作者:Andreas Merz、Roland Schropp、Eleonore Dötterl
DOI:10.1055/s-1995-3993
日期:1995.7
A five-step general synthesis of 3,4-dialkoxypyrroles 7c-f is described starting with the condensation of dimethyl N-benzyliminodiacetate (1b) and diethyl oxalate to give dimethyl 1-benzyl-3,4-dihydroxypyrrole-2,5-dicarboxylate (2b), which is bis-O-alkylated to the corresponding 3,4-diethers 3c-g. Pyrrole N-benzyl cleavage followed by ester hydrolysis and decarboxylation leads to 7c-f in 10-50% overall yield. Pyrroles 7c-f react with formaldehyde or benzaldehydes to give meso-H- (8a-d) or meso-tetraaryloctaalkoxyporphyrins 9a-g in moderate yields.
本文描述了一种合成3,4-二烷氧基吡咯7c-f的五步通用合成方法,起始于二甲基N-苄基亚胺二乙酸酯(1b)与二乙基草酸酯的缩合反应,得到二甲基1-苄基-3,4-二羟基吡咯-2,5-二甲酸酯(2b),再通过双O-烷基化反应得到相应的3,4-二醚3c-g。随后通过吡咯N-苄基断裂、酯水解和脱羧反应,最终得到7c-f,总产率为10-50%。吡咯7c-f与甲醛或苯甲醛反应,可得到中等产率的meso-H-(8a-d)或meso-四芳基八烷氧基卟啉9a-g。