The chemistry of 2,1-benzisothiazoles. Part VI. Quaternary salts and their decomposition by base to o-aminobenzaldehydes
Abstract
2.1-Benzisothiazoles react readily with dialkyl sulphates, alkyl bromides, and alkyl toluene-p-sulphonates at 115–120° to yield quaternary salts. Such salts are decomposed by aqueous acid or base, affording N-substituted o-aminobenzaldehydes; the parent o-aminobenzaldehyde can be obtained from the product of the reaction between 2,1-benzisothiazole and ethyl chloroformate. Bridged binuclear o-aminobenzaldehydes may also be prepared.