Pentaborane(9) as a Source for Higher Boron Hydride Systems. A New Synthesis of nido -5,6-(Ch3)2-5,6-C2B8H10

Abstract

Pentaborane(9), B5H9, is shown to be a useful source for the production of higher boron hydride systems. Investigation of the reaction of B5H9 with sodium hydride or potassium hydride in THF or glyme to produce the tetradecahydrononaborate(l-) anion, [B9H14]-, is reported in detail, and evidence is given for reaction pathways. This anion is also obtained from the reaction of Nal with B5H9. When generated in situ from B5H9, [B9HI4]_is an intermediate in the syntheses of a number of other higher boron hydride systems: B9H13-L ligand adducts, n-B18H22, B10H14, nido-5,6-C2B8H12, and nido-5,6-(CH3)2-5,6-C2B8H10. The synthesis of B10H14reported here is an improved procedure over the earlier reported preparation from B5H9, and the preparations of nido-5,6-(CH3)2-5,6-C2B8H10and nido-5, 6-C2B8H12are new syntheses. © 1986, American Chemical Society. All rights reserved.