Hydroformylation of alkenes catalyzed by new dinuclear aryloxide- and carboxylate-bridged rhodium complexes

The new dinuclear aryloxide- and carboxylate-bridged rhodium complexes bis[μ-(2-methylphenolato)]bis[(η2:η2-cycloocta-1,5-diene)rhodium], di(μ-docosanoato)bis[(η2:η2-norborna-2,5-diene)rhodium] and bis[(μ-(adamant-1-yl)carboxylato]bis[(η2:η2-norborna-2,5-diene)rhodium] have been prepared. The complexes were tested as catalysts in the hydroformylation of styrene with a total pressure of CO/H2 (1:1) of 1000 psi, at 25 and 60 °C, and displayed a regioselectivity towards the branched aldehyde of up to 97%. The same complexes as catalysts in the hydroformylation of 1-octene displayed a regioselectivity for the linear aldehyde of up to 55%.