63783-08-4Relevant academic research and scientific papers
Selective Formation and Characterization of a RhIII Difluorido λ4-Trifluorosulfanyl Complex
Pfister, Nils,Braun, Thomas,Wittwer, Philipp,Ahrens, Mike
, p. 1064 - 1070 (2018/09/21)
A general route to access the Vaska type fluorido complexes trans-[Rh(F)(CO)(PR3)2] [R = Et (6), Ph (7), iPr (8), Cy (9), tBu (10)] was developed by treatment of trans-[Rh(Cl)(CO)(PR3)2] (1–5) with Me4NF. The molecular structures of 8 and 9 were determined by X-ray crystallography. Treatment of the complex 6 with SF4 resulted in the selective formation of complex cis,trans-[Rh(F)2(SF3)(CO)(PEt3)2] (11), whereas the other fluoride complexes didn't react.
Migration of a hydride ligand to a difluorocarbene ligand bound to rhodium. The synthesis and crystal structure of RhCl2(CF2H)(PPh3)2
Burrell, A. K.,Clark, G. R.,Jeffrey, J. G.,Rickard, C. E. F.,Roper, W. R.
, p. 391 - 408 (2007/10/02)
Rh(CF3)(CO)(PPh3)2 has been made by treating RhH(CO)(PPh3)3 with Hg(CF3)2, and found to display reactivity consistent with a 16 e-, d8 complex, in that it undergoes addition of a number of small molecules, including O2, X2 (X = Cl, Br, I) and MeI.Treatment of Rh(CF3)(CO)(PPh3)2 with aqueous acids results in hydrolysis of the trifluoromethyl group to a carbonyl ligand.Confirmation that this reaction proceeds via a difluorocarbene intermediate came from the reaction with dry HCl, which gave RhCl2(CF2H)(CO)(PPh3)2.A study of this reaction, by multinuclear NMR spectroscopy and 2H-labelling experiments led to the proposal of a mechanism for the formation of RhCl2(CF2H)(CO)(PPh3)2 that involves hydride migration to a cationic difluorocarbene ligand bound to rhodium.Another difluoromethyl complex RhCl2(CF2H)(PPh3)2 is formed when RhHCl2(PPh3)3 is treated with Hg(CF3)2.The crystal structure of this complex has been determined, and displays square pyramidal geometry with the CF2H ligand occupying the apical position.
Relative affinities of carbonylbis(triphenylphosphine)rhodium(I) and related cations for anionic ligands in CH2Cl2
Araghizadeh, Farshid,Branan, Daniel M.,Hoffman, Norris W.,Jones, John H.,McElroy, E. Andrew,Miller, Nathan C.,Ramage, David L.,Salazar, Anna Battaglia,Young, Sidney H.
, p. 3752 - 3755 (2008/10/08)
Infrared spectroscopy has been used to determine the relative anion affinities in CH2Cl2 of Rh(PPh3)2(CO)+ and Rh(AsPh3)2(CO)+ via measurement of equilibrium constants for the metatheses RhL2(CO)Y + PPN+Z- = RhL2(CO)Z + PPN+Y-. Observed for L = PPh3 was the anion affinity trend NCO- ? O2CMe- ～ O2CPh- ? F- ～ NCS- > Cl- > Br- > I- ? ONO2- ～ O2CCF3- ? OTf- ～ OClO3-. A smaller series for L = AsPh3 displayed a similar trend, but with positions of NCS- and Cl- reversed. For most anion pairs studied, the equilibrium lies so far to the left or right that only limits could be calculated, given the inherent experimental limitations. For L = PPh3, the equilibrium constant for replacement of the least preferred anion by the most can be inferred as >1019. Rh(PCy3)2(CO)Cl and Rh(PCy3)2(CO)Z (Z = NCS, NCSe, O2CMe; but not F, O2CPh, and NCO) interact strongly in solution and thus limit study of that series.
