed by the introduction of the s...
Beilstein J. Org. Chem. 2014, 10, 163–193, doi:10.3762/bjoc.10.14
Graphical Abstract
Scheme 1: Vogel’s first approach towards the divinylcyclopropane rearrangement [4] and characterization of cis-d...
Scheme 2: Transition states for the Cope rearrangement and the related DVCPR. Ts = transition state.
Scheme 3: Two possible mechanisms of trans-cis isomerizations of divinylcyclopropanes.
Scheme 4: Proposed biosynthesic pathway to ectocarpene (21), an inactive degradation product of a sexual pher...
Scheme 5: Proposed biosynthesis of occidenol (25) and related natural compounds.
Scheme 6: Gaich’s bioinspired system using the DVCPR to mimick the dimethylallyltryptophan synthase. DMAPP = ...
Scheme 7: Iguchi’s total synthesis of clavubicyclone, part 1.
Scheme 8: Iguchi’s total synthesis of clavubicyclone, part 2.
Scheme 9: Wender’s syntheses of the two pseudoguainanes confertin (50) and damsinic acid (51) and Pier’s appr...
Scheme 10: Overman’s total synthesis of scopadulcic acid B.
Scheme 11: Davies’ total syntheses of tremulenolide A and tremulenediol A.
Scheme 12: Davies formal [4 + 3] cycloaddition approach towards the formal synthesis of frondosin B.
Scheme 13: Davies and Sarpongs formal [4 + 3]-cycloaddition approach towards barekoxide (106) and barekol (107...
Scheme 14: Davies formal [4 + 3]-cycloaddition approach to 5-epi-vibsanin E (115) containing an intermediate c...
Scheme 15: Echavarren’s total synthesis of schisanwilsonene A (126) featuring an impressive gold-catalzed casc...
Scheme 16: Davies early example of a formal [4 + 3]-cycloaddition in alkaloids synthesis.
Scheme 17: Fukuyama’s total synthesis of gelsemine, part 1.
Scheme 18: Fukuyama’s total synthesis of gelsemine, featuring a divinylcyclopropane rearrangement, part 2.
Scheme 19: Kende’s total synthesis of isostemofoline, using a formal [4 + 3]-cycloaddition, including an inter...
Scheme 20: Danishefsky’s total synthesis of gelsemine, part 1.
Scheme 21: Danishefsky’s total synthesis of gelsemine, part 2.
Scheme 22: Fukuyama’s total synthesis of gelsemoxonine.
Scheme 23: Wender’s synthetic access to the core skeleton of tiglianes, daphnanes and ingenanes.
Scheme 24: Davies’ approach towards the core skeleton of CP-263,114 (212).
Scheme 25: Wood’s approach towards actinophyllic acid.
Scheme 26: Takeda’s approach towards the skeleton of the cyanthins, utilitizing the divinylcyclopropane rearra...
Scheme 27: Donaldson’s organoiron route towards the guianolide skeleton.
Scheme 28: Stoltz’s tandem Wolff/DVCPR rearrangement.
Scheme 29: Stephenson’s tandem photocatalysis/arylvinylcyclopropane rearrangement.
Scheme 30: Padwa’s rhodium cascade involving a DVCPR.
Scheme 31: Matsubara’s version of a DVCPR.
Scheme 32: Toste’s tandem gold-catalyzed Claisen-rearrangement/DVCPR.
Scheme 33: Ruthenium- and gold-catalyzed versions of tandem reactions involving a DVCPR.
Scheme 34: Tungsten, platinum and gold catalysed cycloisomerizations leading to a DVCPR.
Scheme 35: Reisman’s total synthesis of salvileucalin B, featuring an (undesired) vinylcyclopropyl carbaldehyd...
Scheme 36: Studies on the divinylepoxide rearrangement.
Scheme 37: Studies on the vinylcyclopropanecarbonyl rearrangement.
Scheme 38: Nitrogen-substituted variants of the divinylcyclopropane rearrangement.
Beilstein J. Org. Chem. 2013, 9, 1931–1935, doi:10.3762/bjoc.9.228
Graphical Abstract
Figure 1: Structure of symbiodinolide (1).
