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Search for "mechanistic insights" in Full Text gives 34 result(s) in Beilstein Journal of Organic Chemistry.
Beyond catalyst deactivation: cross-metathesis involving olefins containing N-heteroaromatics
- Kevin Lafaye,
- Cyril Bosset,
- Lionel Nicolas,
- Amandine Guérinot and
- Janine Cossy
Beilstein J. Org. Chem. 2015, 11, 2223–2241, doi:10.3762/bjoc.11.241
- of N-heteroaromatics containing olefins in metathesis has been less documented. In this review, we would like to give an overview of successful metatheses involving alkenes that possess N-heteroaromatics in order to delineate some guidelines. Some mechanistic insights dealing with catalyst
- deactivation caused by amino derivatives will be first presented and discussed. RCM and CM involving alkenes possessing N-heteroaromatics will be then successively examined [38]. Review Mechanistic insights into amine-induced catalyst deactivation Recently, intensive studies dealing with ruthenium catalyst
Graphical Abstract
Figure 1: Some ruthenium catalysts for metathesis reactions.
Scheme 1: Decomposition of methylidenes 1 and 2.
Scheme 2: Deactivation of G-HII in the presence of ethylene.
Scheme 3: Reaction between GI/GII and n-BuNH2.
Scheme 4: Reaction of GII with amines a–d.
Scheme 5: Amine-induced decomposition of GII methylidene 2.
Scheme 6: Amine-induced decomposition of GII in RCM conditions.
Scheme 7: Deactivation of methylidene 2 in the presence of pyridine.
Scheme 8: Reaction of G-HII with various amines.
Scheme 9: Formation of olefin 22 from styrene.
Scheme 10: Hypothetic deactivation pathway of G-HII.
Scheme 11: RCM of dienic pyridinium salts.
Scheme 12: Synthesis of polycyclic scaffolds using RCM.
Scheme 13: Enyne ring-closing metathesis.
Scheme 14: Synthesis of (R)-(+)-muscopyridine using a RCM strategy.
Scheme 15: Synthesis of a tris-pyrrole macrocycle.
Scheme 16: Synthesis of a bicyclic imidazole.
Scheme 17: RCM using Schrock’s catalyst 44.
Scheme 18: Synthesis of 1,6-pyrido-diazocine 46 by using a RCM.
Scheme 19: Synthesis of fused pyrimido-azepines through RCM.
Scheme 20: RCM involving alkenes containing various N-heteroaromatics.
Scheme 21: Synthesis of dihydroisoquinoline using a RCM.
Scheme 22: Formation of tricyclic compound 59.
Scheme 23: RCM in the synthesis of normuscopyridine.
Scheme 24: Synthesis of macrocycle 64.
Scheme 25: Synthesis of macrocycles possessing an imidazole group.
Scheme 26: Retrosynthesis of an analogue of erythromycin.
Scheme 27: Retrosynthesis of haminol A.
Scheme 28: CM involving 3-vinylpyridine 70 with 71 and vinylpyridine 70 with 73.
Scheme 29: Revised retrosynthesis of haminol A.
Scheme 30: CM between 78 and crotonaldehyde.
Scheme 31: Hypothesized deactivation pathway.
Scheme 32: CM involving an allyl sulfide containing a quinoline.
Scheme 33: CM involving allylic sulfide possessing a quinoxaline or a phenanthroline.
Scheme 34: CM between an acrylate and a 2-methoxy-5-bromo pyridine.
Scheme 35: Successful CM of an alkene containing a 2-chloropyridine.
Scheme 36: Variation of the substituent on the pyridine ring.
Scheme 37: CM involving alkenes containing a variety of N-heteroaromatics.
