Jump to main content
Jump to site search

Issue 17, 1996
Previous Article Next Article

Synthesis and crystal structure of a dinuclear rhodium complex. Catalytic activity of mono- and di-nuclear rhodium phosphite complexes in hydroformylation

Abstract

A new bidentate phosphite, {bis[2-(diphenoxyphosphinoxy)-1-naphthyl]methyl}benzene L1 and a tetradentate phosphite, 1,4-bis{bis[2-(diphenoxyphosphinoxy)-1-naphthyl]methyl}benzene L2 were prepared in a facile two-step procedure involving condensation of 2-naphthol with respectively benzaldehyde or terephthaladehyde, followed by treatment with chlorodiphenoxyphosphine. The corresponding monuclear rhodium(I) complex [RhL1(acac)]1(acac = acetylacetonate) and dinuclear complexes [Rh2L2(acac)2]2 and [Rh2L2Cl2(CO)2]3 have been isolated. The fluxial behaviour of the ligand in the mono- and di-nuclear rhodium complexes in solution was studied by dynamic 1H and 31P NMR spectroscopy, showing hindered rotation in the biarylmethane units. The crystal structure of complex 2, obtained by X-ray analysis, reveals its dinuclear nature and an ‘unfolded’ geometry. Complexes 1 and 2 catalyse the hydroformylation of cyclohexene with average turnover frequencies of 428 and 344 mm–1 h–1, respectively, over 4 h. A notable increase was observed in turnover frequency during the course of reaction. High-pressure (20 bar H2–CO) IR and 1H and 31P NMR studies with complex 1 revealed a single rhodium hydride species in solution.

Back to tab navigation

Article type: Paper
DOI: 10.1039/DT9960003561
J. Chem. Soc., Dalton Trans., 1996, 3561-3569

  •   Request permissions

    Synthesis and crystal structure of a dinuclear rhodium complex. Catalytic activity of mono- and di-nuclear rhodium phosphite complexes in hydroformylation

    E. K. van den Beuken, W. G. J. de Lange, P. W. N. M. Van Leeuwen, N. Veldman, A. L. Spek and B. L. Feringa, J. Chem. Soc., Dalton Trans., 1996, 3561
    DOI: 10.1039/DT9960003561

Search articles by author

Spotlight

Advertisements