Direct Synthesis of Polysubstituted Aldehydes via Visible-Light Catalysis
作者:Fengjin Wu、Leifeng Wang、Jiean Chen、David A. Nicewicz、Yong Huang
DOI:10.1002/anie.201712384
日期:2018.2.19
competing reaction pathways, commercial styrenes react with vinyl ethers selectively in the presence of an acridinium salt photooxidant and a disulfide hydrogen‐atom‐transfer catalyst under blue LED irradiation. Alkyl aldehydes with different substitution patterns are prepared in good yields. This strategy can be applied to structurally sophisticated substrates.
A General Organocatalytic System for Enantioselective Radical Conjugate Additions to Enals
作者:Emilien Le Saux、Dengke Ma、Pablo Bonilla、Catherine M. Holden、Danilo Lustosa、Paolo Melchiorre
DOI:10.1002/anie.202014876
日期:2021.3
enantioselective conjugate addition of carbon‐centered radicals to aliphatic and aromatic enals. The process uses an organic photoredox catalyst, which absorbs blue light to generate radicalsfrom stable precursors, in combination with a chiral amine catalyst, which secures a consistently high level of stereoselectivity. The generality of this catalytic platform is demonstrated by the stereoselective interception
electron transfer (SET) and rapid decarboxylation prior to radical–radical recombination. Importantly, decarbonylation is mitigated by this strategy. The initial computational validation on which the process is predicated matches closely with experiment. Synergising organo‐ and photocatalysis activation principles finally expands the mechanistic and synthetic scope of the classic Stetter reaction to include
Conjugate addition of benzyl copper reagents to α,α-enoates and -enones.
作者:Pieter S. Van Heerden、Barend C.B. Bezuidenhoudt、Jacobus A. Steenkamp、Daneel Ferreira
DOI:10.1016/s0040-4039(00)74218-3
日期:1992.4
Several benzylic copper reagents, BnCu(CN)MgCl, Bn2CuMgCl, BnCu-TMSCl-HMPA, and BnCu-TMSCl-TMEDA, facilitate the conjugateaddition of the benzyl ligand to α,β-enones, but only BnCu-TMSCl-TMEDA gave high yields with α,β-unsaturated esters.
Fluorinated Sulfinates as Source of Alkyl Radicals in the Photo‐Enantiocontrolled β‐Functionalization of Enals
作者:Ricardo I. Rodríguez、Marina Sicignano、José Alemán
DOI:10.1002/anie.202112632
日期:2022.2.21
use of gem-difluoro sulfinates in visible-light photocatalysis for the construction of new C−C bonds in a chiral fashion is presented. This was tackled by rerouting the chemical pathway of alkyl sulfonyl radicals from traditional sulfonylation to alkylation performance. The efficacy of these sulfinates for assisting SO2 extrusion is shown by allowing the installation of CF2-bearing scaffolds, a modern
介绍了宝石-二氟亚磺酸盐在可见光光催化中前所未有的用途,用于以手性方式构建新的 C-C 键。这是通过将烷基磺酰基自由基的化学途径从传统的磺酰化重新路由到烷基化性能来解决的。这些亚磺酸盐有助于 SO 2挤出的功效通过允许安装带有 CF 2的支架来显示,这是制药领域的一项现代任务。