Nomenclature
CAS number: 19624-22-7
Pentaboron nonahydride.
B
5H
9; mol wt 63.13.
B 85.62%, H 14.37%.
Description and references
Prepd from diborane: Stock, Mathing, Ber. 69B, 1456 (1936); Schlesinger,
Burg, J. Am. Chem. Soc. 53, 4321 (1931); 55, 4009 (1933). Molecular structure determination
by rotational spectroscopy: D. Schwoch et al., Inorg. Chem. 16, 3219 (1977).
Review of toxicity: see Decaborane(14). Review: Greenwood in Comprehensive
Inorganic Chemistry vol. 1, J. C. Bailar, Jr. et al., Eds. (Pergamon Press, Oxford, 1973) pp 792-801.
Properties
Liquid. mp -46.6°; bp 60°. d40 0.61; vp 66 mm Hg at 0°. Dec very slowly at 150°. Ignites
spontaneously in air. Hydrolyzes in water after long heating. Reacts
with ammonia to form a diammoniate.Caution
Potential symptoms of overexposure
are dizziness, headache, drowsiness and lightheadedness; incoordination,
tremor, convulsions, behavioral changes; tonic spasms of face, neck,
abdomen and limbs; irritation of eyes and skin. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH
97-140, 1997) p 242.