Synthesis of 2-(2-alkoxycarbonylphenylthio)-1,2-benzisothiazolin-3-ones from 2-sulfenamoylbenzoates

The mechanism of formation of 2-(2-alkoxycarbonylphenyl-thio)-1,2-benzisothiazolin-3-ones, which were obtained by the heating of 2-sulfenamoylbenzoates, was investigated. It appears that transamination occurred on the sulfur atom of a 2-sulfenamoylbenzoate between the amino group and the 1,2-benzisothiazolin-3-one, which formed by the cyclization of methyl 2-sulfenamoylbenzoate after heating, to give 2-(2-methoxycarbonylphenylthio)-1,2-benzisothiazolin-3-ones. Several types of 2-sulfenyl-1,2-benzisothiazolin-3-ones were synthesized from the 2-sulfenamoylbenzoates.