The new water-soluble amphiphilic phosphines R-(C6H4)-(OCH2CH2)nP(Ph)C H2CH2SO3-Na (R = tert-octyl, n̄ = 1.4, 5.1, 11.2; R = n-nonyl, n̄ = 1.6, 5.6, 11.4) and RP(Ph)CH2CH2SO3Na (R = n-octyl, CH3(OCH2CH2)3) have been synthesized and characterized by NMR (1H, 13C, 31P) and ES mass spectroscopy. The respective Pd(II) complexes were prepared by reaction with PdCl2(COD). Water solutions of ligands and Pd(II) complexes exhibit surfactant properties that have been studied by surface tension measurements. The critical micelle concentration (cmc) and the area occupied per molecule absorbed in the air/water interface were determined. These data show that the cmc's of ligands are significantly higher than those of their respective metal complexes. This finding can be understood by considering the metal complex as a pseudo gemini surfactant. The values of area occupied per molecule in the interface show that ligands with a middle polyether chain yielded the metal complexes with the highest metal concentration in the interface.
Valls, E., Solsona, A., Suades, J., Mathieu, R., Comelles, F., & López-Iglesias, C. (2002). Synthesis and characterization of new amphiphilic phosphines and palladium metallosurfactants. Organometallics, 21(12), 2473-2480. https://doi.org/10.1021/om020067q