1.
J Org Chem
; 85(19): 12058-12066, 2020 Oct 02.
Artigo
em Inglês
| MEDLINE
| ID: mdl-32883078
RESUMO
[2,1]Benzothiazine S,S-dioxides 2 were synthesized by simply heating o-nitrostyrenes with elemental sulfur in 3-picoline with complete atom economy. This reaction was found to occur without any added catalyst and consist of a cascade of reduction of the nitro group, sulfuration of a C-H of the double bond, oxidation of a sulfur atom to its highest oxidation state by the migration of two oxygen atoms from the nitro group, and formation of new N-S bonds. Furthermore, the method could also be applied to o-nitrocinnamamides and cinnamate esters.