3247. 1,1-Dimethylhydrazine

Nomenclature

CAS number: 57-14-7
unsym-Dimethylhydrazine; asym-dimethylhydrazine; N,N-dimethylhydrazine; UDMH; Dimazine.
C2H8N2; mol wt 60.10.
C 39.97%, H 13.42%, N 46.61%.
(CH3)2NNH2.

Description and references

Prepd industrially by the reaction of dimethylamine and chloramine; by reduction of nitrosodimethylamine (obtained by treating a dimethylamine salt with sodium nitrite): Hatt, Org. Synth. coll. vol. II, 211 (1943). Toxicity studies: Witkin, Arch. Ind. Health 13, 34 (1956); Cornish, Hartung, Toxicol. Appl. Pharmacol. 15, 62 (1969). Review of carcinogenic risk: IARC Monographs 4, 137-143 (1974); of toxicology and human exposure: Toxicological Profile for Hydrazines (PB98-101025, 1997) 224 pp.

Properties

Flammable. Hygroscopic, mobile liquid. Fumes in air and gradually turns yellow. Characteristic ammonia-like fishy odor of aliphatic hydrazines. d422 0.791; d2525 0.782. mp -58°. bp760 63.9°. nD22.3 1.40753. Miscible with water with evolution of heat. Also miscible with alcohol, ether, dimethylformamide, hydrocarbons. LD50 in mice, rats (mg/kg): 265, 122 orally; 250, 119 i.v. (Witkin).

Derivative

Hydrochloride.
C2H8N2.HCl; mol wt 96.56.
C 24.88%, H 9.39%, N 29.01%, Cl 36.72%.

Properties

Hygroscopic crystals from abs ethanol, mp 83°. Sol in water, ethanol. Practically insol in ether.

Caution

Potential symptoms of overexposure are irritation of eyes and skin; choking, chest pain and dyspnea; lethargy; nausea; anoxia; convulsions; liver injury. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 114. See also Patty's Industrial Hygiene and Toxicology vol. 2A, G. D. Clayton, F. E. Clayton, Eds. (Wiley-Interscience, New York, 3rd ed., 1981) pp 2801-2803. 1,1-Dimethylhydrazine is reasonably anticipated to be a human carcinogen: Report on Carcinogens, Eleventh Edition (PB2005-104914, 2004) p III-107.

Use

Base in rocket fuel formulations.