反应详情

A solution of 2,2-dioxo-6-(1,1-dimethylethyl)-8-chloro-1,2,3-benzoxathiazine (2.5 g., 9.2 millimole) in acetic acid (200 ml.) contained in a Parr apparatus is hydrogenated in the presence of platinum (IV) oxide at 20° C. and a pressure (initial) of 50 p.s.i. for five minutes. The catalyst is removed by filtration and the filtrate is evaporated in vocuo to provide the title compound as a residual solid (2.35 g., 93%), m.p. 158°-160° C. Crystallization from 50% ethanol gives analytically pure 2,2-dioxo-3,4-dihydro-6-(1,1-dimethylethyl)-8-chloro-1,2,3-benzoxathiazine as colorless crystals, m.p. 162°-163° C.

1. customThe catalyst is removed by filtration
2. customthe filtrate is evaporated in vocuo