Photochemical substitution of ring hydrogen of pyridinecarboxylic esters by alkyl groups derived from solvent alcohols occurs in several paths: 1) alkylation initiated by the excited carbonyl moiety of the ester group and 2) alkylation initiated by the excitation of the π-electonic system of the pyridine ring. In the photoreaction of methyl 3-pyridinecarboxylate in acidic methanol, three types of excited
吡啶羧酸酯的环氢被衍生自溶剂醇的烷基光
化学取代发生在几种途径中:1)由酯基团的受激羰基部分引发的烷基化和 2)由
吡啶的 π-电子系统激发引发的烷基化戒指。在酸性
甲醇中
3-吡啶羧酸甲酯的光反应中,三种类型的激发态(烷基化的两个三重态和烷氧基化的单重态)同时起作用。