Further exploration of the heterocyclic diversity accessible from the allylation chemistry of indigo
- Alireza Shakoori,
- John B. Bremner,
- Mohammed K. Abdel-Hamid,
- Anthony C. Willis,
- Rachada Haritakun and
- Paul A. Keller
Beilstein J. Org. Chem. 2015, 11, 481–492, doi:10.3762/bjoc.11.54
- unprecedented heterocycles, optimised procedures of some previously reported structures to now produce synthetically useful yields, and the efficient syntheses of additional polycyclic heterocycles. These results lead to substantial new mechanistic insights, an assessment of the potential to further increase
Graphical Abstract
Scheme 1: The synthesis of N-monoallylated indigo derivatives.
Scheme 2: The synthesis of 8a-hydroxyazepinodiindolones.
Figure 1: The structure and X-ray crystal structure (ball and stick representation) of azepinodiindolone 7. T...
Figure 2: Dihydroazepino[1,2-a:3,4-b']diindolones from Nb-acyl-L-tryptophanamides [5].
Scheme 3: The optimal synthesis of spiro heterocycles 12–16, and spiro/polyfused ring heterocycles 17 and 18 ...
Scheme 4: The synthesis of the oxa-bridged azepinodiindolone 22 from indigo and 1-bromo-3-methylbut-2-ene.
Figure 3: Modelled structure (Spartan 10, v1.1.0, Wavefunction Inc) of bridged indigo-tetrahydrofuran product ...
Scheme 5: The reaction of indigo with cinnamyl bromide yielding two spiro-based derivatives.
Figure 4: Structural analysis of compound 23. Left: modelled structure showing the cisoid configuration of th...
Scheme 6: Proposed mechanism for the synthesis of the red diindolone heterocycles and the azepinodiindolones.
Scheme 7: Proposed mechanism for the formation of 22. The order of protonation and allylation is undetermined....
Scheme 8: Proposed mechanism for the formation of 23 from intermediate 29.
Scheme 9: Proposed key branch points and mechanistic sinks in the base-catalysed cascade allylation reactions...
Scheme 10: Reaction of the spiro heterocycle 12 with Grubbs' II catalyst, and X-ray crystal structure of the n...
Recent applications of the divinylcyclopropane–cycloheptadiene rearrangement in organic synthesis
- Sebastian Krüger and
- Tanja Gaich
Beilstein J. Org. Chem. 2014, 10, 163–193, doi:10.3762/bjoc.10.14
- overview of the new mechanistic insights concerning the title reaction is provided as well as a condensed account on the biological relevance of the topic. Heteroatom variants of this rearrangement are covered briefly. Keywords: cycloheptadiene; divinylcyclopropane rearrangement; domino reactions; natural
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.
Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition
- Regina Berg and
- Bernd F. Straub
Beilstein J. Org. Chem. 2013, 9, 2715–2750, doi:10.3762/bjoc.9.308
Graphical Abstract
Scheme 1: Exemplary 1,3-dipolar cycloaddition of phenylacetylene with phenyl azide [6].
Scheme 2: CuAAC reaction of benzyl azide with (prop-2-yn-1-yloxy)benzene [12].
Scheme 3: Bioconjugation reaction of capsid-bound azide groups with alkynyl-functionalized dye molecules (cow...
Figure 1: Tris(triazolylmethyl)amine ligands for CuAAC applications in bioorganic chemistry: TBTA = tris[(1-b...
Figure 2: Derivatives of 2,2’-bipyridine and 1,10-phenanthroline, commonly used ligands in CuAAC reactions un...
Scheme 4: CuAAC reaction with copper(II) precursor salt and rate-accelerating monodentate phosphoramidite lig...
Scheme 5: Synthesis of 1-(adamant-1-yl)-1H-1,2,3-triazol-4-ylcarbonyl-Phe-Gly-OH by solid-supported Click cat...
Scheme 6: CuAAC reaction with re-usable copper(I)-tren catalyst [129].
Scheme 7: CuAAC test reaction with chlorido[tris(1-benzyl-1H-1,2,3-triazol-4-yl)methanol-κ3N3]copper(I) and a...
