Boron hydrido complex

In its complexes, except for those of molecular hydrogen, hydrogen is always treated as anionic. Hydrido is used for hydrogen coordinating to all elements including boron.3... 

In covalent hydrides, hydrogen and the metal are linked by a covalent bond. Aluminum, silicon, germaninm, arsenic, and tin are some of the metals whose covalent hydride structures have been stndied extensively. Some ionic hydrides, snch as LiH or MgH2, exhibit partial covalent character. The complex hydrides, such as lithium aluminum hydride and sodium borohydride, contain two different metal atoms, usually an alkali metal cation bound to a complex hydrido anion. The general formula for these compounds is M(M H4) , where the tetrahedral M H4 contains a group IIIA metal such as boron. 

Similar dehydrogenation processes can be effected for aminoborane complexes (Scheme 12), although, in both cases, the use of the dihydrogen acceptor ferfbutyl ethene (the) is required to drive the formation of the unsaturated boron-containing l%and, and the process is therefore invariably irreversible. In the case of [(p-cym)Ru(PCy3)(H)(=BN Pr2)] (55, as the [BAr4] salt)—formulated as a (hydrido)ruthenium -aminoborane... 

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