Mechanisms for radical reactions initiating from N-hydroxyphthalimide esters

• Carlos R. Azpilcueta-Nicolas and
• Jean-Philip Lumb

Beilstein J. Org. Chem. 2024, 20, 346–378, doi:10.3762/bjoc.20.35

• ] (Scheme 11A). This transformation occurred under light irradiation either in the presence or absence of a RuII photoredox catalyst. It was found that the chiral lithium phosphate catalyst (R)-TRIP-Li played a crucial role in accelerating the reaction rate. Following an in-depth analysis of the mechanism

• substitution with alcohol 94 in the presence of lithium phthalimide 95 leads to product 96 and turns over the catalytic cycle. Importantly, species 93 can be detected by high resolution mass spectrometry, when the reaction is carried out without nucleophile and using stoichiometric amounts of PTH1. H. Fu and

Aldiminium and 1,2,3-triazolium dithiocarboxylate zwitterions derived from cyclic (alkyl)(amino) and mesoionic carbenes

• Nedra Touj,
• François Mazars,
• Guillermo Zaragoza and
• Lionel Delaude

Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145

• (−)-menthone was obtained in a separate step by deprotonating the corresponding aldiminium triflate with lithium diisopropylamide (LDA) at −78 °C [8]. Herein, we disclose the synthesis of three CAAC·CS2 and six MIC·CS2 inner salts from the corresponding aldiminium or 1,2,3-triazolium salts and carbon disulfide

Biphenylene-containing polycyclic conjugated compounds

• Cagatay Dengiz

Beilstein J. Org. Chem. 2023, 19, 1895–1911, doi:10.3762/bjoc.19.141

• subjecting α,α,α′,α′-tetrabromo-o-xylene (16) to t-BuOK to anhydrous conditions, biphenylene derivative 17 was obtained with a yield of 69% (Scheme 3). In the final step of the synthesis, a halogen–lithium exchange was carried out, followed by treatment with MeOH, resulting in a 79% yield of benzo[b

• , resulting in the formation of compound 75. Further transformation through lithium–halogen exchange, followed by reaction with Me3SiCl, yielded bis(trimethylsilylated) intermediate 76 in a 90% yield. By utilizing the conditions outlined in the prior investigation [49], compound 76 was subjected to a reaction

Recent advancements in iodide/phosphine-mediated photoredox radical reactions

• Tinglan Liu,
• Yu Zhou,
• Junhong Tang and
• Chengming Wang

Beilstein J. Org. Chem. 2023, 19, 1785–1803, doi:10.3762/bjoc.19.131

• electrophile compared to other alkyl halides, such as related bromides and chlorides. As a result, an effective iododecarboxylation provides a versatile platform for a range of decarboxylative reactions. Shang and co-workers recently found that aliphatic carboxylates and lithium iodide could undergo

A deep-red fluorophore based on naphthothiadiazole as emitter with hybridized local and charge transfer and ambipolar transporting properties for electroluminescent devices

• Suangsiri Arunlimsawat,
• Patteera Funchien,
• Pongsakorn Chasing,
• Atthapon Saenubol,
• Taweesak Sudyoadsuk and
• Vinich Promarak

Beilstein J. Org. Chem. 2023, 19, 1664–1676, doi:10.3762/bjoc.19.122

• increasing voltage (CELIV) or MIS-CELIV technique [59][60][61]. Electron- and hole-only MIS devices were fabricated with the structures of indium tin oxide (ITO)/magnesium fluoride (MgF2) (20 nm)/TPECNz (100 nm)/lithium fluoride (LiF) (1 nm)/aluminum (Al) (100 nm) and ITO/MgF2 (20 nm)/TPECNz (100 nm

α-(Aminomethyl)acrylates as acceptors in radical–polar crossover 1,4-additions of dialkylzincs: insights into enolate formation and trapping

• Angel Palillero-Cisneros,
• Paola G. Gordillo-Guerra,
• Fernando García-Alvarez,
• Olivier Jackowski,
• Franck Ferreira,
• Fabrice Chemla,
• Joel L. Terán and
• Alejandro Perez-Luna

Beilstein J. Org. Chem. 2023, 19, 1443–1451, doi:10.3762/bjoc.19.103

• allylation of lithium (trimethylsilyl)amides prepared in situ from the parent amines by a lithiation/silylation/lithiation sequence (Table 1). Using this protocol, α-(aminomethyl)acrylates 5 and 6 derived from benzhydrylamine and aniline were prepared in high yields (Table 1, entries 1 and 2). The procedure

