The recent discovery of tris-methanethio-borine,(CH3S) 3B, 2* 3 and methanethiodimethylborine, CH3-SB (CH3) 2, suggested that the series intermediate bis- methanethio-methylborine,(CH2S) 2BCHa, also should be found. Furthermore, since compounds of the type BXY2 often are capable of reversible disproportionation to form BX3, BY3 and BX2Y, there was some interest in the rate and extent of such reactions of CH3SB ...