Attempted generation of substituted 1,2,3-triazolium-1-methanides: a new ring expansion to 2,3-dihydro-1,2,4-triazines: ab initio calculations on 1,2,3-triazolium-1-oxide, -1-imide, and -1-methanide 1,3-dipoles and a striking illustration of the Hammond principle in the cyclisation of hetero-1,3,5-trienes
作者:Richard N. Butler、J. Paul Duffy、D. Cunningham、P. McArdle、Luke A. Burke
DOI:10.1039/c39900000882
日期:——
Treatment of 1-methyl-1,2,3-triazolium salts with ethoxide gave 2,3-dihydro-1,2,4-triazines via 1,2,5-triazahexa-1,3,5-trienes but the expected 1,2,3-triazolium-1-methanide 1,3-dipoles were not detected and ab initio calculations suggest that they are thermodynamically unfavoured; the X-ray crystal structure of (6a), a dihydro-1,2,4-triazine, is reported.
用乙醇处理1-甲基-1,2,3-三唑鎓盐可通过1,2,5-三氮杂六-1,3,5-三烯得到2,3-二氢-1,2,4-三嗪,但预期的1未检测到1,2,3-三唑-1-甲酰1,3-偶极子,并且从头算计算表明它们在热力学上不利。报道了(6a)的二氢-1,2,4-三嗪的X射线晶体结构。