METHOD FOR PRODUCING META-XYLYLENEDIISOCYANATES

摘要

A method for producing meta-xylylenediisocyanates includes a reaction step in which monohalogenated benzenes, formaldehydes, and an amide compound represented by general formula (1) below are allowed to react in the presence of an acidic liquid to produce a bisamide compound; a dehalogenation step in which in the bisamide compound, the halogen atom derived from the monohalogenated benzenes is replaced with a hydrogen atom; and a thermal decomposition step in which the bisamide compound from which the halogen atom is eliminated is subjected to thermal decomposition. In the reaction step, the acidic liquid contains inorganic acid, the equivalent ratio of the hydrogen atom of the inorganic acid relative to the monohalogenated benzenes is more than 14, the acidic liquid has an inorganic acid concentration of more than 90 mass %, and the reaction temperature is more than 10° C.;General formula (1):;;wherein R1 represents an alkoxy group or an amino group.

主权项

1. A method for producing meta-xylylenediisocyanate, comprising:
a reaction step in which monohalogenated benzene, formaldehydes, and an amide compound represented by general formula (1) below are allowed to react in the presence of an acidic liquid to produce a bisamide compound, a dehalogenation step in which in the bisamide compound, the halogen atom derived from the monohalogenated benzene is replaced with a hydrogen atom, and a thermal decomposition step in which the bisamide compound from which the halogen atom is eliminated is subjected to thermal decomposition,wherein in the reaction step,
the acidic liquid contains inorganic acid, the equivalent ratio of the hydrogen atom of the inorganic acid relative to the monohalogenated benzene is more than 14, the acidic liquid has an inorganic acid concentration of more than 90 mass %, and the reaction temperature is more than 10° C.:
General formula (1):(in general formula (1), R1 represents an alkoxy group or an amino group).