Scheme 8: CuAAC model reaction with [Cu2(μ-TBTA-κ4N2,N3,N3’,N3’’)2][BF4]2 [131].
Scheme 9: Application of a (2-aminoarenethiolato)copper(I) complex as homogeneous catalyst for the CuAAC test...
Scheme 10: Application of [CuBr(PPh3)3] as homogeneous catalyst for the CuAAC test reaction of benzyl azide wi...
Figure 3: Phosphinite and phosphonite copper(I) complexes presented by Díez-González [144].
Scheme 11: Effect of additives on the CuAAC test reaction with [(SIMes)CuCl] [149].
Scheme 12: Initiation of the catalytic cycle by formation of the copper acetylide intermediate from [(ICy)2Cu]...
Scheme 13: Early mechanistic proposal by Sharpless [12,42].
Scheme 14: Chemoselective synthesis of a 5-iodo-1,4-disubstituted 1,2,3-triazole [156].
Scheme 15: Mechanistic proposals for the copper-catalyzed azide–iodoalkyne cycloaddition [156].
Scheme 16: 1,3-Dipolar cycloaddition of 3-hexyne catalyzed by [(SIMes)CuBr] [146].
Scheme 17: Mechanistic picture for the cycloaddition of internal alkynes catalyzed by NHC-copper(I) complexes ...
Scheme 18: Catalytic cycle of the CuAAC reaction on the basis of the proposed mechanistic scheme by Fokin and ...
Figure 4: Schematic representation of the single crystal X-ray structures of copper(I) acetylide complexes [Cu...
Figure 5: Acetylide-bridged dicopper complexes with tris(heteroarylmethyl)amine ligand(s) as key intermediate...
Scheme 19: Off-cycle equilibrium between unreactive polymeric copper(I) acetylide species (right) and reactive...
Figure 6: Categories of tris(heteroarylmethyl)amine ligands regarding their binding ability to copper(I) ions ...
Scheme 20: Mechanistic scheme for ligand-accelerated catalysis with tripodal tris(heteroarylmethyl)amine ligan...
Scheme 21: Synthesis of supposed intermediates in the CuAAC’s catalytic cycle [164,187].
Figure 7: Tetranuclear copper acetylide complexes as reported by Weiss (left) [176] and Tasker (middle) [185] and model...
Figure 8: Gibbs free energy diagram for the computed mechanistic pathway of the CuAAC reaction starting from ...
Figure 9: Energy diagram by Ahlquist and Fokin [125].
Scheme 22: Mechanistic proposal for the CuAAC reaction based on DFT calculations by Fokin [125] and our group [186] ([Cu...
Figure 10: ORTEP plot [202,203] of the X-ray powder diffraction crystal structure of (phenylethynyl)copper(I) [(PhC≡CCu)...
Scheme 23: Synthesis of [(PhC≡CCu)2]n as co-product in the Glaser coupling of phenylacetylene in the presence ...
Scheme 24: Mechanistic explanation for the isotopic enrichment in the product triazolide in the presence of th...
Scheme 25: Homogeneous CuAAC catalysis with a bistriazolylidene dicopper complex (0.5 mol %) and comparison wi...
Multigramme synthesis and asymmetric dihydroxylation of a 4-fluorobut-2E-enoate
- James A. B. Laurenson,
- John A. Parkinson,
- Jonathan M. Percy,
- Giuseppe Rinaudo and
- Ricard Roig
Beilstein J. Org. Chem. 2013, 9, 2660–2668, doi:10.3762/bjoc.9.301
- . Modifications of this type are sometimes accepted by sugar-processing enzymes such as the kinases and transferases involved in oligosaccharide assembly, or in antibiotic biosynthesis. Mechanistic insights, and new routes to hybrid natural products represent the rewards of this endeavour [1][2][3][4][5][6][7][8
Graphical Abstract
Scheme 1: Key steps from the synthesis of 6-fluoro-D-olivose (6) from D-glucose (1).
