2X+B2H6⟶[BH2(X)2]+[BH4]− the amine(s) X is/are:
NH3
CH3NH2
(CH3)2NH
The reaction:
2X+B2H6⟶[BH2(X)2]+[BH4]−
Is consistent with X being a non-tertiary amine. As in, ammonia, methylamine and dimethylamine all would definitely give this reaction. However, with a tertiary amine, an adduct is formed:
2R3N+B2H6⟶2H3B(NR3)