| 摘要 |
<p>PURPOSE:To suppress formation of high-boiling by-products and obtain a compound useful as a raw material for polyurethanes or carbamate based agricultural chemicals in good yield at a low cost, by subjecting carbamic acid esters to thermal decomposition reaction in the presence of a catalyst of simple substance boron and/or a compound containing boron. CONSTITUTION:Carbamic acid esters are subjected to thermal decomposition reaction in the presence of a catalyst in a solvent (e.g. bromonaphthalene or n-hexadecane) inert to isocyanates at 100-350 deg.C for several min - several tens of hr to afford the aimed substance. Simple substance boron or at least one compound, selected from the following group and containing boron or both are used as the catalyst. (a) alkali metal or alkaline earth metal borates, (b) alkaline earth metal borides, (c) titanium family metal borides, (d) chromium family metal borides, (e) manganese boride, iron boride, cobalt boride and nickel boride, (f) boric acid esters and (g) boron carbide, boron silicide, boron nitride and boron oxide.</p> |
