Coupling of arylboronic acids with benzyl halides or mesylates without adding transition metal catalysts
作者:Guojiao Wu、Shuai Xu、Yifan Deng、Chaoqiang Wu、Xia Zhao、Wenzhi Ji、Yan Zhang、Jianbo Wang
DOI:10.1016/j.tet.2016.10.031
日期:2016.12
We report herein a transition-metal-free coupling reaction of arylboronic acids with benzyl halides and mesylates for the construction of C(sp2)C(sp3) bonds. A unique feature of this coupling reaction is the formation regioisomers in some cases. Mechanistic studies suggest that this reaction may proceed via an unprecedented Friedel–Crafts-type reactionpathway under base conditions with the assistance
Efficient and selective alkylation of arenes and heteroarenes with benzyl and allyl ethers using a Ir/Sn bimetallic catalyst
作者:Susmita Podder、Sujit Roy
DOI:10.1016/j.tet.2007.06.068
日期:2007.9
A high-valent heterobimetallic catalyst namely [Ir2(COD)2(SnCl3)2(Cl)2(μ-Cl)2] (5 mol %), or dual catalyst system of [Ir(COD)Cl]2 (1 mol %) and SnCl4 (4 mol %), promotes the benzylation or allylation of arenes and heteroarenes using ethers as the alkylating agents. An electrophilic mechanism is proposed from a Hammett correlation.
An efficient in situ prepared superacid BF3–H2O promoted benzylation of arenes using benzyl alcohols and acetates achieves various diarylalkanes.
一种高效的原位制备的超强酸BF3-H2O促进的芳烃苄基化反应,使用苄醇和醋酸酯制备各种二芳基烷烃。
TBHP-promoted direct oxidation reaction of benzylic C<sub>sp3</sub>–H bonds to ketones
作者:Jiajing Tan、Tianyu Zheng、Yuqi Yu、Kun Xu
DOI:10.1039/c7ra00352h
日期:——
A metal-free oxidation system employing tert-butylhydroperoxide (TBHP) has been developed for selective oxidation of structurally diverse benzylic sp3 C–H bonds. This low-cost methodology allows for rapid generation of synthetically and biologically valued arylketones in good to excellent yields from readily available alkylarenes and diarylmethanes.
Efficient N-heterocyclic carbene nickel pincer complexes catalyzed cross coupling of benzylic ammonium salts with boronic acids
作者:Xi-Yu Liu、Hai-Bo Zhu、Ya-Jing Shen、Jian Jiang、Tao Tu
DOI:10.1016/j.cclet.2016.09.006
日期:2017.2
Abstract Pyridine-bridgedbis-benzimidazolylidene nickel complexes exhibited very high catalytic activity toward cross coupling of inactive (hetero)aryl benzylic ammonium salts with (hetero)aryl and alkenyl boronic acids under mild reaction conditions. Even at 2 mol% catalyst loading, a wide range of substrates for both coupling partners with different steric and electronic properties were well tolerated