Insight into the Willgerodt-Kindler Reaction ofω-Haloacetophenone Derivatives: Mechanistic Implication

摘要

This paper reports efforts aimed at tuning up the synthesis of a compound library centered on the general template 2-amino-1-phenyl-2-thioxoethanone taking the condensation ofω-haloacetophenone, octasulfur, and morpholine as pilot reaction. Considerations about atomic economy were found extremely precious in selecting the best starting halo-reagent. A one-pot practical method based on use of 2-bromo-1-phenylethanone as substrate andN,N-dimethylformamide as solvent can be easily scaled up to gram amounts (72% yield). Based on this synthetic approach, some more specific examples are reported.