Hydroformylation of 1,5-Hexadiene Catalyzed by Rhodium Complexes in Supercritical Carbon Dioxide and in Toluene: Effects of Fluorinated Phosphane Ligands and Reaction Conditions

✍ Scribed by Shin-ichiro Fujita; Shinya Fujisawa; Bhalchandra M. Bhanage; Yutaka Ikushima; Masahiko Arai

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 174 KB
• Volume: 2004
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.200300746

✦ Synopsis

Abstract

Rhodium‐catalyzed hydroformylation of 1,5‐hexadiene to dialdehydes was investigated in compressed CO~2~ and in toluene using different fluorinated phosphane compounds as ligands at a temperature of 60 °C. Product yields depend greatly on the ligand used and, of the ligands examined, tris[3,5‐bis(trifluoromethyl)phenyl]phosphane is the most effective for the production of dialdehydes both in supercritical CO~2~ (scCO~2~) and in toluene. The total yield of the dialdehydes passes through a minimum at about 9 MPa as the CO~2~ pressure is increased and increases appreciably as the H~2~ pressure in scCO~2~ increases. The effect of the syngas (H~2~/CO) and H~2~ pressures on the reaction in scCO~2~ is different from that in toluene. It has been suggested that scCO~2~ promotes the hydroformylation reaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)