Nomenclature
CAS number: 75-12-7
Methanamide; carbamaldehyde; formimidic acid.
CH
3NO; mol wt 45.04.
C 26.67%, H 6.71%, N 31.10%, O 35.52%.
HCONH
2.
Description and references
Prepd on a large scale from carbon monoxide
and ammonia at high press. and temp: Meyer, Orthner, Ber. 54, 1705 (1921); 55, 857 (1922); Meyer, DE 390798 (1924); DE 392409 (1924); DE 414257 (1925 to BASF); Wietzel,
Herbst, US 1843434 (1932 to I. G. Farben). Toxicity study: Pham-Huu-Chank et al., Toxicol. Appl. Pharmacol. 26, 596 (1973). Review: C. L. Eberling in Kirk-Othmer Encyclopedia of Chemical Technology vol. 11 (Wiley-Interscience, New York, 3rd ed., 1980)
pp 258-263.
Properties
Slightly viscous, odorless, colorless liq. Industrial
grades may have faint odor of ammonia. mp 2.55°. bp760 210.5° (partial decomp into CO and NH3 at atm pressure beginning at 180°); bp400 193.5°; bp200 175.5°; bp60 147.0°; bp20 122.5°; bp10 109.5°; bp1.0 70.5°. d415 1.13756; d420 1.13340; d430 1.12483. Dielectric constant ε
= 84. Viscosity η × 105 at 15° = 4320, at 30° = 2926.
Surface tension γ at 20° = 58.35. nD15 1.44911; nD20 1.44754; nD110 1.4170; nD130 1.4095. Flash pt, open cup: 310°F (154°C). pH of 0.5
molar aq soln 7.1. Misc with water, methanol, ethanol, acetone, acetic
acid, dioxane, ethylene glycol, U.S.P. glycerol, phenol. Very slightly
sol in ether, benzene. Dissolves casein, glucose, zein, tannins,
starch, lignin, polyvinyl alcohol, cellulose acetate, nylon, the chlorides
of copper, lead, zinc, tin, cobalt, iron, aluminum, nickel, the acetates
of the alkali metals, some inorganic sulfates and nitrates. LD50 in mice, rats (g/kg): 4.6, 5.7 i.p. (Pham-Huu-Chanh).Caution
Potential symptoms of overexposure
are irritation of eyes, skin, mucous membranes; drowsiness, fatigue;
nausea, acidosis; skin eruptions. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140,
1997) p 148.Use
As ionizing solvent, manuf formic esters, hydrocyanic
acid by catalytic dehydration, as softener for paper, animal glues,
water-sol gums.