A Chemoselective Polarity‐Mismatched Photocatalytic C(sp<sup>3</sup>)−C(sp<sup>2</sup>) Cross‐Coupling Enabled by Synergistic Boron Activation**
作者:Jeremy Brals、Thomas M. McGuire、Allan J. B. Watson
DOI:10.1002/anie.202310462
日期:2023.10.16
We report a rare polarity-mismatched radical addition reactionusing styrene boronic acids and redox-active N-hydroxyphthalimide (NHPI) esters under photoredox catalysis. The reactiondisplays broad scope with mechanistic investigations supporting a unique synergistic activation pathway that displays chemoselectivity for styrene boronic acids in the presence of other SOMOphiles. SOMO=singly occupied
proceeds via a palladium-catalyzed [3+2] cyclization of isocyanides with alkynyl imines. In this transformation, the palladium catalyst has a triple role, serving simultaneously as a π acid, a transition-metal catalyst and a hydride ion donor, thus enabling the dual function of isocyanide both as a C1 synthon for cyanation and a C1N1 synthon for imidoylation. Significantly, the reaction is the sole successful
A trisulfur radical anion (S3.−) triggered domino thienannulation strategy for the synthesis of dibenzo[d,d′]thieno[2,3-b;4,5-b′]dithiophenes (DBTDTs) has been developed. This domino protocol is featured by no metal catalyst and the formation of six C−S and one C−C bonds in one-pot reaction. A plausible mechanism has been proposed by control experiments, intermediate trapping experiments, etc. The
开发了一种三硫自由基阴离子(S 3 .− )触发的多米诺噻吩环化策略,用于合成二苯并[ d,d' ]噻吩并[2,3- b ;4,5- b ']二噻吩(DBTDT)。该多米诺骨牌协议的特点是无需金属催化剂,在一锅反应中形成六个 C−S 和一个 C−C 键。通过控制实验、中间捕获实验等提出了一种合理的机制。DBTDT独特的不对称结构赋予其人字形堆积结构和分子间弱的S⋅⋅⋅S相互作用以及高转移积分,从而实现高载流子有机场效应晶体管的迁移率为1.52 cm 2 V -1 s -1 。