Copper-catalyzed cascade reaction of 4-iodopyrazole derivatives with amidines for the synthesis of pyrazolo[4,3-d]pyrimidine derivatives

摘要

An efficient copper-catalyzed cascade reaction of 4- iodopyrazolecarbaldehydes and 4-iodopyrazolecarboxamides with substituted amidines for the preparation of substituted pyrazolo[4,3-d]pyrimidines and pyrazolo[4,3-d]pyrimidin-7(6H)-ones, respectively, is described. A copper-mediated, one-step synthesis of substituted pyrazolo[4,3-d]pyrimidines and pyrazolo[4,3-d]pyrimidin-7(6H)-ones by reaction between 4-iodopyrazole derivatives and substituted amidines is reported.