Scheme 1: Our previous synthesis of the C79–C96 fragment 7.
Scheme 2: Retrosynthetic analysis of the C79–C97 fragment 8.
Scheme 3: Synthesis of aldehyde 20.
Scheme 4: Synthesis of PT-sulfones 23 and 24.
Scheme 5: Synthesis of the C79–C97 fragment 27.
Beilstein J. Org. Chem. 2013, 9, 557–576, doi:10.3762/bjoc.9.61
Graphical Abstract
Scheme 1: Key radical step in the total synthesis of (–)-dendrobine.
Scheme 2: Radical cascade in the total synthesis of (±)-13-deoxyserratine (ACCN = 1,1'-azobis(cyclohexanecarb...
Scheme 3: Formation of the complete skeleton of (±)-fortucine.
Scheme 4: Model radical sequence for the synthesis of quadrone.
Scheme 5: Radical cascade using the Barton decarboxylation.
Scheme 6: Simplified mechanism for the xanthate addition to alkenes.
Scheme 7: Synthesis of β-lactam derivatives.
Scheme 8: Sequential additions to three different alkenes (PhthN = phthalimido).
Scheme 9: Key cascade in the total synthesis of (±)-matrine (43).
Scheme 10: Synthesis of complex tetralones.
Scheme 11: Synthesis of functionalised azaindoline and indole derivatives.
Scheme 12: Synthesis of thiochromanones.
Scheme 13: Synthesis of complex benzothiepinones. Conditions: 1) CF3COOH; 2) RCHO / AcOH (PMB = p-methoxybenzy...
Scheme 14: Formation and capture of a cyclic nitrone.
Scheme 15: Synthesis of bicyclic cyclobutane motifs.
Scheme 16: Construction of the CD rings of steroids.
Scheme 17: Rapid assembly of polyquinanes.
Scheme 18: Formation of a polycyclic structure via an allene intermediate.
Scheme 19: A polycyclic structure via the alkylative Birch reduction.
Scheme 20: Synthesis of polycyclic pyrimidines and indoline structures.
Scheme 21: Construction of a trans-decalin derivative.
Scheme 22: Multiple uses of a chloroacetonyl xanthate.
Scheme 23: A convergent route to spiroketals.
Scheme 24: A modular approach to 3-arylpiperidines.
Scheme 25: A convergent route to cyclopentanols and to functional allenes.
Scheme 26: Allylation and vinylation of a xanthate and an iodide.
Scheme 27: Vinyl epoxides as allylating agents.
Scheme 28: Radical allylations using allylic alcohol derivatives.
Scheme 29: Synthesis of variously substituted lactams.
Scheme 30: Nickel-mediated synthesis of unsaturated lactams.
Scheme 31: Total synthesis of (±)-3-demethoxy-erythratidinone.
Scheme 32: Generation and capture of an iminyl radical from an oxime ester.
Beilstein J. Org. Chem. 2012, 8, 1134–1143, doi:10.3762/bjoc.8.126
Graphical Abstract
Figure 1: Structure of Lex and analogues 2–5.
Figure 2: Monosaccharide building blocks 6–13.
Scheme 1: Synthesis of trichloroacetimidate donors 9–11.
Scheme 2: Synthesis of trisaccharides 26–28 and deprotection reactions giving 3–5.
Beilstein J. Org. Chem. 2011, 7, 1115–1123, doi:10.3762/bjoc.7.128
Graphical Abstract
Scheme 1: The concept of using allylic reactivity enhancement to facilitate diglycoside synthesis.
Scheme 2: (i) Phosphomolybdic acid, EtOH, MeCN, 0 °C→RT, 63%; (ii) a) NaOMe, MeOH, 87%; b) TBDMSCl, imidazole...
Scheme 3: (i) DIAD, PPh3, THF, 0 °C→RT; 10, 91%; 11, 88%; 12, 76%; 13, 91%; 14, 91%; 15, 71%.
Scheme 4: (i) K2OsO4, NMO, acetone, H2O; 16, 88%; 17, 73%; (ii) Ac2O, py, 83%; (iii) MeOH, HCl (1 M aq.); 19,...
