1-Methylimidazole-catalyzed reaction between tosylmethyl isocyanide and dialkyl acetylenedicarboxylates:An efficient synthesis of functionalized pyrroles

An efficient 1-methylimidazole-catalyzed synthesis of dialkyl 2-[（4-methylphenyl）sulfonyl]-1H-pyrrole-3,4-dicarboxylates is described.The reactive 1：1 zwitterionic intermediate formed by the addition of 1-methylimidazole to dialkyl acetylenedicarboxylates is trapped by tosylmethyl isocyanide（TOSMIC） to afford the title compounds in excellent yields.

对甲苯磺酰甲基异腈的合成研究

研究了对甲苯磺酰甲基甲酰胺脱水合成对甲苯磺酰甲基异腈,考察了溶剂种类和用量、原料配比、反应时间等因素对反应结果的影响,得到了最佳反应条件,即m(对甲苯磺酰甲基甲酰胺)=6g,V(二氯甲烷)=30mL,n(酰胺)∶n(三乙胺)∶n(三氯氧磷)=1∶5∶1.1,反应温度为-5℃,滴加时间为20min,反应时间为60min,沉降时间为60min。在上述条件下,对甲苯磺酰甲基异腈的收率和纯度分别为83.3%和98.0%。其结构经FT-IR和NMR分析确证。