Metal Boron Hydrides

Stock described reactions of alkali metals with boron hydrides and the formation of such materials as M2B2H6, M2B4H10, and M2B5H9. More recent investigations, particularly of the reactions of sodium amalgam and sodium hydride with boron hydrides, suggest that Stock's materials may be intermediates and that further reactions occur. The results of Stock and those of more recent investigators can be correlated by considering the possible reaction mechanisms. The reactions of sodium hydride with the boron hydrides are less complex than the reactions with sodium amalgam. However, analogies may be drawn between the sodium amalgam and sodium hydride reactions that show similarities in mechanism. Consideration of the formation and properties of NaB3H8, Na2B10H14, and NaB10H13 and the relationships of these compounds to the parent boron hydrides leads to speculation for future metal boron hydride studies.