REDUCTION OF RAMETHYLHEXAHYDROIMIDAZO[2,1-D][1,2,5]DITHIAZEPINE WITH BORANE

Treatment of ramethylhexahydroimidazo[2,1-d][1,2,5]dithiazepine (3) wi th boranetetrahydrofuran complex (BH3.thf) gave rihydro(6,6,9,9-tetram ethylhexahydroimidazo[2,1-d] [1,2,5]dithiazepine-kappa N-1)boron (5) w hich was reduced to ,10,10-tetramethyl-1,2-dithia-5,8-diazacyclodecane (2) upon treatment with hydrochloric acid. Reduction of 3,3, etrameth yl-1,2-dithia-5,8-diazacyclodeca-4,8-diene (1) gave a mixture of (5) a nd -tetramethyl-1,2-dithia-5,8-diazacyclodecane-kappa N-5)boron (6) as intermediates which were converted into (a) with hydrochloric acid. T he structures of (2), (5) and (6) were determined by X-ray crystallogr aphy.