Unexpected formation of highly functionalized dihydropyrans via addition-cyclization reactions between dimethyl oxoglutaconate and α,β-unsaturated hydrazones
作者:Jason E. Mullins、Jean-Louis G. Etoga、Mariusz Gajewski、Joseph I. DeGraw、Charles M. Thompson
DOI:10.1016/j.tetlet.2009.02.180
日期:2009.5
The condensation between dienophiles and α,β-unsaturated hydrazone azadienes was previously reported to afford piperidines. During an attempt to adapt this reaction to the preparation of piperidine-based conformationally restricted analogs of glutamate, it was discovered that the electrophile, dimethyl oxoglutaconate (DOG) led to highly substituted dihydropyrans in 20–50% yield. The unexpected pyran