Application of N-heterocyclic carbene–Cu(I) complexes as catalysts in organic synthesis: a review

• Nosheen Beig,
• Varsha Goyal and
• Raj K. Bansal

Beilstein J. Org. Chem. 2023, 19, 1408–1442, doi:10.3762/bjoc.19.102

• –Cu(I) complexes 12 (Scheme 5). A variety of bases, namely metal alkoxides, alkali metal carbonates, n-butyllithium, and lithium bis(trimethylsilyl)amide have been employed for this purpose. In 2010, Diez-González et al. synthesized a variety of NHC–Cu(I) complexes 14 from imidazolium salts 13 using

• diaminocarbenes) Cu(I) hexamethyldisilazide complexes by using lithium hexamethyldisilazide as a base in 2017 (Scheme 15) [29]. The initially formed NHC–CuCl complexes 41, 44, and 47 reacted with another molecule of LiN(SiMe3)2 to undergo nucleophilic substitution of Cl by a bis(trisilyl)amino group to furnish

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

• also achieved in the last step (Figure 5) [73]. DIBALH (diisobutylaluminium hydride) in toluene was added to hexadecanol in dichloromethane at 0 °C (Figure 5) to form in situ a lithium alcoholate. Then, S-glycidol was added at rt to produce in 50% yield the diol 5.2 after a regioselective opening of

• the epoxide. The lithium salts were removed by washing with potassium sodium tartrate (Seignette’s salt). Then, at low temperature an excess of 2-chloro-1,3,2-dioxaphospholane (5.3, 3.8 equiv) in the presence of diisopropylethylamine (DIPEA) reacted with the primary alcohol to produce, after an

• presence of dimethylaminopyridine (DMAP). Then, 27.2 reacted with potassium thioacetate to produce the thioester 27.3. Its reduction with lithium aluminium hydride produced the free thiol 27.4 that was used as nucleophile on octadecyl iodide to install the C18 lipid chain. The deprotection of the primary

Radical ligand transfer: a general strategy for radical functionalization

• David T. Nemoto Jr,
• Kang-Jie Bian,
• Shih-Chieh Kao and
• Julian G. West

Beilstein J. Org. Chem. 2023, 19, 1225–1233, doi:10.3762/bjoc.19.90

• various acids with lead(IV) tetraacetate in the presence of lithium chloride (Scheme 4) [40][41]. Nucleophilic lithium chloride was used as the chlorine atom source for this transformation. In the representative scope of this transformation, primary and secondary chlorides could be formed in relatively

Enabling artificial photosynthesis systems with molecular recycling: A review of photo- and electrochemical methods for regenerating organic sacrificial electron donors

• Grace A. Lowe

Beilstein J. Org. Chem. 2023, 19, 1198–1215, doi:10.3762/bjoc.19.88

• discharge and charge the donor-containing organic phase (Figure 2A) [34]. The first solution contained an organic lithium salt and a hydrogen-evolution catalyst which could generate hydrogen via a light-driven or dark process. The second solution contained an organic chloride salt and a water oxidation

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

• half potential (*E1/2 = −3.36 V vs SCE) even more negative than alkali metals including lithium, making it one of the most potent chemical reductants ever reported. Owing to this exceptional reductive redox power, hydrodehalogenation of various electron-poor and electron-rich aryl bromides and

• direct application of commercially available potassium (poly)sulfide (K2Sx) with H2O, the top-down generation from elemental sulfur (S8) with sodium tert-butoxide (NaOt-Bu), and the bottom-up generation from lithium sulfide (Li2S) or triisopropylsilanethiol (iPr3SiSH) were all suitable methods of

Strategies in the synthesis of dibenzo[b,f]heteropines

• David I. H. Maier,
• Barend C. B. Bezuidenhoudt and
• Charlene Marais

Beilstein J. Org. Chem. 2023, 19, 700–718, doi:10.3762/bjoc.19.51

• from 2-bromostyrene (116) via halogen–lithium exchange and quenching with the appropriate heteroatom source (SiR2Cl2, SnMe2Cl2, GeR2Cl2, BBr3). P-Tethered dienes were synthesised via quenching of a 2-vinylphenyl Grignard reagent with phenylphosphonic dichloride (PhPOCl2). O-Tethered dienes were

