BF3-Catalyzed Skeletal Rearrangement of 7-En-2-ynones to endo-Type Cyclic Dienes

Daisuke Sato; Yuichiro Watanabe; Keiichi Noguchi; Junichiro Kanazawa; Kazunori Miyamoto; Masanobu Uchiyama; Akio Saito

doi:10.1021/acs.orglett.0c00949

BF₃-Catalyzed Skeletal Rearrangement of 7-En-2-ynones to endo-Type Cyclic Dienes

Org Lett. 2020 Jun 5;22(11):4063-4067. doi: 10.1021/acs.orglett.0c00949. Epub 2020 Apr 7.

Authors

Daisuke Sato¹, Yuichiro Watanabe², Keiichi Noguchi³, Junichiro Kanazawa², Kazunori Miyamoto², Masanobu Uchiyama^{2

4}, Akio Saito¹

Affiliations

¹ Division of Applied Chemistry, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan.
² Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
³ Instrumentation Analysis Center, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan.
⁴ Cluster for Pioneering Research (CPR), RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.

PMID: 32255350
DOI: 10.1021/acs.orglett.0c00949

Abstract

Transition-metal-catalyzed cycloisomerization reactions with skeletal rearrangement of 1,n-enynes to afford cyclic dienes (particularly exo-cyclization products) have been well studied. However, there are few reports on the nonmetal-catalyzed skeletal rearrangement of enynes and skeletal rearrangement of electron-deficient enynes such as n-en-2-ynones. Here, we describe BF₃·MeCN-catalyzed synthesis of 3-alkylidenecyclohexenes from 7-en-2-ynones, representing the first nonmetal-catalyzed skeletal rearrangement of 1,6-enynes to endo-type cyclic dienes.

Publication types

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