331. Aluminum Borohydride

Nomenclature

CAS number: 16962-07-5
Tetrahydroborate(1) aluminum (3:1); aluminum tetrahydroborate.
AlB3H12; mol wt 71.51.
Al 37.73%, B 45.35%, H 16.91%.
Al(BH4)3.

Description and references

Prepn from alkali metal hydride and aluminum halide: Schlesinger et al., J. Am. Chem. Soc. 75, 209 (1953); Hinkamp, Hnizda, Ind. Eng. Chem. 47, 1560 (1955); Kollonitsch, Fuchs, Nature 176, 1081 (1955); Hinkamp, US 2854312 (1958 to Ethyl Corp.); Schechter, US 2913306 (1959 to Callery Chem.); from trimethylaluminum and diborane: Schlesinger et al., J. Am. Chem. Soc. 61, 536 (1939).

Properties

Liquid. Spontaneously combustible, dangerous when wet. mp 64.5°; bp 44.5°; bp119 0°. Reacts vigorously with water and hydrogen chloride to liberate hydrogen; ignites in air; decomposes slowly even at room temp evolving hydrogen. Forms addn products with dimethyl ether, trimethylamine and ammonia.

Use

Reducing agent; prepn of borohydrides of heavy metals; fuel for jet engines and rockets.