Transformation of N-(5-Acetyl-6-methyl-2-oxo-2H-pyran-6-yl)benzamide with hydrazines in the presence of an acidic catalyst

摘要

2H-Pyran-2-one derivative (1) was transformed with heterocyclic hydrazines and 2,4-dinitrophenylhydrazine,under the inlfuence of various acidic catalysts,into N-[5-(1-hydrazonoethyl)-6-methyl-2-oxo-2H-pyran-3-yl]benzamides (3) as the main products,accompanied in some cases by the corresponding (E)-alpha,beta-didehydro-alpha-amino acid derivatives (4).