Acid-mediated ring-expansion reaction of N-aryl-2-vinylazetidines: synthesis and unanticipated reactivity of tetrahydrobenzazocines

Tomoaki Shimizu; Shunsuke Koya; Ryu Yamasaki; Yuichiro Mutoh; Isao Azumaya; Kosuke Katagiri; Shinichi Saito

doi:10.1021/jo500249c

Acid-mediated ring-expansion reaction of N-aryl-2-vinylazetidines: synthesis and unanticipated reactivity of tetrahydrobenzazocines

J Org Chem. 2014 May 16;79(10):4367-77. doi: 10.1021/jo500249c. Epub 2014 Apr 28.

Authors

Tomoaki Shimizu¹, Shunsuke Koya, Ryu Yamasaki, Yuichiro Mutoh, Isao Azumaya, Kosuke Katagiri, Shinichi Saito

Affiliation

¹ Department of Chemistry, Faculty of Science, Tokyo University of Science , Kagurazaka, Shinjuku, Tokyo 162-8601, Japan.

PMID: 24731245
DOI: 10.1021/jo500249c

Abstract

The aza-Clasen rearrangement of N-aryl-2-vinylazetidines has been explored. N-Aryl-2-vinylazetidines were transformed to corresponding tetrahydrobenzazocines in good yields. Unexpectedly, the tetrahydrobenzazocine was unstable and readily isomerized to vinyltetrahydroquinoline in the presence of acid. The mechanism of this ring contraction was studied in detail.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Catalysis
Cyclazocine / analogs & derivatives*
Cyclazocine / chemical synthesis*
Isomerism
Molecular Structure
Quinolines / chemistry*
Vinyl Compounds / chemistry*

Substances

Quinolines
Vinyl Compounds
Cyclazocine