The Acid and/or Thermal Mediated Ring Contraction of 4H-1,2,6-Thiadiazines To Afford 1,2,5-Thiadiazoles

Org Lett. 2016 Aug 19;18(16):4056-9. doi: 10.1021/acs.orglett.6b01929. Epub 2016 Aug 2.

Abstract

A near-quantitative acid and/or thermal mediated ring contraction of 3',5'-diarylspiro(benzo[d][1,3]dioxole-2,4'-[1,2,6]thiadiazines) affords 3-aryl-4-(2-arylbenzo[d][1,3]dioxol-2-yl)-1,2,5-thiadiazoles. The reaction scope was studied providing 11 examples of this ring contraction. A double Wagner-Meerwein reaction mechanism is proposed.

Publication types

  • Research Support, Non-U.S. Gov't