Various types of electrophilicsubstitution of monohomoperylene (1) and its 11,11-difluoro derivative (2) have been studied, viz. Bromination, nitration, acylation, formylation and sulfonation. Bromination with N-bromosuccinimide (NBS) of 1 in dichloromethane leads to initial substitution mainly at the α positions 2 and 10, i.e., of the annuleno moiety, followed by further substitution of the β positions
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.