Scheme 5: (i) Cl3CCN, DBU, CH2Cl2, 99%; (ii) TMPP, Pd(dba)2, 5, Et3N, MeCN, 24, 44%; 25, 15%; 26, 5%; 27, 6%.
Figure 1: Previously synthesised amine-linked diglycosides.
Beilstein J. Org. Chem. 2010, 6, No. 17, doi:10.3762/bjoc.6.17
Graphical Abstract
Figure 1: Structure of Lex analogues 1–3.
Figure 2: Monosaccharide glycosyl acceptors (4–6) and donors (7–9) used in this study.
Scheme 1: Synthesis of monosaccharide glycosyl acceptors 4–6.
Scheme 2: Synthesis of the galactosyl donor 8.
Scheme 3: Convergent synthesis of trisaccharides 29–32.
Scheme 4: Proposed mechanism for the desulfurization of thioacetate 31 under dissolving metal conditions.
Beilstein J. Org. Chem. 2009, 5, No. 33, doi:10.3762/bjoc.5.33
Graphical Abstract
Scheme 1: Aziridine containing natural products.
Scheme 2: Mitomycin structures and nomenclature.
Scheme 3: Base catalysed epimerization of mitomycin B.
Scheme 4: Biosynthesis of mitomycin C (MMC) 7.
Scheme 5: Mode of action of mitomycin C.
Scheme 6: The N–C3–C9a disconnection.
Scheme 7: Danishefsky’s Retrosynthesis of mitomycin K.
Scheme 8: Hetero Diels–Alder reaction en route to mitomycins.
Scheme 9: Nitroso Diels–Alder cycloaddition.
Scheme 10: Frank azide cycloadddition.
Scheme 11: Final steps of mitomycin K synthesis. aPDC, DCM; bPhSCH2N3, PhH, 80 °C; cL-selectride, THF, −78 °C; ...
Scheme 12: Naruta–Maruyama retrosynthesis.
Scheme 13: Synthesis of a leucoaziridinomitosane by nitrene cycloaddition. aAlCl3-Et2O; bNaH, ClCH2OMe; cn-BuL...
Scheme 14: Thermal decomposition of azidoquinone 51.
Scheme 15: Diastereoselectivity during the cycloaddition.
Scheme 16: Oxidation with iodo-azide.
Scheme 17: Williams’ approach towards mitomycins.aDEIPSCl, Imidazole, DCM; bPd/C, HCO2NH4, MeOH; cAllocCl, NaH...
Scheme 18: Synthesis of pyrrolidones by homoconjugate addition.
Scheme 19: Homoconjugate addition on the fully functionalized substrate.
Scheme 20: Introduction of the olefin.
Scheme 21: Retrosynthesis of N–C9a, N–C3 bond formation.
Scheme 22: Synthesis of the pyrrolo[1,2]indole 82 using N-PSP activation.aAc2O, Py; bAc2O, Hg(OAc)2, AcOH, 90%...
Scheme 23: Synthesis of an aziridinomitosane. am-CPBA, DCM then iPr2NH, CCl4 reflux; bK2CO3, MeOH; cBnBr, KH; d...
Scheme 24: Oxidation products of a leucoaziridinomitosane obtained from a Polonovski oxidation.
Scheme 25: Polonovski oxidation of an aziridinomitosane. am-CPBA; bPd/C, H2; cDimethoxypropane, PPTS.
Scheme 26: The C1–C9a disconnection.
Scheme 27: Ziegler synthesis of desmethoxymitomycin A.aIm2C=O, THF; bNH3; cTMSOTf, 2,6-di-tert-butylpyridine, ...
Scheme 28: Transformation of sodium erythorbate.aTBDMSCl; bNaN3; cPPh3; d(Boc)2O, DMAP; eTBAF; fTf2O, Pyr.
Scheme 29: Formation of C9,C10-unsaturation in the mitomycins. am-CPBA, DCM; bO3, MeOH; cMe2S; dKHMDS, (EtO)3P...
Scheme 30: Fragmentation mechanism.
