An efficient metal-free cascade process for the synthesis of 4-arylpyrimido[1,2-b]indazole-3-carbonitrile derivatives
摘要:
An efficient metal-free cascade reaction to synthesize novel pyrimido[1,2-b]indazole-3-carbonitrile derivatives was reported. The reaction starts from aromatic aldehydes, 1H-indazol-3-amine (4-chloro-1Hindazol-3-amine), and 3-(1H-indol-3-yl)-3-oxopropanenitrile or 3-oxo-3-arylpro-panenitrile in the presence of ethanol and triethylamine under plain laboratory conditions. The reaction was easy to operate with good tolerance to substrates in high yield. (C) 2017 Elsevier Ltd. All rights reserved.