Synthesis of Benzoylmethylpyrazolidine Regioisomers on the Surface of Basic Adsorbents: A Competitive Attack of Crotonaldehyde at the Two Nitrogen Atoms of 1,2‐Acetylphenylhydrazine.

Abstract

Reaction of 5-hydroxypyrazolidines (I) with acetophenone on the surface of basic adsorbents affords along with the expected 5-benzoylmethyl derivative (III) its regioisomer (IV), which is formed via retro-Michael degradation of the starting compounds followed by an attack of crotonaldehyde at the imide nitrogen atom. -(SVIRIDOVA*, L. A.; GOLUBEVA, G. A.; TAVTORKIN, A. N.; Mendeleev Commun. 2005, 2, 66-67;