Studies on selective preparation of aromatic compounds. 20. Selective preparation of 2-mono- and 2,2'-disubstituted biphenyl using the tert-butyl group as a positional protective group
Rhodium-Catalyzed Intramolecular C−H Silylation by Silacyclobutanes
作者:Qing-Wei Zhang、Kun An、Li-Chuan Liu、Shuangxi Guo、Chenran Jiang、Huifang Guo、Wei He
DOI:10.1002/anie.201602376
日期:2016.5.17
Silacyclobutane was discovered to be an efficient C−H bond silylation reagent. Under the catalysis of RhI/TMS‐segphos, silacyclobutane undergoes sequential C−Si/C−H bond activations, affording a series of π‐conjugated siloles in high yields and regioselectivities. The catalytic cycle was proposed to involve a rarely documented endocyclic β‐hydride elimination of five‐membered metallacycles, which after
发现硅环丁烷是一种有效的CH键甲硅烷基化试剂。在Rh I / TMS-segphos的催化下,硅环丁烷经历了连续的C-Si / C-H键活化,从而以高收率和区域选择性提供了一系列π-共轭硅化物。有人提出催化循环涉及很少有文献记载的五元金属环的环内β-氢化物消除,在还原性消除后会产生能够进行CH活化的Si-Rh I物种。
Chiral NHC/Cu(I)-Catalyzed Asymmetric Hydroboration of Aldimines: Enantioselective Synthesis of α-Amido Boronic Esters
Non-C-2-symmetric (N-alkyl, N-aryl)-hybrid chiral NHC/Cu(I) complexcatalyzedasymmetric hydroboration of N-benzoyl aldimines has been developed. The reaction proceeded smoothly at room temperature, giving alpha-amido boronic esters in excellent yields (u
with antiaromatic character has been utilized to synthesize a double aza[7]helicene with rarely accessible chiroptical properties in the red region as well as redox-active behaviour. This chiral polyaromatic hydrocarbon system shows oxidation-state-dependent aromaticity/antiaromaticity switching via oxidation-induced cation species.
as a universal heteroatom-doped chiral scaffold. The respective reactions of electron-donating 1 with a triarylborane acceptor via palladium-catalyzedBuchwald–Hartwig C–N coupling and with the open-shell doublet-state TTM radical via nucleophilic aromatic substitution (SN2Ar) resulted not only in tunable emissions from blue to the NIR domain but also in significantly enhanced emission quantum efficiency
本文提出了新的手性发光分子(N7-BMes2和N7-TTM),使用构型稳定的氮杂[7]螺烯 ( 1 ) 作为通用的杂原子掺杂手性支架。给电子1与三芳基硼烷受体通过钯催化的 Buchwald-Hartwig C-N 偶联反应以及通过亲核芳香取代 (S N 2Ar) 与开壳双态 TTM 自由基的反应不仅产生了可调节的发射蓝色到近红外域的同时还显着提高了发射量子效率高达 Φ = 50%。
[EN] SPIROBIFLUORENE ORGANIC LIGHT-EMITTING COMPOUND AND ORGANIC LIGHT-EMITTING DEVICE<br/>[FR] COMPOSÉ ÉLECTROLUMINESCENT ORGANIQUE À BASE DE SPIROBIFLUORÈNE ET DISPOSITIF ÉLECTROLUMINESCENT ORGANIQUE<br/>[ZH] 一种螺二芴类有机电致发光化合物及有机电致发光器件