Scheme 2: De novo asymmetric syntheses of 6-deoxy-6-fluorohexoses [13].
Scheme 3: Fluorobutenoate building block 14, and related species 16 and 19 from the literature [14-16].
Scheme 4: Fluorobutenoate building blocks 25 and 26 prepared from crotonic acid.
Figure 1: Side product 27 isolated from attempted fluorination.
Figure 2: The ligand panel used in the asymmetric dihydroxylation studies. The bold oxygen shows the point of...
Scheme 5: Typical AD procedure; see Table 1 for outcomes.
Scheme 6: Conversion of enantiomerically-enriched diols to dibenzoates for HPLC analysis.
Figure 3: Diisopropyl L-tartrate (30) used as a chiral modifier for NMR determination of ee.
Figure 4: Partial 19F{1H} NMR spectra (376 MHz, L-(+)-DIPT/CDCl3, 300 K) spectra of (a) racemate 28c, (b) dio...
Figure 5: Partial 19F{1H} NMR (400 MHz, L-(+)-DIPT/CDCl3, 300 K) spectra of 28b and 28a using optimised condi...
Scheme 7: Applying cyclic sulfate methodology to gain access to anti-diastereoisomers (transformations were d...
Scheme 8: Protecting and chain extending the educts of asymmetric dihydroxylation.
New developments in gold-catalyzed manipulation of inactivated alkenes
- Michel Chiarucci and
- Marco Bandini
Beilstein J. Org. Chem. 2013, 9, 2586–2614, doi:10.3762/bjoc.9.294
- interest relying on the synthetic approach (a wide range of densely functionalized nitrogen-based heterocyclic cores (143) were readily accessible) (Scheme 35), intriguing mechanistic insights derived from a detailed investigation based on experimental and computational observations [79]. In particular
Graphical Abstract
Figure 1: Elementary steps in the gold-catalyzed nucleophilic addition to olefins.
Figure 2: Different approaches for the gold-catalyzed manipulation of inactivated alkenes.
Figure 3: Computed mechanistic cycle for the gold-catalyzed alkoxylation of ethylene with PhOH.
Scheme 1: [Au(I)]-catalyzed addition of phenols and carboxylic acids to alkenes.
Scheme 2: [Au(III)] catalyzed annulations of phenols and naphthols with dienes.
Scheme 3: [Au(III)]-catalyzed addition of aliphatic alcohols to alkenes.
Scheme 4: [Au(III)]-catalyzed carboalkoxylation of alkenes with dimethyl acetals 6.
Figure 4: Postulated mechanism for the [Au(I)]-catalyzed hydroamination of olefins.
Scheme 5: Isolation and reactivity of alkyl gold intermediates in the intramolecular hydroamination of alkene...
Scheme 6: [Au(I)]-catalyzed intermolecular hydroamination of dienes.
Scheme 7: Intramolecular [Au(I)]-catalyzed hydroamination of alkenes with carbamates.
Scheme 8: [Au(I)]-catalyzed inter- as well as intramolecular addition of sulfonamides to isolated alkenes.
Scheme 9: Intramolecular hydroamination of N-alkenylureas catalyzed by gold(I) carbene complex.
Scheme 10: Enantioselective hydroamination of alkenyl ureas with biphenyl tropos ligand and chiral silver phos...
Scheme 11: Intramolecular [Au(I)]-catalyzed hydroamination of N-allyl-N’-aryl ureas. (PNP = pNO2-C6H4, PMP = p...
Scheme 12: [Au(I)]-catalyzed hydroamination of alkenes with ammonium salts.
Scheme 13: Enantioselective [Au(I)]-catalyzed intermolecular hydroamination of alkenes with cyclic ureas.
Scheme 14: Mechanistic proposal for the cooperative [Au(I)]/menthol catalysis for the enantioselective intramo...
