Doubly hydrogen-bridged 1,2-diphenylenediboranes derived from 9-chloro-9-borafluorene and ligand exchange reactions
作者:H. Hong、T.C. Chung
DOI:10.1016/j.jorganchem.2003.09.027
日期:2004.1
Cyclic 1,2-diphenylenediboranes containing a doubly hydrogen-bridged structure, including 1,2-(2,2′biphenylylene)diborane(I) and 1,2-(2,2′biphenylylene)-1,2-diethyldiborane (II), are conveniently prepared by treating 9-chloro-9-borafluorene with NaBH4 and Na(Et)3BH, respectively. The reaction mechanism involves an initial Cl–H exchange to form 9-borafluorene containing a reactive 5-member ring diarylborane
包含双氢桥联结构的环状1,2-二苯二氢呋喃酮,包括1,2-(2,2 '联苯撑)乙硼烷(I)和1,2-(2,2 '联苯撑)-1,2-二乙基二硼烷(II )分别通过分别用NaBH 4和Na(Et)3 BH处理9-氯-9-硼芴方便地制备。反应机理涉及最初的Cl-H交换以形成含有反应性5元环二芳基硼烷部分的9-硼芴,其随后与在原位形成的含有B-H的残基(BH 3或HBEt 2)以产生环状1,2-二苯二甲硼烷化合物。双氢桥结构在高达50°C的温度下显示出良好的热稳定性。在较高温度下热裂解后,所有游离的B-H基团都变得非常活泼,包括与α-烯烃的硼氢化反应。复杂化研究还表明,该乙内硼烷部分与强碱(例如吡啶)形成1:2的复合物。