Thermoregulated phase transfer ligands and catalysis VII. Cloud point of nonionic surface-active phosphine ligands and their thermoregulated phase transfer property

A series of nonionic surface-active phosphine ligands with the general form ula, [Ro(CH2CH2O)(n)](m)PPh3-m (m=1,2), (AEOPP) has been synthesized. Cloud points of the phosphine ligands are measured and effects of changing hydro philic and lipophilic groups on the cloud point of the phosphine ligand are examined. Experiment shows that AEOPP has distinct cloud point when n is g reater than 7, R group larger than butyl and EO/Cj ratio greater than 0.5 ( where EO = n x m, Cj represents the total number of carbon atoms of both R and phenyl group). The rhodium complex of AEOPP shows thermoregulated phase transfer property in water/organic two-phase system. The complex exhibits good catalytic activity in the hydroformylation of 1-dodecene in water/orga nic two-phase medium and the conversion of the 1-dodecene and the yield of the aldehyde are 98% and 96%, respectively. (C) 1999 Elsevier Science B.V. All rights reserved.