Reaction of ethyl 2-(arylidene)acetoacetates, 3-methyl-1H-pyrazol-5(4H)-one, and ammonium acetate: Unexpected formation of bis(pyrazolyl)methanes versus fused pyrazolo-1,4-dihydropyridines
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引用次数: 0
Abstract
The reaction of 3-methyl-1H-pyrazol-5(4H)-one, ethyl 2-(arylidene)acetoacetates, and ammonium acetate in refluxing ethanol leads to the formation of 4,4′-(arylmethylene)bis(3-methyl-1H-pyrazolyl-5-ol) derivatives with high yields, instead of the expected fused pyrazolo-1,4-dihydropyridines. This suggests the presence of a reactive vinylogous imino derivative as an intermediate.
期刊介绍:
Synthetic Communications presents communications describing new methods, reagents, and other synthetic work pertaining to organic chemistry with sufficient experimental detail to permit reported reactions to be repeated by a chemist reasonably skilled in the art. In addition, the Journal features short, focused review articles discussing topics within its remit of synthetic organic chemistry.