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

Shi-Heng Hung; Yu-Min Wang; Yi-Hung Liu; Shiuh-Tzung Liu

doi:10.1021/acs.joc.4c01152

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

J Org Chem. 2024 Sep 6;89(17):12762-12768. doi: 10.1021/acs.joc.4c01152. Epub 2024 Aug 23.

Authors

Shi-Heng Hung¹, Yu-Min Wang¹, Yi-Hung Liu¹, Shiuh-Tzung Liu¹

Affiliation

¹ Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.

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.