The microwave-assisted Dötz benzannulation process
作者:Edward J. Hutchinson、William J. Kerr、Euan J. Magennis
DOI:10.1039/b206981b
日期:——
Chromium carbene-mediated Dötz benzannulation has been shown to proceed remarkably rapidly and with enhanced efficiency under developed microwave-assisted conditions.
This process is a process for production of a vinyl chloride polymer by suspension polymerization or emulsion polymerization of vinyl chloride monomer or a mixture of vinyl chloride monomer with a vinyl monomer copolymerizable with said vinyl chloride monomer in an aqueous medium, characterized in that the polymerization is carried out in a polymerizer, the inner wall surface and portions of the auxiliary equipment thereof which may come into contact with the monomer during polymerization being previously coated with a scaling preventive comprising at least one selected from dyes, pigments and aromatic or heterocyclic compounds having at least 5 conjugated π bonds, while controlling the chloride ion concentration in the reaction mixture to not higher than 100 ppm. According to said process, scaling onto the inner wall surface of a polymerizer, etc. during polymerization can be prevented effectively and surely.