Five-membered heterocycles. Part II. Crystal structures and HOMA index calculations for selected 1,3,4-thiadiazole derivatives
作者:A. Mrozek、J. Karolak-Wojciechowska、P. Amiel、J. Barbe
DOI:10.1016/s0022-2860(99)00460-3
日期:2000.6
Abstract Crystal structures of four bisubstituted 1,3,4-thiadiazole derivatives were determined. Detailed description of the five-membered heteroring geometry is enabled thorough analysis of ring aromaticity. For this purpose the HOMA index was used as a quantitative measure of aromaticity. The calculated HOMA indices evidenced the role of substituents. In particular, increase in the substituent electrophilicity
摘要 确定了四种双取代的 1,3,4-噻二唑衍生物的晶体结构。五元杂环几何结构的详细描述使得能够对环芳香性进行彻底分析。为此,使用 HOMA 指数作为芳香性的定量测量。计算的 HOMA 指数证明了取代基的作用。特别是,取代基亲电性的增加导致芳香性的增加。