[3 + 2] Coupling of Quinone Monoacetals with Vinyl Ethers Effected by Tetrabutylammonium Triflate: Regiocontrolled Synthesis of 2-Oxygenated Dihydrobenzofurans

Tohru Kamitanaka; Yusuke Tsunoda; Yuriko Fujita; Toshifumi Dohi; Yasuyuki Kita

doi:10.1021/acs.orglett.1c02792

[3 + 2] Coupling of Quinone Monoacetals with Vinyl Ethers Effected by Tetrabutylammonium Triflate: Regiocontrolled Synthesis of 2-Oxygenated Dihydrobenzofurans

Org Lett. 2021 Dec 3;23(23):9025-9029. doi: 10.1021/acs.orglett.1c02792. Epub 2021 Nov 8.

Authors

Tohru Kamitanaka¹, Yusuke Tsunoda², Yuriko Fujita², Toshifumi Dohi^{1

2}, Yasuyuki Kita¹

Affiliations

¹ Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan.
² College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan.

PMID: 34748356
DOI: 10.1021/acs.orglett.1c02792

Abstract

The synthesis of 2-oxygenated dihydrobenzofurans involving the [3 + 2] coupling of quinone monoacetals with vinyl ethers has been realized by tetrabutylammonium triflate catalysis. The reaction involves a new activation method of the acetal moiety in quinone monoacetals under acid-free conditions affording the highly oxygenated dihydrobenzofurans. This new activation mode was achieved by using the triflate anion catalyst for stabilization of the highly reactive cationic intermediate.

Publication types

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