2,6-Diazasemibullvalenes: Synthesis, Structural Characterization, Reaction Chemistry, and Theoretical Analysis
作者:Shaoguang Zhang、Junnian Wei、Ming Zhan、Qian Luo、Chao Wang、Wen-Xiong Zhang、Zhenfeng Xi
DOI:10.1021/ja305581f
日期:2012.7.25
rearrangement is "frozen" in the solid state, as shown by solid-state NMR measurements and X-ray single-crystal structural analysis. Insertion of unsaturated compounds or a low-valent metal center into the NSBV C-N bond gave diverse and interesting ring-expansion products. Theoretical analysis showed that the localized structure is predominant and that the homoaromatic delocalized structure exists as a minor
通过氧化剂诱导的 CN 键形成,从 1,4-二锂硫-1,3-二烯与腈的反应中合成并分离出一系列 2,6-二氮杂半正戊烯 (NSBV)。首次确定了取代的 2,6-二氮杂半布瓦烯的活化势垒和 X 射线晶体结构。所有 NSBV 在溶液中都显示出极快的 aza-Cope 重排,但快速的 aza-Cope 重排在固态下“冻结”,如固态 NMR 测量和 X 射线单晶结构分析所示。将不饱和化合物或低价金属中心插入 NSBV CN 键中会产生多种有趣的扩环产物。理论分析表明,局部结构占主导地位,同芳香族离域结构在平衡中作为次要成分存在。