• authors brominated 2a in acetic acid, resulting in a tetrabrominated intermediate 154 in excellent yield (90%). Selective lithium–halogen exchange and reaction with a chlorophosphine, followed by debromination with BuLi/MeOH, gave the desired bisphosphine 155 in good yield (Scheme 36). Conclusion The

Enolates ambushed – asymmetric tandem conjugate addition and subsequent enolate trapping with conventional and less traditional electrophiles

• Péter Kisszékelyi and
• Radovan Šebesta

Beilstein J. Org. Chem. 2023, 19, 593–634, doi:10.3762/bjoc.19.44

• trapping by adding MeLi (1.05 equiv), which indeed led to a significant increase in yield and selectivity due to the high reactivity of the lithium dialkyl zincate enolate. Various 1,3-diketones 39 were prepared using this method with good yields and excellent enantioselectivities while only the trans

• desymmetrization step during which the chiral enolate attacks (Si-face) the prochiral cyclohexadienone ring via a chair-like transition state. The reaction requires an excess amount of base, resulting in the formation of a more favorable lithium enolate. Subsequent oxidation of the boronates gave the corresponding

Strategies to access the [5-8] bicyclic core encountered in the sesquiterpene, diterpene and sesterterpene series

• Cécile Alleman,
• Charlène Gadais,
• Laurent Legentil and
• François-Hugues Porée

Beilstein J. Org. Chem. 2023, 19, 245–281, doi:10.3762/bjoc.19.23

• cyclopropane 185 was performed with lithium in liquid ammonia in order to introduce the angular methyl group. In the same time, the ketone was reduced into an alcohol, which one was submitted to Barton deoxygenation. The alkene side chain underwent a metathesis reaction with methyl methacrylate to introduce an

Friedel–Crafts acylation of benzene derivatives in tunable aryl alkyl ionic liquids (TAAILs)

• Swantje Lerch,
• Stefan Fritsch and
• Thomas Strassner

Beilstein J. Org. Chem. 2023, 19, 212–216, doi:10.3762/bjoc.19.20

• lithium bis(trifluoromethylsulfonyl)imide (LiNTf2). All reactions are generally tolerant towards different aryl substitutions, substitution patterns, alkyl chain lengths and can be carried out in a multigram scale [57]. The acylation of the electron-rich benzene derivative anisole with acetic anhydride

Germacrene B – a central intermediate in sesquiterpene biosynthesis

• Houchao Xu and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 186–203, doi:10.3762/bjoc.19.18

• -workers [19], through a sequence of reduction to the alcohol, acetylation and reduction with lithium in ammonia (Scheme 3A) [20], and its structure was unambiguously assigned by X-ray crystallography of a silver nitrate adduct [21]. From natural sources, the compound was first obtained from Humulus

Synthetic study toward tridachiapyrone B

• Morgan Cormier,
• Florian Hernvann and
• Michaël De Paolis

Beilstein J. Org. Chem. 2022, 18, 1741–1748, doi:10.3762/bjoc.18.183

• chiral tetrahydrofuran (Scheme 1b). To assemble the skeleton of the natural product, we developed a new strategy in which the α,α’-dimethoxy-γ-pyrone motif 2 was first desymmetrized by a sequence encompassing the conjugate addition of 2-lithio-1,3-dithiane, elimination of methoxide lithium, and

• ambitious coupling, however, met a dead-end and a less direct approach was explored. With a more reactive and less hindered nucleophile, we explored the coupling of lithiocyclopentadiene to compound 2. After conjugate addition and elimination of lithium methoxide, the resulting 6a would be deprotonated by

Synthesis of (−)-halichonic acid and (−)-halichonic acid B

• Keith P. Reber and
• Emma L. Niner

Beilstein J. Org. Chem. 2022, 18, 1629–1635, doi:10.3762/bjoc.18.174

• hydrolysis of compounds 8 and 9 to form the corresponding amino acids. Thus, treating bicycle 8 with aqueous lithium hydroxide resulted in hydrolysis of the ethyl ester, and subsequent neutralization with pH 7 phosphate buffer afforded halichonic acid ((−)-1) in 88% yield after purification by column

Synthetic study toward the diterpenoid aberrarone

• Liang Shi,
• Zhiyu Gao,
• Yiqing Li,
• Yuanhao Dai,
• Yu Liu,
• Lili Shi and
• Hong-Dong Hao

