Synthesis of N,N’-Linked Isothiazolium Salts via Intramolecular Cyclocondensation of Hydrazonium Salts

Abstract

Interaction of β -thiocyanatovinyl aldehydes with N-amino heterocycles leads to formation of α, β -unsaturated hydrazonium salts dependent on the functional surroundings. The latter can undergo further intramolecular cyclocondensation giving rise to N, N -linked isothiazolium salts as the final product. The isolated hydrazonium salts, not undergoing ring formation, have s-trans conformation of the azadiene system.

Synthesis of N,N′-Linked Bisazaheterocycles with Sulfonamide Structure via Oxidation of S,N-Heteroaromatic Cations

“…Compared to the 13 C NMR data of 12, 16 the main diagnostic signals of the salts 10a,b, 11a,c were shifted to lower field. This can serve as further evidence for the difference in electrophilicity of the salts 12 and their acceptor substituted analogues 10, 11, and explain the reduced reactivity of 12 with nucleophilic reagents H 2 O 2 and MMPP.…”

N,N′-Linked 1,2-benzisothiazol-3(2H)-one 1,1-dioxides: synthesis, biological activity, and derived radicals

“…Cyclization products 4 were not obtained (Scheme 1). 12 One of the described methods for the preparation of benzoannelated isothiazole 1,1-dioxides is based on the reaction of 2-chlorosulfonylbenzoyl chloride with anilines. 13 We applied this approach, and the synthesis of N,N 0 -linked saccharin derivatives was conducted by means of tandem acylation/sulfonylation reaction of N-amino compounds with 2-chlorosulfonylbenzoyl chloride 6.…”