Preparation of 4-Allenyloxazolines from (Z)-2-En-4-yn-1-ol via Propargyl/Allenyl Isomerization.

ABSTRACT

A novel method for the preparation of 4-allenyl-oxazolines 2 is described via the reaction of 2-en-4-yn-1-ols 1 with trichloroacetonitrile in the presence of DBU. Reaction proceeds through the nucleophilic attack of OH functionality in 1 to CCl3CN followed by cyclization, propargyl/allene isomerization, and protonation. In this investigation, it is noticed that propargyl/allene isomerization is sensitive to the substituents.