Scheme 15: [Au(III)]-catalyzed addition of 1,3-diketones to alkenes.
Scheme 16: [Au(I)]-catalyzed intramolecular addition of β-keto amides to alkenes.
Scheme 17: Intermolecular [Au(I)]-catalyzed addition of indoles to alkenes.
Scheme 18: Intermolecular [Au(III)]-catalyzed hydroarylation of alkenes with benzene derivatives and thiophene....
Scheme 19: a) Intramolecular [Au(III)]-catalyzed hydroarylation of alkenes. b) A SEAr-type mechanism was hypot...
Scheme 20: Intramolecular [Au(I)]-catalyzed hydroalkylation of alkenes with simple ketones.
Scheme 21: Proposed reaction mechanism for the intramolecular [Au(I)]-catalyzed hydroalkylation of alkenes wit...
Scheme 22: Tandem Michael addition/hydroalkylation catalyzed by [Au(I)] and [Ag(I)] salts.
Scheme 23: Intramolecular [Au(I)]-catalyzed tandem migration/[2 + 2] cycloaddition of 1,7-enyne benzoates.
Scheme 24: Intramolecular [Au(I)]-catalyzed cyclopropanation of alkenes.
Scheme 25: Stereospecificity in [Au(I)]-catalyzed hydroalkoxylation of allylic alcohols.
Scheme 26: Mechanistic investigation on the intramolecular [Au(I)]-catalyzed hydroalkoxylation of allylic alco...
Scheme 27: Mechanistic investigation on the intramolecular enantioselective [Au(I)]-catalyzed alkylation of in...
Scheme 28: Synthesis of (+)-isoaltholactone via stereospecific intramolecular [Au(I)]-catalyzed alkoxylation o...
Scheme 29: Intramolecular enantioselective dehydrative amination of allylic alcohols catalyzed by chiral [Au(I...
Scheme 30: Enantioselective intramolecular hydroalkylation of allylic alcohols with aldehydes catalyzed by 20c...
Scheme 31: Gold-catalyzed intramolecular diamination of alkenes.
Scheme 32: Gold-catalyzed aminooxygenation and aminoarylation of alkenes.
Scheme 33: Gold-catalyzed carboamination, carboalkoxylation and carbolactonization of terminal alkenes with ar...
Scheme 34: Synthesis of tricyclic indolines via gold-catalyzed formal [3 + 2] cycloaddition.
Scheme 35: Gold(I) catalyzed aminoarylation of terminal alkenes in presence of Selectfluor [dppm = bis(dipheny...
Scheme 36: Mechanistic investigation on the aminoarylation of terminal alkenes by bimetallic gold(I) catalysis...
Scheme 37: Proposed mechanism for the aminoarylation of alkenes via [Au(I)-Au(I)]/[Au(II)-Au(II)] redox cataly...
Scheme 38: Oxyarylation of terminal olefins via redox gold catalysis.
Scheme 39: a) Intramolecular gold-catalyzed oxidative coupling reactions with aryltrimethylsilanes. b) Oxyaryl...
Scheme 40: Oxy- and amino-arylation of alkenes by [Au(I)]/[Au(III)] photoredox catalysis.
Formal synthesis of (−)-agelastatin A: an iron(II)-mediated cyclization strategy
- Daisuke Shigeoka,
- Takuma Kamon and
- Takehiko Yoshimitsu
Beilstein J. Org. Chem. 2013, 9, 860–865, doi:10.3762/bjoc.9.99
- provided evidence that these byproducts were generated by the intramolecular cyclization of enone 10 with TMSCl in EtOH, suggesting that the FeCl2/TMSCl system also gave enone 10 in ca. 30% yield [37]. The present study on the aminohalogenation reaction of carbamate 8 has inspired mechanistic insights that
- elimination of hazardous synthetic processes enables the establishment of more robust strategies to access 1. Furthermore, the present study has allowed us to obtain mechanistic insights suggesting that N–iron species (i) has a metal-radical character. Much work is currently being undertaken to comprehend
Graphical Abstract
Scheme 1: Our first- [26] and second-generation [27] approaches to (−)-agelastatin A (1).
