The formation of hydridorhodium(I) complexes with the amphiphilic phosphines was studied by NMR methods and IR spectroscopy. Two approaches were used: (1) the substitution reaction of triphenylphosphine in RhH(CO)(PPh 3 ) 3 by an amphiphilic phosphine and (2) a reaction between the precursor Rh(acac) (CO) 2 , syngas and the amphiphilic ligand in hydroformylation reaction conditions. Both approaches show the formation of P-coordinated hydridorhodium(I) complexes, and no relevant chelated (P, O) complexes were recognised. The biphasic rhodium-catalysed hydroformylation of 1-octene with the following water-soluble amphiphilic phosphines was studied: 4-(R)C 6 H 4 (OCH 2 CH 2 ) n P(Ph)CH 2 CH 2 SO 3 Na (R = 2,2,4,4-tetramethylbutyl, n̄ = 1.4, 5.1, 11.2, R = n-nonyl, n̄ = 1.6, 5.6, 11.4), and RP(Ph)CH 2 CH 2 SO 3 Na (R = n-octyl, CH 3 (OCH 2 CH 2 ) 2 OCH 2 CH 2 ). Ligands with a hydrophobic group and a short polyether chain led to the higher conversion. This result is ascribed to the ability of these ligands to increase the metal concentration in the organic phase. © 2003 Elsevier Science B.V. All rights reserved.
|Journal||Journal of Organometallic Chemistry|
|Publication status||Published - 3 Mar 2003|
- Amphiphilic phosphines
- Biphasic hydroformylation
- Hydridorhodium(I) complexes