A Paradigm Shift in Catalysis: Electro- and Photomediated Nickel-Catalyzed Cross-Coupling Reactions

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 56(20), P. 2851 - 2865

Published: Sept. 29, 2023

ConspectusTransition-metal catalyzed cross-coupling reactions are fundamental in organic chemistry, facilitating strategic bond formations for accessing natural products, materials, agrochemicals, and pharmaceuticals. Redox chemistry enables access to elusive mechanisms through single-electron processes as an alternative classical two-electron strategies predominated by palladium catalysis. The seminal reports of Baran, MacMillan, Doyle, Molander, Weix, Lin, Fu, Reisman, others merging redox perturbation (photochemical, electrochemical, purely chemical) with catalysis pivotal the current resurgence mechanistic understanding first-row transition metal-based hallmark this platform is systematic modulation transition-metal oxidation states a photoredox catalyst or at heterogeneous electrode surface. Electrocatalysis photocatalysis enhance metal catalysis' capacity formation electron- energy-transfer that promote otherwise challenging elementary steps mechanisms. Cross-coupling conditions promoted electrocatalysis mild, proceeds exceptionally high chemoselectivity wide functional group tolerance. interfacing abundant has brought about paradigm shift technology practitioners quickly applying these tools synthesizing fine chemicals pharmaceutically relevant motifs. In particular, merger Ni electro- photochemistry ushered new era carbon-carbon carbon-heteroatom cross-couplings expanded generality compared their thermally driven counterparts. Over past decade, we have developed enabling photo- electrochemical methods throughout our combined research experience industry (BMS, AstraZeneca) academia (Professor Scripps Research) cross-disciplinary collaborative environments. Account, will outline recent progress from present laboratories electrochemically mediated Ni-catalyzed cross-couplings. By highlighting methodologies, also compare features both photochemical forging C(sp2)-C(sp3), C(sp3)-C(sp3), C-O, C-N, C-S bonds. Through side-by-side comparisons, hope demystify subtle differences between two complementary enact control over Finally, building off collective ourselves rest community, propose tactical user guide aid practitioner rapidly such synthetic designs.

Language: Английский

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Photoinduced Electron Transfer from Xanthates to Acyl Azoliums: Divergent Ketone Synthesis via N‐Heterocyclic Carbene Catalysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(32)

Published: June 12, 2023

Considering the prevalence of alcohols and carboxylic acids, their fragment cross-coupling reactions could hold significant implications in organic synthesis. Herein, we report a versatile method for synthesizing diverse range ketones from acid derivatives via N-heterocyclic carbene (NHC) catalysis. Mechanistic investigations revealed that photoexcited xanthates acyl azoliums undergo single electron transfer (SET) under photocatalyst-free conditions, generating NHC-derived ketyl radicals alkyl radicals. These open-shell intermediates subsequently radical-radical reaction, yielding valuable ketones. Furthermore, this approach can be employed three-component involving alkenes enynes, resulting structurally cross-coupled The unified strategy offers unique opportunity coupling derivatives, accommodating functional groups even complex settings.

Language: Английский

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Decarboxylative, Radical C–C Bond Formation with Alkyl or Aryl Carboxylic Acids: Recent Advances

Synthesis, Journal Year: 2023, Volume and Issue: 55(20), P. 3239 - 3250

Published: April 26, 2023

Abstract The ubiquity of carboxylic acids as naturally derived or man-made chemical feedstocks has spurred the development powerful, decarboxylative C–C bond-forming transformations for organic synthesis. Carboxylic benefit not only from extensive commercial availability, but are stable surrogates organohalides organometallic reagents in transition-metal-catalysed cross-coupling. Open shell reactivity (or derivatives thereof) to furnish carbon-centred radicals is proving transformative synthetic chemistry, enabling novel and strategy-level C(sp3)–C bond disconnections with exquisite chemoselectivity. This short review will summarise several latest advances this ever-expanding area. 1 Introduction 2 Improved Decarboxylative Arylations 3 sp3–sp3 Cross-Coupling Acids Aliphatic Bromides 4 Alcohols Amines 5 Doubly 6 Bond Formation (Hetero)aryl 7 Conclusions

Language: Английский

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Stereoretentive Post-Translational Protein Editing

ACS Central Science, Journal Year: 2023, Volume and Issue: 9(3), P. 405 - 416

Published: Feb. 24, 2023

Chemical post-translational methods allow convergent side-chain editing of proteins without needing to resort genetic intervention. Current approaches that the creation constitutionally native side chains via C-C bond formation, using off-protein carbon-centered C· radicals added unnatural amino acid radical acceptor (SOMOphile, singly occupied molecular orbital (SOMO)) "tags" such as dehydroalanine, are benign and wide-ranging. However, they also typically create epimeric mixtures d/l-residues. Here, we describe a light-mediated desulfurative method that, through reaction stereoretained on-proteinl-alanyl Cβ· radicals, allows Cβ-Hγ, Cβ-Oγ, Cβ-Seγ, Cβ-Bγ, Cβ-Cγ formation flexibly generate site-selectively edited with full retention stereochemistry under mild conditions from natural precursor. This methodology shows great potential explore protein diversity function in construction useful bioconjugates.

Language: Английский

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Cross-Coupling of Amines via Photocatalytic Denitrogenation of In Situ Generated Diazenes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(21), P. 11524 - 11529

Published: May 18, 2023

A method for C(sp

Language: Английский

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