Beilstein J. Org. Chem. 2022, 18, 1625–1628, doi:10.3762/bjoc.18.173

• through the corresponding lithium enolate occurred from the convex face of the bicyclic ring system [37]. After these two continuous stereocenters were successfully installed, the expected challenging all-carbon quaternary center at C1 was constructed utilizing the Nagata reagent (Et2AlCN). By using this

Preparation of β-cyclodextrin-based dimers with selectively methylated rims and their use for solubilization of tetracene

• Konstantin Lebedinskiy,
• Volodymyr Lobaz and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2022, 18, 1596–1606, doi:10.3762/bjoc.18.170

• deacetylation of 8, proved to be not reactive enough to complete the reaction in 24 h under the conditions used to prepare the dimer 5. The prolongation of the reaction time increased the yield slightly, but it was still too low (17%). To improve the yield, we used lithium iodide and increased the temperature

Synthesis of the biologically important dideuterium-labelled adenosine triphosphate analogue ApppI(d₂)

• Petri A. Turhanen

Beilstein J. Org. Chem. 2022, 18, 1466–1470, doi:10.3762/bjoc.18.153

• -enoic acid (2) was then reduced to 3-methylbut-3-en-1,1-d2-1-ol (3) with lithium aluminium deuteride, followed by tosylation with tosyl chloride. Tosylated 3-methylbut-3-en-1,1-d2-1-ol 4 was then treated with ATP TBA salt in acetonitrile at 45 °C for 55 h to give the target product ApppI(d2) (Scheme 1

Preparation of an advanced intermediate for the synthesis of leustroducsins and phoslactomycins by heterocycloaddition

• Anaïs Rousseau,
• Guillaume Vincent and
• Cyrille Kouklovsky

Beilstein J. Org. Chem. 2022, 18, 1385–1395, doi:10.3762/bjoc.18.143

• [30][31]. However, condensation of the corresponding lithium acetylide to the ketone 11b gave modest and non-reproducible yields of the desired product 22 (Scheme 7, Table 1). The configuration of the newly created stereogenic center was undetermined. These experiments showed the necessity to perform

Ionic multiresonant thermally activated delayed fluorescence emitters for light emitting electrochemical cells

• Merve Karaman,
• Abhishek Kumar Gupta,
• Subeesh Madayanad Suresh,
• Tomas Matulaitis,
• Lorenzo Mardegan,
• Daniel Tordera,
• Henk J. Bolink,
• Sen Wu,
• Stuart Warriner,
• Ifor D. Samuel and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2022, 18, 1311–1321, doi:10.3762/bjoc.18.136

• operation. To solve this, we fabricated devices adding an ionic liquid (lithium hexafluorophosphate (LiPF6) or 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM:PF6) in a 4 to 1 molar ratio) and, in some cases, an electrolyte matrix (PEO (polyethylene oxide)), to improve the ionic mobility on the active

Modular synthesis of 2-furyl carbinols from 3-benzyldimethylsilylfurfural platforms relying on oxygen-assisted C–Si bond functionalization

• Sebastien Curpanen,
• Per Reichert,
• Gabriele Lupidi,
• Giovanni Poli,
• Julie Oble and
• Alejandro Perez-Luna

Beilstein J. Org. Chem. 2022, 18, 1256–1263, doi:10.3762/bjoc.18.131

• alkoxides We first contemplated the possibility to promote C3–Si bond functionalization through intramolecular activation by alkoxides [15]. It was reported that lithium alkoxides A undergo 1,4-silyl migration (Brook rearrangement) to generate C2-lithiated furans C, which in turn can react in the presence

Vicinal ketoesters – key intermediates in the total synthesis of natural products

• Marc Paul Beller and
• Ulrich Koert

Beilstein J. Org. Chem. 2022, 18, 1236–1248, doi:10.3762/bjoc.18.129

• with Davis’ oxaziridine and subsequent oxidation using Dess–Martin periodinane. Initial attempts for the key step (15 → 16) like a Nozaki–Hiyama–Kishi reaction failed, but lithium–halogen exchange using t-BuLi at low temperatures gave the desired vinyllithium intermediate I which successfully added to

• also be used in photochemical reactions, as shown by Gramain et al. in the synthesis of the pyrrolizidine alkaloid (rac)-isoretronecanol (69, Scheme 11) [26]. A Claisen condensation of the lithium enolate of N-acetylpyrrolidine (66) with diethyl oxalate gave the ketoester 67. Irradiation of compound 67