Reaction of dicyanomethylides with 3-(3′,3′-dimethyltriazene-1-yl)- pyridine-4-carboxylic acid. Unexpected preferential formation of pyrido[4,3-a]indolizines
作者:Kiyoshi Matsumoto、Takane Uchida、Mituo Toda、Kinuyo Aoyama、Akikazu Kakehi、Atsushi Shigihara、J.William Lown
DOI:10.1016/0040-4039(93)88005-4
日期:1992.12
Contrary to theoretical predictions on the basis of a discrete hetaryne intermediate (frontier orbitals, total atomic charges on C-3 and C-4, and activation energies for the concerted process) from the MO calculations, reactions of dicyanomethylides with 3-(3′,3′-dimethyltriazene-1-yl)pyridine-4-carboxylic acid, a formal precursor of 3,4-didehydropyridine, afforded exclusively the pyrido[4,3-a]indolizines
根据MO计算,二氰甲基化物与3-(3'的反应),基于离散的戊炔中间体(前沿轨道,C-3和C-4上的总原子电荷以及协同过程的活化能)的理论预测与之相反。 3,4-二氢吡啶的正式前体,3′-二甲基三氮烯-1-基)吡啶-4-羧酸仅提供吡啶并[4,3-a]吲哚并二氮杂zi。结果与涉及两性离子戊炔前体的机理更好。