NUCLEOPHILIC-SUBSTITUTION REACTIONS OF 1,4-DICHLOROBENZENE CHROMIUM TRICARBONYL WITH MONOPHENOXIDES AND DIPHENOXIDES

The nucleophilic substitution reactions of 1,4-dichlorobenzene chromium tricarbonyl (1) with the phenoxide anion were investigated. The substitution of the first chlorine was very fast and gave the mono-substituted product in high yield. The substitution of the second chlorine group was significantly retarded by the presence of the phenoxy group incorporated during the first reaction and also due to the competing decomplexation reaction. The application of 1,4-dichlorobenzene chromium tricarbonyl (1) to the synthesis of new monomers was demonstrated by the preparation of 2,2'-bis [4-(4-chlorophenoxy)phenyl] propane (9). 2,2'-Bis[4-(4-chlorophenoxyl)phenyl] propane (9) was synthesized by a nucleophilic substitution reaction of 4,4'-isopropylidenediphenolate with 1,4-dichlorobenzene chromium tricarbonyl (1) followed by decomplexation with I2. 2,2'-Bis[4-(4-chlorophenoxy)-phenyl] propane (9) was also synthesized via a three-step reaction starting from the nucleophilic substitution reaction of 4,4'-isopropylidenediphenol (7a) with 1-chloro-4-nitro-benzene (10). 2,2'-Bis[4-(4-chlorophenoxy)phenyl]propane (9) was polymerized by a Ni(0)-catalyzed reaction to yield amorphous aromatic polyethers with number-average molecular weights of up to 11,200 g/mol.