Construction of cyclopenta[b]pyran-2-ones via chemoselective (3 + 2) cycloaddition between 2-pyrones and vinyl cyclopropanes. Issue 6 (24th February 2020)

• Record Type: Journal Article
• Authors: Liang, Xuefeng; Ye, Weijian; Thor, Waygen; Sun, Lantian; Wang, Bo; He, Shuzhong; Cheng, Yuen-Kit; Lee, Chi-Sing
• Is Part Of: Organic chemistry frontiers. Volume 7:Issue 6(2020)
• Page Start: 840
• Page End: 845
• Publication Date: 2020-02-24
• Subjects: Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1039/d0qo00049c
• Languages: English
• ISSNs: 2052-4110

Abstract

Abstract : A chemoselective (3 + 2) cycloaddition of 2-pyrones and vinyl cyclopropanes for efficient and diastereoselective synthesis of cyclopenta[ b ]pyran-2-ones. Abstract : A method for synthesising cyclopenta[ b ]pyran-2-ones through direct (3 + 2) cycloaddition between 2-pyrones and vinyl cyclopropanes is described. In the presence of Pd2 (dba)3 /dppe in toluene, a series of 2-pyrones undergo chemoselective (3 + 2) cycloaddition with vinyl cyclopropanes and afford cyclopenta[ b ]pyran-2-ones in high yields (78–96%). The trans / cis ratio of the cycloadducts has been optimised up to 10 : 1. The proposed mechanism of this cycloaddition has been rationalised by computational studies.