Scheme 31: Michael addition-cyclisation.
Scheme 32: SmI2 8-endo-dig cyclisation.
Scheme 33: Synthesis of pyrrolo[1,2-a]indole by 5-exo-dig radical cyclization.
Scheme 34: The C9–C9a disconnection.
Scheme 35: Intramolecular nitrile oxide cycloaddition.
Scheme 36: Regioselectivity of the INOC.
Scheme 37: Fukuyama’s INOC strategy.
Scheme 38: Synthesis of a mitosane core by rearrangement of a 1-(1-pyrrolidinyl)-1,3-butadiene.
Scheme 39: Sulikowski synthesis of an aziridinomitosene. aPd(Tol3P)2Cl2, Bu3SnF, 140; bH2, Pd/C; cTFAA, Et3N; d...
Scheme 40: Enantioselective carbene insertion.
Scheme 41: Parson’s radical cyclization.
Scheme 42: Cha’s mitomycin B core synthesis.
Scheme 43: The N-aromatic disconnection.
Scheme 44: Kishi retrosynthesis.
Scheme 45: Kishi synthesis of a starting material. aallyl bromide, K2CO3, acetone, reflux; bN,N-Dimethylanilin...
Scheme 46: Kishi synthesis of MMC 7. aLDA, THF, −78 °C then PhSeBr, THF, −78 °C; bH2O2, THF-EtOAc; cDIBAL, DCM...
Scheme 47: Acid catalyzed degradation of MMC 7.
Scheme 48: In vivo formation of apomitomycin B.
Scheme 49: Advanced intermediate for apomitomycin B synthesis.
Scheme 50: Remers synthesis of a functionalized mitosene. aTMSCl, Et3N, ZnCl2 then NBS; bAcOK; cNH2OH; dPd/C, H...
Scheme 51: Coleman synthesis of desmethoxymitomycin A. aSnCl2, PhSH, Et3N, CH3CN; bClCO2Bn, Et3N; cPPh3, DIAD,...
Scheme 52: Transition state and pyrrolidine synthesis.
Scheme 53: Air oxidation of mitosanes and aziridinomitosanes.
Scheme 54: The C9-aromatic disconnection.
Scheme 55: Synthesis of the aziridine precursor. aLHMDS, THF; bNaOH; c(s)-α-Me-BnNH2, DCC, HOBT; dDIBAL; eK2CO3...
Scheme 56: Synthesis of 206 via enamine conjugate addition.
Scheme 57: Rapoport synthesis of an aziridinomitosene.
Scheme 58: One pot synthesis of a mitomycin analog.
Scheme 59: Synthesis of compound 218 via intramolecular Heck coupling. aEtMgCl, THF, then 220; bMsCl, Et3N; cN...
Scheme 60: Elaboration of indole 223. aEt3N, Ac2O; bAcOH; cSOCl2, Et3N; dNaN3, DMF; eH2SO4, THF; fK2CO3, MeOH; ...
Scheme 61: C9-C9a functionalization from indole.
Scheme 62: Synthesis of mitomycin K. a2 equiv. MoO5.HMPA, MeOH; bPPh3, Et3N, THF-H2O; cMeOTf, Py, DCM; dMe3SiCH...
Scheme 63: Configurational stability of mitomycin K derivatives.
Scheme 64: Epimerization of carbon C9a in compound 227b.
Scheme 65: Corey–Chaykovsky synthesis of indol 235.
Scheme 66: Cory intramolecular aza-Darzens reaction for the formation of aziridinomitosene 239.
Scheme 67: Jimenez synthesis of aziridinomitosene 242.
Scheme 68: Von Braun opening of indoline 244.
Scheme 69: C9a oxidation of an aziridinomitosane with DDQ/OsO4.
Scheme 70: Synthesis of epi-mitomycin K. aNaH, Me2SO4; bH2, Pd/C; cMitscher reagent [165]; d[(trimethylsilyl)methyl...
Scheme 71: Mitomycins rearrangement.
Scheme 72: Fukuyama’s retrosynthesis.
