8592. Sodium Borohydride

Nomenclature

CAS number: 16940-66-2
Tetrahydroborate (1-) sodium (1:1).
BH4Na; mol wt 37.83.
B 28.58%, H 10.66%, Na 60.77%.
NaBH4.

Description and references

Prepn: H. I. Schlesinger et al., J. Am. Chem. Soc. 75, 205 (1953); H. C. Brown et al., J. Am. Chem. Soc. 79, 5400 (1957). Reviews: R. M. Adams, A. R. Siedle, in Boron, Metallo-boron Compounds, and Boranes (Interscience, New York, 1964) 765 pp; B. D. James, M. G. H. Walbridge, Prog. Inorg. Chem. 11, 99-231 (1970).

Properties

Hygroscopic, cubic crystals forming a dihydrate, mp 36-37°. Dangerous when wet. The anhydr material (d 1.074) is stable in dry air to 300°; dec slowly at 400° and rapidly at 500°. Supports combustion. Soly (g/100 g) in water at 25°: 55; at 60°: 88.5; liquid ammonia at 25°: 104; ethylenediamine at 75°: 22; morpholine at 25°: 1.4; pyridine at 25°: 3.1; methanol at 20°: 16.4 (reacts); ethanol at 20°: 4.0 (reacts slowly); tetrahydrofurfuryl alcohol at 20°: 14.0 (reacts slowly); tetrahydrofuran at 20°: 0.1; diglyme at 25°: 5.5; dimethylformamide at 20°: 18.0.

Use

Reducing agent for aldehydes, ketones and Schiff bases in nonaqueous solvents. Also reduces acids, esters, acid chlorides, disulfides, nitriles, inorganic anions. Further used to generate diborane, as foaming agent, as scavenger for traces of aldehyde, ketones and peroxides in organic chemicals.