SPACER-MODIFIED POLYMERIC CATALYSTS CONTAINING PHOSPHONIUM SALTS FOR REGIOSELECTIVE ADDITION-REACTION OF EPOXY COMPOUNDS WITH ACTIVE ESTERS

The catalytic activity of insoluble polymer-supported catalysts with alkylene spacer chains between polystyrene backbones and quaternary phosphonium salts (catalysts 1-19) was examined for regioselective addition of epoxy compounds (22a-c) with active esters (23a,b). The activity was strongly affected by the structure of onium salts, the degree of ring substitution (DRS), the degree of cross-linking (DC), the length of the alkylene spacer chain, and the reaction solvents. The chloride-containing catalysts exhibited higher activity than the bromide-containing catalysts. The catalysts with low DRS had a higher activity than those with high DRS. The catalysts with low DC also had a higher activity than those with high DC. The activity of the spacer-modified catalysts was higher than that of catalysts with no spacer chains. It was found that suitable combination of catalyst and solvent gave a higher activity than low molecular weight catalysts such as tetrabutylammonium bromide (20) or chloride (21). Furthermore, catalysts with suitable DRS and alkylene spacer can be reused for at least 10 runs. © 1990, American Chemical Society. All rights reserved.