Synthesis of alpha-cyanoacrylate

PURPOSE: In the presence of an interphase-transferable catalyst, the polycondensation reaction of a cyanoacetic ester and formaldehyde is effected, then, the product is subjected to depolymerization to give title compound useful as instant adhesive with industrial advantage because the dehydration treatment can rapidly be done. CONSTITUTION: The polycondensation reaction of (A) a cyanoacetic ester as ethyl cyanoacetate and (B) formaldehyde is conducted in the presence of (C) an interphase-transferable catalyst to form a polymer. After the catalyst is neutralized with sulfuric acid or so, the aqueous layer is separated, further the remaining water is separated by azeotropic distillation. Subsequently, phosphorus pentoxide is added to the product and they are heated at about 200°C to effect the depolymerization, thus giving the objective compound. The component (C) is preferably a combination of at least one of onium compounds, macrocyclic polyethers, and nonionic surfactants, with an inorganic base or their reaction product. COPYRIGHT: (C)1980,JPO&Japio