25966-18-1Relevant academic research and scientific papers
Rhodium(I) N-heterocyclic carbene complexes as highly selective catalysts for 1-hexene hydroformylation
Gil, Wojciech,Trzeciak, Anna M.,Ziolkowski, Jozef J.
, p. 4131 - 4138 (2008)
Rhodium(I) carbene complexes of the type [Rh(NHC)(cod)X] (where NHC = N-heterocyclic carbene obtained from dialkylimidazolium cation; cod = 1,5-cyclooctadiene; X = Cl, Br, I, SCN) with P(OPh)3 as a modifying ligand have been found to be very active catalysts for 1-hexene hydroformylation under mild conditions (80 °C, 10 atm of H2/CO, 4 h). Even at a low rhodium concentration (1-hexene]/[Rh] = 2000), aldehydes have been obtained in yields of up to 90% with a high n/iso ratio of ca. 7. During the catalytic process, rhodium(1) carbene complexes, [Rh(NHC)(P(OPh)3) 2X], reacted with H2/CO, giving a catalytically active rhodium(I) hydrido complex containing an N-heterocyclic carbene ligand. The presence of [HRh(CO)(P(OPh)3)3] and [Rh(NHC)(P(OPh) 3)(CO)X] complexes in the catalytic system has been confirmed. When P(OCH2CF3)3 was used as modifying ligand with [Rh(NHC)(cod)Br] as catalyst precursor, formation of [HRh(CO)(NHC)(P(OCH 2CF3)3)2] with a square-pyramidal structure was evidenced by 1H and 31P NMR.
Some reactions of compounds of the type [(diene)RhX]2 (diene = cycloocta-1,5-diene, bicyclo[2.2.1]hepta-2,5-diene; X = Cl, Br) with tertiary phosphines and phosphites
Haines, Linda M.
, p. 1517 - 1520 (2008/10/08)
The reactions of various monodentate ligands with the dimeric compounds [(diene)RhX]2 (diene = C8H12, X = Cl, Br; diene = C7H8, X = Cl) are described. Whereas it has been previously established that a
