Study of the transmetallation of silicon derivatives ofo-carboranes on treatment with BunLi
摘要:
Silyl-substituted o-carboranes 1-R-2-Me3Si(CH2)(n)-1,2-C2B10H10 (R = Me, Ph; n = 0, 1) undergo transmetallation on treatment with (BuLi)-Li-n to form lithium derivatives of o-carboranes, 1-R-2-Li(CH2)(n)-1,2-C2B10H10, where n = 0, 1. A silicon derivative of o-carborane, 1-Ph-2-(Me3SiCHPh)-1,2-C2B10H10, undergoes neither transmetallation nor metallation at the benzyl CH-group on treatment with (BuLi)-Li-n due to significant steric hindrance.
Iridium(III)-Catalyzed Selective Sulfonamidation of<i>o</i>-Carborane with Sulfonyl Azide by Carboxylic Acid-Assisted B(4)-H Bond Activation
作者:Huanhuan Li、Fan Bai、Hong Yan、Changsheng Lu、Vladimir I. Bregadze
DOI:10.1002/ejoc.201601537
日期:2017.3.10
An IrIII‐catalyzed direct cage B(4)–H bond sulfonamidation with carboxylic acid assistance is reported. This reaction proceeds in the absence of both external oxidants and ligands, and shows high yields and good functional group tolerance. In particular, direct cage B(4)–H bond amination was achieved by using aryl and aliphatic azides as nitrenoid sources for the first time.
Palladium-catalyzed regioselective synthesis of B(4,5)- or B(4)-substituted <i>o</i>-carboranes containing α,β-unsaturated carbonyls
作者:Chuyi Zhang、Qian Wang、Song Tian、Jianwei Zhang、Jiaoyi Li、Ling Zhou、Jian Lu
DOI:10.1039/d0ob00698j
日期:——
With the help of a carboxylic acid directing group, Pd-catalyzed regioselective synthesis of B(4,5)- or B(4)-substituted o-carboranes containingα,β-unsaturated carbonyls has been reported. The –COOH, removed during the course of the reaction, is responsible for controlling the regioselectivity. The desired products could be obtained in moderate to good yields.
8-Aminoquinoline as a bidentate traceless directing group for Cu-catalyzed selective B(4,5)–H disulfenylation of <i>o</i>-carboranes
作者:Yu Chen、Yangjian Quan、Zuowei Xie
DOI:10.1039/d0cc05207h
日期:——
A traceless bidentate directing group guided copper catalyzed cage B(4,5)–H disulfenylation of o-carboranes has been achieved, where the in situ departure of 8-aminoquinoline circumvents additional process for directing group removal.
Iridium-Catalyzed Cyclative Indenylation and Dienylation through Sequential B(4)–C Bond Formation, Cyclization, and Elimination from <i>o</i>-Carboranes and Propargyl Alcohols
作者:Yonghyeon Baek、Kiun Cheong、Gi Hoon Ko、Gi Uk Han、Sang Hoon Han、Dongwook Kim、Kooyeon Lee、Phil Ho Lee
DOI:10.1021/jacs.0c02121
日期:2020.6.3
indenylation through sequential B(4)-C and intramolecular C-C bond formation from o-carboranes and propargyl alcohols, leading to the formation of B(4)-indenylated-o-carboranes with excellent regioselectivity via direct B-H activation. Moreover, the iridium-catalyzed regioselective 1,3-dienylation has been accessed through sequential B-H activation, dehydration, and decarboxylation, producing B(4)-dienylated-o-carboranes
Iridium-Catalyzed Selective B(4)–H Acylmethylation of <i>o</i>-Carboranes with Sulfoxonium Ylides
作者:Lin-Bao Zhang、Zuowei Xie
DOI:10.1021/acs.orglett.1c04335
日期:2022.2.18
A highly efficient Ir-catalyzed regioselective cage B(4)–H acylmethylation of o-carboranyl acids using sulfoxonium ylides as alkylating regents has been developed, leading to the preparation of a large class of B(4)-acylmethylated o-carboranes in good to excellent yields with a broad substrate scope under redox neutral conditions. The -COOH moiety serves as the traceless directing group and controls
已开发出一种高效的 Ir 催化区域选择性笼 B(4)-H 酰基甲基化邻碳硼烷酸,使用氧化鎓叶立德作为烷基化试剂,从而制备了一大类 B(4)-酰基甲基化邻碳硼烷。在氧化还原中性条件下以广泛的底物范围获得优异的产量。-COOH 部分用作无痕导向基团并控制区域选择性和单选择性。