1310552-56-7Relevant academic research and scientific papers
A one-pot, non-catalytic approach to 1,2,4-benzothiadiazine-1,1-dioxides
Cherepakha, Artem,Kovtunenko, Vladimir O.,Tolmachev, Andrey,Lukin, Oleg
experimental part, p. 6233 - 6239 (2011/09/19)
Condensations of o-halo-substituted benzenesulfonyl chlorides with 2-aminopyridines and amidines may give the corresponding 1,2,4-benzothiadiazine- 1,1-dioxides under mild, non-catalytic conditions in nearly quantitative yields. The successful one-pot cyclization depends on three factors: (i) the nature of the o-halogen, (ii) the electronic character of the benzene ring substituent, and (iii) the steric load around the amidine unit. O-Fluorobenzenesulfonyl chlorides bearing methylcarboxyl- or nitro-group and o-chloro- and o-bromobenzenesulfonyl chlorides bearing nitro-group are reactive enough to give the desired 1,2,4-benzothiadiazine-1,1-dioxides in a one-pot base-promoted reaction. In all other cases, open-chain sulfonylated amidine intermediates are isolated. The latter are converted to the title compounds either in the presence of potassium carbonate or upon the addition of a copper(I) catalyst.
Facile synthesis of 4H-1,2,4-benzothiadiazine-1,1-dioxides
Cherepakha, Artem,Kovtunenko, Vladimir O.,Tolmachev, Andrey,Lukin, Oleg,Nazarenko, Konstantin G.
experimental part, p. 1977 - 1989 (2011/06/23)
o-Bromoarylsulfonylated amidines prepared either by acylation of amidine with o-bromoarylsulfonyl chloride or through the reaction of o-bromoarylsulfoamide with lactime ether underwent Cu(I)-catalyzed intramolecular cyclization to give 4H-1,2,4-benzothiadiazine-1,1-dioxides in good yield. By varying substituents on arylsulfonyl moieties, amidines, and lactime ethers, a small library of structurally diverse 4H-1,2,4- benzothiadiazine-1,1-dioxide derivatives was prepared.
