in tetrachloromethane addn. of soln. of (t-BuN)2S to soln. of (t-BuN)2(BMe)2S2 (dropwise), treatment (18 h); sepn. of solvent, distn. (vac.); elem. anal.;

in toluene addn. of boiling soln. of (t-BuN)2(BMe)2S2 to suspn. of Na (stirring), refluxing (heating, 20 h), sepn. of Na (decantation), sepn. of solvent; distn. (vac.); elem. anal.;