Nomenclature
CAS number: 7782-92-5
Sodamide.
H
2NNa; mol wt 39.01.
H 5.17%, N 35.91%, Na 58.93%.
NaNH
2.
Description and references
Prepd from sodium metal and gaseous ammonia
(or liq ammonia with ferric nitrate catalyst): Dennis, Browne, Inorg. Synth. 1, 74 (1939); Greenlee,
Henne, ibid. 2, 128
(1946); Schenk in Handbook of Preparative
Inorganic Chemistry vol. 1, G. Brauer, Ed.
(Academic Press, New York, 2nd ed., 1963) pp 465-468. Alternate method:
Bergstrom, Org. Synth. coll.
vol. III, 778 (1955).
Properties
Crystals, mp 210°. The commercial product may be a white to olive-green
solid with sea-shell fracture. Begins to volatilize at 400° and dec
into its elements between 500 and 600°. Heat of formation of solid
(18°; 1 atm): -32.26 kcal/mole. Heat of soln (21°): -31.06 kcal/mole.
Soly in liquid ammonia at 20° = about 0.1%. Reacts violently with
water forming NaOH and NH3. The reaction with alcohol
is considerably slower. Should be stored in sealed containers which
prevent all contact with air during storage: Bergstrom, Fernelius, Chem. Rev. 12, 63, 75, 78 (1933).
When exposed to the atmosphere, sodium amide rapidly absorbs H2O and CO2. When only limited absorption takes
place, as in poorly sealed containers, products are formed which render
the resulting mixture highly explosive. The formation of oxidation
products is accompanied by the development of a yellow or brownish
color. If such a change is noticed, the substance should be destroyed
at once. This is conveniently accomplished by covering with much
benzene, toluene, or kerosene and slowly adding dil ethanol with stirring.Caution
Intensely irritating to skin, eyes,
mucous membranes.Use
Dehydrating agent. In the production of indigo
and hydrazine. Intermediate in the prepn of sodium cyanide. In ammonolysis
reactions, in Claisen condensations, alkylation of nitriles and ketones,
synthesis of ethynyl compds, acetylenic carbinols. Fused NaNH
2 dissolves metallic Mg, Zn, Mo, W, quartz, glass, silicates
and other substances.