Hydrides of Boron
Elements of group 13 do not react directly with hydrogen. Their hydrides are prepared by indirect methods.
Boron forms a large number of hydrides, called boranes, of the general formula BnHn+4 and BnHn+6. The most important of these boranes is B2H6, called diborane. It is prepared by the following methods
Mg3B2 + H3PO4 Mixture of boranes B2H6
4BCl3 + 3LiAlH4 2B2H6 + 3LiCl + 3AlCl3
2NaBH4 + I2 B2H6 + H2 + 2NaI
(in polyether solvent)