Silicon Tetramide, Si(NH2)4, is prepared by the general Method for preparing amides, that is, by the interaction of the acid chloride and ammonia. Thus when silicon tetrachloride and ammonia interact in benzene solution below 0° C., or when liquid ammonia and the tetrachloride are mixed together below 0° C., a white solid is formed which is a mixture of the tetramide and the necessary by-product, ammonium chloride:
SiCl4 + 8NH3 = Si(NH2)4 + NH4Cl.
From this mixture liquid ammonia dissolves ammonium chloride, leaving silicon tetramide as an unstable, amorphous white substance which above 0° C. loses ammonia, passing into the di-imide. Water decomposes the tetramide into silicic acid and ammonia. |