Abstract: There is provided a process for preparing a 1,3-dialkyl-2-imidazolidinone by using an alkylene oxide as a first component, using at least one of (A) carbon dioxide and a monoalkylamine; (B) a carbon dioxide compound of the monoalkylamine; and (C) an 1,3-dialkylurea, reacting the first and second components by heating at 50° C. or higher to give 1,3-dialkyl-2-imidazolidinone, characterized in that the total molar amount of a molar feed amount of the monoalkylamine included in the component (A), a molar feed amount of the monoalkylamine part of the carbon dioxide compound of monoalkylamine, component (B), and the double of a molar feed amount of the 1,3-dialkylurea, component (C), is at least three folds of a molar feed amount of the alkylene oxide. The preparation process of this invention uses an industrially readily available alkylene oxide as a starting material and can be suitably conducted with a higher yield in an industrial scale.

Abstract: There is provided a process for preparing a 1,3-dialkyl-2-imidazolidinone by using an alkylene oxide as a first component, using at least one of (A) carbon dioxide and a monoalkylamine; (B) a carbon dioxide compound of the monoalkylamine; and (C) an 1,3-dialkylurea, reacting the first and second components by heating at 50 ° C. or higher to give 1,3-dialkyl-2-imidazolidinone, characterized in that the total molar amount of a molar feed amount of the monoalkylamine included in the component (A), a molar feed amount of the monoalkylamine part of the carbon dioxide compound of monoalkylamine, component (B), and the double of a molar feed amount of the 1,3-dialkylurea, component (C), is at least three folds of a molar feed amount of the alkylene oxide.

Abstract: This invention provides a convenient process for manufacturing 1,3-dialkyl-2-imidazolidinones in a direct one-step reaction from industrially available alkylene carbonate, N-alkylethanolamine or 1,2-diol, which can minimize forming solid materials and be readily conducted in an industrial large-scale production with a higher yield and less byproducts. The process is characterized in that alkylene carbonate, N-alkylethanolamine or 1,2-diol is reacted with monoalkylamine and carbon dioxide, alkylcarbamate alkylamine salt, and/or 1,3-dialkylurea, by heating them at 50° C. or higher in a reactor whose area in contact with at least part of the reactants and/or products is made of a metal comprising titanium or zirconium and/or an oxide thereof or inorganic glass.