Abstract: The present invention provides a process for producing an N-vinyl compound, which comprises subjecting an N-(-alkoxyalkyl) compound to gas phase intramolecular alcohol elimination to convert said compound to an N-vinyl compound directly in one step, wherein a solid oxide containing phosphorus and an alkali metal and/or an alkaline earth metal is used as a catalyst. This process need not use any solvent or any auxiliary raw material and consequently can produce an N-vinyl compound simply and safely without generating any waste material derived from the auxiliary raw material.

Abstract: A method for preparing isocyanates by the thermal decomposition of carbamates in the presence of a sintered oxide as catalyst under gaseous phase condition. The sintered oxide is composed of at least one element selected from the group consisting of boron, aluminum, silicon, tin, lead, antimony, zinc, yttrium, lanthanum, titanium, zirconium, niobium, tungsten, and iron. The sintered oxide may be composed of at least one element selected from the group consisting of phosphorus, alkali metal element, and alkaline earth metal element.