New Synthesis and Reactions of Ethyl 5-amino-4-cyano-1-phenyl-1<i>H</i>-pyrazole-3-carboxylate
作者:Sachin A. Gangurde、Shrikant B. Kanawade、Prashant S. Nikam、Dinesh C. Bhavsar、Raghunath B. Toche
DOI:10.1002/jhet.1691
日期:2014.7
Synthesis of ethyl 5‐amino‐4‐cyano‐1‐phenyl‐1H‐pyrazole‐3‐carboxylate 5 has been achieved via abnormal Beckmann rearrangement of o‐chloroaldehyde 1. Reaction of o‐aminocarbonitrile 5 with concentrated H2SO4 furnished expected o‐aminocarboxamide pyrazole 6. Key intermediates o‐aminocarbonitrile 5 and o‐aminocarboxamide 6 were successfully utilized for the synthesis of pyrazolopyrimidine derivatives
合成5-氨基-4-氰基-1-苯基-1- ħ吡唑-3-甲酸乙酯5已经通过的异常贝克曼重排实现ö -chloroaldehyde 1。的反应ø -aminocarbonitrile 5与浓硫酸2 SO 4家具的预期ö -aminocarboxamide吡唑6。关键中间体邻氨基甲腈5和邻氨基羧酰胺6被成功地用于合成吡唑并嘧啶衍生物。邻氯乙腈中Cl的替代3与仲胺一起提供了新的合成子13,该合成子进一步用于合成多取代的杂环。所获得的新产物通过IR,1 H和13 C NMR以及质谱进行了很好的表征。