Scheme 2: The present iron(II)-mediated aminohalogenation of N-tosyloxycarbamate 8 providing key intermediate...
Scheme 3: Aminohalogenation of azidoformate 3 (2 g scale) under FeBr2/Bu4NBr conditions.
Figure 1: Byproducts formed by aminohalogenation of N-tosyloxycarbamate 8 with FeCl2/TMSCl in EtOH (see Table 1; ent...
Scheme 4: Plausible reaction pathways in the aminohalogenation of N-tosyloxycarbamate 8 with FeX2/Bu4NX.
Scheme 5: Plausible reaction pathway to produce compounds 9 and 10.
Natural product biosyntheses in cyanobacteria: A treasure trove of unique enzymes
- Jan-Christoph Kehr,
- Douglas Gatte Picchi and
- Elke Dittmann
Beilstein J. Org. Chem. 2011, 7, 1622–1635, doi:10.3762/bjoc.7.191
- nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) pathways and highlight the unique enzyme mechanisms that were elucidated or can be anticipated for the individual products. We further include ribosomal natural products and UV-absorbing pigments from cyanobacteria. Mechanistic insights
Graphical Abstract
Figure 1: Cyanobacteria proliferate in diverse habitats. A) Bloom-forming freshwater cyanobacteria of the gen...
Figure 2: Schematic representation of enzymatic domains in A) nonribosomal peptide synthetases (NRPS); B) pol...
Figure 3: Structures of NRPS and PKS products in freshwater cyanobacteria.
Figure 4: A) Synthesis of the Adda ((2S,3S,8S,9S)-3-amino-9-methoxy-2,6,8-trimethyl-10-phenyl-4,6-decadienoic...
Figure 5: Structures of NRPS and PKS products in marine cyanobacteria.
Figure 6: A) Formation of the trichloroleucyl starter unit of barbamide (7) synthesis through the non-heme ir...
Figure 7: Structures of NRPS and PKS products in terrestrial cyanobacteria.
Figure 8: Synthesis of the (2S,4S)-4-methylproline moiety of nostopeptolides A (13).
Figure 9: Structures of cyanobacterial peptides that are synthesized ribosomally and post-translationally mod...
Figure 10: Formation of ester linkages and ω-amide linkage in microviridins 17 by the ATP grasp ligases MvdD a...
Figure 11: Structures of cyanobacterial sunscreen compounds.
Alkene selenenylation: A comprehensive analysis of relative reactivities, stereochemistry and asymmetric induction, and their comparisons with sulfenylation
- Vadim A. Soloshonok and
- Donna J. Nelson
Beilstein J. Org. Chem. 2011, 7, 744–758, doi:10.3762/bjoc.7.85
- these reactions have not been completely understood [29][33]. A more detailed analysis of steric and electronic effects might provide helpful mechanistic insights to clarify this practically important issue. Previously, we demonstrated that additions to alkenes, which proceed through cyclic 3-membered
Graphical Abstract
Figure 1: Chiral aryl selenium electrophiles 1–3.
Scheme 1: Plausible mechanism of alkene selenenylation.
Figure 2: Plot of log krel values for PhSeCl addition to alkenes versus their corresponding IEs. Point number...
Figure 3: Plot of log krel values for PhSeCl addition to alkenes versus their corresponding HOMOs, analogous ...
Figure 4: Plot of log krel versus HOMO shows data grouped by branching at α position. Data are from Table 3; point n...
Scheme 2: Major products from reactions of 1 and 2 with representative alkenols.
Figure 5: Structure of intermediate complex 9.
Figure 6: Plot of log krel values for PhSCl addition to alkenes versus their IEs. Data are from Table 6.
