THERMOREGULATED PHASE-TRANSFER LIGANDS AN D CATALYSIS - (V) - SYNTHESIS AND CATALYTIC PROPERTIES OF MONO-P-POLYOXYETHYLENE AND DI-P-POLYOXYETHYLENE SUBSTITUTED TRIPHENYLPHOSPHINES

Mono-and di-p-polyoxyethylene substituted triphenylphosphines (1) were prepared by the ethoxylation of diphenyl (4-hydroxyphenyl)phosphine a nd phenyldi(4-hydroxyphenyl)phosphine. RhCl3/1 complexes have desirabl e catalytic properties in aqueous/organic biphasic hydroformylation of 1-hexene, with a conversion up to 95%, and can be reused for 5 times without loss in activity, Since ligands 1 possess inverse temperature- dependent solubility in water, the hydroformylation has undergone an i nteresting process of thermoregulated phase-transfer catalysis, in whi ch the catalyst transfers into the organic phase to catalyze the react ion at a higher temperature, and returns to the aqueous phase to be se parated from the product at a lower temperature after the reaction is completed.