1,3-Dipolar Cycloaddition of Difluoro-Substituted Azomethine Ylides. Synthesis and Transformations of 2-Fluoro-4,5-dihydropyrroles
作者:M. S. Novikov、A. F. Khlebnikov、M. V. Shevchenko、R. R. Kostikov、D. Vidovic
DOI:10.1007/s11178-005-0373-x
日期:2005.10
2-Fluoro-4,5-dihydropyrrole-3,4-dicarboxylic acid derivatives were obtained by reaction of difluorocarbene with N-substituted ketone imines in the presence of fumaronitrile, maleonitrile, or dimethyl maleate. The reaction involves intermediate formation of azomethine ylides and their subsequent cycloaddition at the double bond. 11H-Dibenz[b,e]azepine and 3,4-dihydroisoquinolines react with difluorocarbene in the presence of fumaronitrile to give fluoro-substituted dibenzo[c,f]pyrrolo[1,2-a]azepine and pyrrolo[2,1-a]-isoquinoline derivatives. Treatment of 2-fluoro-4,5-dihydropyrrole-3,4-dicarbonitrile with amines and alkoxides affords the corresponding 2-amino- and 2-alkoxy derivatives, while its reactions with hydrazine hydrate and benzimidamide lead to formation of substituted pyrrolo[2,3-c]pyrazole and pyrrolo[2,3-d]-pyrimidine derivatives.
在烟腈、马来腈或马来酸二甲酯存在下,通过二氟羰基与 N-取代酮亚胺的反应,获得了 2-氟-4,5-二氢吡咯-3,4-二羧酸衍生物。该反应涉及偶氮甲基酰化物的中间形成和随后的双键环化反应。11H- 二苯并[b,e]氮杂卓和 3,4-二氢异喹啉在富马腈存在下与二氟羰基发生反应,生成氟代二苯并[c,f]吡咯并[1,2-a]氮杂卓和吡咯并[2,1-a]异喹啉衍生物。将 2-氟-4,5-二氢吡咯-3,4-二甲腈与胺和烷氧基化合物处理,可得到相应的 2-氨基和 2-烷氧基衍生物,而与水合肼和苯并咪胺反应,可生成取代的吡咯并[2,3-c]吡唑和吡咯并[2,3-d]-嘧啶衍生物。