Tertiary amine-catalyzed (4 + 2) annulations of δ-acetoxy allenoates: synthesis of multisubstituted 4H-pyran and 4H-chromene

Yiting Gu; Falin Li; Pengfei Hu; Daohua Liao; Xiaofeng Tong

doi:10.1021/acs.orglett.5b00359

Tertiary amine-catalyzed (4 + 2) annulations of δ-acetoxy allenoates: synthesis of multisubstituted 4H-pyran and 4H-chromene

Org Lett. 2015 Mar 6;17(5):1106-9. doi: 10.1021/acs.orglett.5b00359. Epub 2015 Feb 18.

Authors

Yiting Gu¹, Falin Li, Pengfei Hu, Daohua Liao, Xiaofeng Tong

Affiliation

¹ Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology , Shanghai 200237, China.

PMID: 25692476
DOI: 10.1021/acs.orglett.5b00359

Abstract

The DABCO-catalyzed divergent (4 + 2) annulations of δ-acetoxy allenoates 1 are reported. The chemical behavior of 1 under DABCO catalyst was found to be substrate dependent. Allenoate 1 with an aromatic group at δC preferentially reacted with salicylaldehyde derivative 2, delivering 4H-chromenes 3. On the other hand, allenoates 1 with an alkyl group at δC readily underwent (4 + 2) annulations with oxo diene 4 to afford 4H-pyrans 5.

Publication types

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