An efficient construction of 2-thioxo-1,3-benzothiazin-4-ones has been developed via a PPh3-promoted desulfurative 4 + 2 annulation between benzoc1,2dithiol-3-ones and isothiocyanates. This strategy is characterized by its mild reaction conditions, operational simplicity, excellent yields, wide functional group tolerance, accessible scalability, and practical transformations.
Wang et al. (Wed,) studied this question.