Scheme 73: [2+3] Cycloaddition en route to isomitomycin A. aToluene, 110 °C; bDIBAL, THF, −78 °C; cAc2O, Py.; d...
Scheme 74: Final steps of Fukuyama’s synthesis.
Scheme 75: “Crisscross annulation”.
Scheme 76: Synthesis of 274; the 8-membered ring 274 was made using a crisscross annulation. a20% Pd(OH)2/C, H2...
Scheme 77: Conformational analysis of compound 273 and 275.
Scheme 78: Synthesis of a mitomycin analog. aNa2S2O4, H2O, DCM; bBnBr (10 equiv), K2CO3, 18-crown-6 (cat.), TH...
Scheme 79: Vedejs retrosynthesis.
Scheme 80: Formation of the azomethine ylide.
Scheme 81: Vedejs second synthesis of an aziridinomitosene. aDIBAL; bTPAP, NMO; c287; dTBSCl, imidazole.
Scheme 82: Trityl deprotection and new aziridine protecting group 300.
Scheme 83: Ene reaction towards benzazocinones.
Scheme 84: Benzazocenols via homo-Brook rearrangement.
Scheme 85: Pt-catalyzed [3+2] cycloaddition.
Scheme 86: Carbonylative lactamization entry to benzazocenols. aZn(OTf)2, (+)-N-methylephedrine, Et3N, TMS-ace...
Scheme 87: 8 membered ring formation by RCM. aBOC2O, NaHCO3; bTBSCl, Imidazole, DMF; callyl bromide, NaH, DMF; ...
Scheme 88: Aziridinomitosene synthesis. aTMSN3; bTFA; cPOCl3, DMF; dNaClO2, NaH2PO4, 2-methyl-2-butene; eMeI, ...
Scheme 89: Metathesis from an indole.
Scheme 90: Synthesis of early biosynthetic intermediates of mitomycins.
Beilstein J. Org. Chem. 2008, 4, No. 38, doi:10.3762/bjoc.4.38
Graphical Abstract
Scheme 1: Cyclopropylmethyl–homoallyl and nortricyclyl–norbornenyl radical systems.
Scheme 2: Deoxygenation-rearrangement-electrophile trapping.
Figure 1: Radical SOMO/α-nitrogen lone-pair interaction in the rearranged radical 7.
Figure 2: Other products obtained from xanthate 5 by tandem deoxygenation–rearrangement–electrophile trapping....
Scheme 3: Asymmetric hydroboration–oxidation of alkenes 14, 16 and 18.
Scheme 4: Deoxygenation–rearrangement–isomerisation of xanthates 20 and 23.
Scheme 5: Deoxygenation–rearrangement–electrophile trapping of xanthates 20 and 23.
Scheme 6: 2-Azabenzonorbornene as a masked pyrrolidine.
Scheme 7: Ring-opening–hydration–oxidation of azacycle 8.
Scheme 8: Preparation of trisubstituted pyrrolidine (+)-36.
Scheme 9: Preparation of pyrrolidine diester (+)-35 from Vince’s lactam 37.
Scheme 10: Acid-catalysed ring-opening–oxidation of azacycle (+)-8.
Scheme 11: Birch reduction of (+)-8 and 10.
Beilstein J. Org. Chem. 2008, 4, No. 3, doi:10.1186/1860-5397-4-3
Graphical Abstract
Scheme 1: Donohoe's approach to (±)-1-epiaustraline utilising a modified Birch reduction.
Scheme 2: Reaction conditions i) Zn, HCl (aq).
Scheme 3: Reaction conditions: i) ref. [10] ii) ref. [11] iii) Zn, conc. HCl(aq).
Scheme 4: Potential mechanism for α-ketopyrrole reduction..
Scheme 5: Alternative reduction pathway.
Scheme 6: Catalytic hydrogenation.
Scheme 7: Reaction conditions: i) DIBAL-H, CH2Cl2, -78 °C, 1 h then triethylphosphonoacetate, NaH, THF, −78 °...
Scheme 8: i) ref. [17].
Scheme 9: i) CH3OH, Zn, conc. HCl(aq) ii) H2 (40 psi), Pd/C, EtOH, 2M HCl.