in toluene all manipulations under N2, Ar or high vac.; dropwise addn. of BBr3 to a soln. of tris(1,3,2-dithiaborolan-2-yl)amine in toluene at -40°C; thawing to room temp.; stirring for 12 h;; removal of the volatiles under reduced pressure; fractional distn. (40°C, 1 Torr); not isolated, detd. by (11)B NMR spectroscopy;;