SOCl2-Catalyzed Meyer-Schuster Rearrangement of 3°-Propargylic Alcohols: Synthesis of Densely Arene-Substituted Pyrazolines Bearing Quaternary Centers from α,β-Unsaturated Carbonyl Compounds and Arylhydrazines

Meyer-Schuster rearrangement of 3 degrees- propargyl alcohol to the corresponding alpha,ss-unsaturated carbonyl compounds under SOCl2 catalysis has been reported. Terminal and internal propargyl alcohols efficiently participated in the reaction. Furthermore, we have demonstrated the synthetic utility of conjugated carbonyl compounds to access densely arenesubstituted pyrazolines bearing quaternary centers by reacting with arylhydrazine hydrochloride. Isotopic labeling studies were carried out to gain insights into the reaction mechanism.

Automated summary

The Meyer-Schuster rearrangement and its synthetic application have been reported in this study. This reaction efficiently converts 3 degrees-propargyl alcohol to α,β-unsaturated carbonyl compounds, and can be used for the synthesis of densely arene-substituted pyrazolines bearing quaternary centers through reaction with arylhydrazine hydrochloride.