通过采用钯催化的 Suzuki 偶联反应和钯催化的乙酰化反应,以及四氯化硅介导的三聚反应,合成了一系列包含三到六个邻碳硼烷簇的 C(3)-对称 pi 共轭化合物。发现含有碳硼烷的延伸三聚体发出蓝光。将邻碳硼烷簇并入扩展的 pi 共轭系统导致其相对荧光量子产率提高 22-70%。邻碳硼烷簇的斩首使这些扩展的三聚体可溶于水,并且还发现它们的水溶液具有荧光,但荧光强度降低。发现附加碳硼烷的 pi 共轭化合物具有极强的热稳定性,
通过采用钯催化的 Suzuki 偶联反应和钯催化的乙酰化反应,以及四氯化硅介导的三聚反应,合成了一系列包含三到六个邻碳硼烷簇的 C(3)-对称 pi 共轭化合物。发现含有碳硼烷的延伸三聚体发出蓝光。将邻碳硼烷簇并入扩展的 pi 共轭系统导致其相对荧光量子产率提高 22-70%。邻碳硼烷簇的斩首使这些扩展的三聚体可溶于水,并且还发现它们的水溶液具有荧光,但荧光强度降低。发现附加碳硼烷的 pi 共轭化合物具有极强的热稳定性,
Copper-catalyzed cross-coupling of 1-haloalkyl -o- carboranes with Grignard reagents: an efficient route to monosubstituted o- carborane derivatives
作者:Ju-You Lu、Yongmei Du、Bo Zhao、Jian Lu
DOI:10.1016/j.tet.2015.11.019
日期:2016.1
A convenient and efficient copper-catalyzed reaction has been developed for the synthesis of functionalized o-carborane derivatives by using a Cu/phosphine catalytic system. Cross-coupling of readily available 1-haloalkyl-o-carboranes with Grignard reagents proceeds efficiently under mild conditions, and the corresponding monosubstituted o-carboranes were obtained in good to excellent yields. (C) 2015 Elsevier Ltd. All rights reserved.
A kinetic study of ortho-carborane formation focusing on the reaction of various decaborane adducts [B10H12L2; L=Me2S, Ph2S, tert-Bu2S, (C6F5)(2)S, MeSPh, MeSC6F5, MeS(sec-Bu)] with three acetylenes (propargyl bromide, 2-butyne-1,4-diacetate, 1-nonyne) has been carried out. For a given acetylene, the rate constants decrease with both an increase in the electronegativity and/or an increase in size of substituents on sulfur. Yields of orthocarborane have been shown to increase as the size and/or basicity of the Lewis base increases and, for a given adduct, with the lower basicity of the acetylene.