The sodium hydride product is a 60±3% microcrystalline dispersion of sodium hydride in mineral oil. Typical particle size ranges from 5 to 50 microns. Sodium hydride can be used in condensation and alkylation reactions. And can be used as polymerization catalyst.
Molecular formula NaH
Molecular weight 24.00
Form the microcrystalline dispersion of gray powder in mineral oil
Specification 60%NaH3%
Solubility insoluble in all organic solvents as well as liquid ammonia and amines
Thinner mineral oil, 403%
Flash point 340F
Specific gravity 0.84-0.86
Mineral oil can be freely miscible with a wide range of hydrocarbons without affecting the activity of sodium hydride. Examples are hexane heptane, diethyl ether, diethyl ether, and toluene.
Thermal stability
Sodium hydride is heated and begins to dissociate at 255. The relationship between the equilibrium pressure and temperature can be expressed by the following equation: Log10Pmm=-6100/TK+11.66(1) 300 or more, the oil will be attacked by sodium hydride.
Water reactivity
Attention! Formation of sodium hydride dispersion with water The reaction of hydrogen gas with sodium hydroxide is violent and exothermic. The combustion of hydrogen will occur.
[Application]
Condensation - Sodium hydride in oil has the same capacity to act as a shrinking agent in acetoacetate, Claisen, Stobbe, Dieckmann and related condensations as sodium metallics and sodium alcohols. Compared with other condensing agents, it has the following advantages:
(1) It is more powerful and reacts much faster;
(2) Large excess is not necessary;
(3) there is no need to distill the alcohol to promote condensation, and no additional alcohol is formed;
(4) Avoid side reactions such as reduction;
(5) The degree of reaction can be measured from the hydrogen that occurs.
Alkylation - The alkylation of aromatic and heterocyclic amines such as 2-aminopyridine and phenothiazine is easily accomplished at high yields using toluene-dimethylformamide.