Transition-metal-free skeletal editing of benzoisothiazol-3-ones to 2,3-dihydrobenzothiazin-4-ones via a single-carbon insertion

Transition-metal-free ring-expansion of benzoisothiazol-3-ones has been established to synthesize 2,3-dihydrobenzothiazin-4-ones via a single-carbon insertion. A variety of 2,3-dihydrobenzothiazin-4-ones have been prepared with good yields. The use of aldehydes and ketones...