Beryllium hydride, BeH

Beryllium hydride (BeH ) liberates hydrogen gas when mixed with water. It is used as a source of hydrogen in experimental rockets and fuel cells. 

Barrier values of internal rotation, 381 Benzene photochemical studies, 200 Beryllium, hydride ion (BeH+) electron correlation, 324 ion (Be2f), 299... 

The beryllium hydride derivative [TpBut]BeH is obtained by metathesis of either [TpBut]BeCl or [TpBut]BeBr with LiAlH4 in Et20 at room temperature [Eq. (27)] (56). 

Diethylberyllium forms an anionic complex, NaOEtJEt BeH], when stirred with sodium hydride in ether and part of its crystal structure is shown in Fig. 3.13. The presence of the Et Be H unit should be noted, the [Et Be H ] " anion being isoelectronic with Et B H. It is likely that the bridging hydrogen atoms (located in the structure analysis) are electronically more closely associated with beryllium than with sodium. The four rather than two thin lines from oxygen indicate that the ethyl groups of the coordinated ether molecules can occupy two alternative positions. 

Cautious pyrolysis of di-isobutylberyllium gives the oligomeric (in benzene) Bu BeH which adds to olefins very much faster than do the alkylberyllium hydride ether complexes. Alkylberyllium hydrides, even as ether complexes, react very rapidly with azomethine and carbonyl bonds, giving amino- and alkoxy-beryllium alkyls (discussed below pp 113-117), e.g. 

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