Synthesis of novel 2-phenyl-5-substituted dihydropyrimidines using 2-phenyl-1,3-diaza-1,3-butadienes and electron-deficient olefins
作者:Yoshio Nishimura、Yoshizumi Yasui、Satoshi Kobayashi、Masahiko Yamaguchi、Hidetsura Cho
DOI:10.1016/j.tet.2012.02.064
日期:2012.4
A novel synthetic method for 2,5-disubstituted dihydropyrimidines was developed. The cyclization of 1,3-diaza-4-dimethylamino-1,3-butadienes having a N-protecting group (N-Boc, N-Cbz, N-n-C4H9, N-Bn or N-Ph) with electron-deficient olefins, such as α,β-unsaturated carbonyl compounds, phenyl vinyl sulfone, and acrylonitrile was studied in detail. The cyclization smoothly proceeded to afford 4-dimethylamino-1
开发了2,5-二取代的二氢嘧啶的新型合成方法。具有N-保护基(N -Boc,N -Cbz,N - n -C 4 H 9,N -Bn或N-Ph)与缺电子的烯烃,如α,β-不饱和羰基化合物,苯基乙烯基砜和丙烯腈进行了详细的研究。顺利进行环化,以高收率得到4-二甲基氨基-1,4,5,6-四氢嘧啶或1,6-二氢嘧啶。通过β-消除二甲基氨基,将分离的4-二甲基氨基-1,4,5,6-四氢嘧啶转化为2,5-二取代的1,6-二氢嘧啶。2,5-二取代的-1,4-除去的后获得(6)-dihydropyrimidines ñ -Boc或ñ -Cbz基。观察到所得二氢嘧啶的独立互变异构体。