Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.623751
Title: Mechanism of hydroformylation of alkenes by Rhodium catalysts
Author: Brown, Charles Kennington
Awarding Body: University of London
Current Institution: Imperial College London
Date of Award: 1971
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Abstract:
The nydroformylation of alkenes using hydridocarbonyltris(tri-phenylphosphine)rhodium(I), RhH(C0)(PPh3)3, under mild conditions (ca 25° and 1 atm.) is described. The dependence of rate, substrate specificity and product distribution on catalyst concentration, partial pressures of carbon monoxide and hydrogen and temperature is discussed in terms of possible mechanisms. The presence of excess triphenylphosphine is important in achieving nigh yields of straight-chain aldehydes from alk-l-enes and the use of molten PPh3 as solvent allows high product specificity to be maintained at higher temperature and pressure (ca 100° and 300-700 lb.in.-2). Reactions of RhH(CO) (PPn3)3, IrH(C0)(PPh3)3 and IrR(CO)2(PPh3)2 with alkenes and CO, H2 or HC1 to give alkyl and acyl species analogous to proposed intermediates in hydroformylation are described. The reactions of these species are shown to be consistent with the proposed hydroformylation mechanism. In particular the reversible carbonylation and CO-insertion reactions of the rhodium(I) and iridium(I) species and the inhibition of reactions of H2 and HC1 with M(COR)(C0)2(PPh3)2, M = Rh, Ir, by CO are noted.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.623751  DOI: Not available
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