35679-01-7Relevant academic research and scientific papers
Formation of anionic carbonylrhodium complexes from Wilkinson's complexes under conditions of hydroformylation of formaldehyde
Ezhova, N. N.,Korneeva, G. A.,Kurkin, V. I.,Filatova, M. P.,Slivinsky, E. V.
, p. 836 - 839 (2007/10/02)
The compositions and the dynamics of transformations of carbonylrhodium complexes formed from Wilkinson's complexes, RhCl(PPh3)3, dissolved in mesitylene-N,N-dimethylacetamide (DMAA) mixtures in which the DMAA concentration varied from 0 to 100 percent, in an atmosphere of synthesis gas (pCO+H2 = 6 MPa, T = 373 K) were investigated in situ by IR spectroscopy.The anion complexes, - (x = 1, 2; y = 1, 0) and -, which are the centers of formaldehyde hydrofomylation, are produced in noticeable quantities when 100 percent DMAA is used as a solvent.Separate steps of the formation of anionic complexes from RhCl(PPh3)3 have been identified.Under the conditions of hydroformylation of formaldehyde, CH2O participates in the formation of the anionic complexes along with DMAA.
Aryldiazenide complexes. Synthesis and X-ray structure of trans-chlorobis(triphenylphosphine)((p -methoxyphenyl)diazenido) rhodium tetrafluoroborate-bis(dichloromethane), [RhCl(PPh3)2(p-N2C6H 4OMe)][BF4]·2CH2Cl2
Einstein, Frederick W. B.,Jones, Richard H.,Zhang, Ya-Mei,Sutton, Derek
, p. 1004 - 1010 (2008/10/08)
The complex [RhCl(PPh3)2(p-N2C6H 4OMe)][BF4] (1) and its bis(acetone) and bis(dichloromethane) solvates (1·2Me2CO and 1·CH2Cl2) have been synthesized from the reaction of [RhCl(PPh3)2]2 with [p-N2C6H4OMe] [BF4] in acetone. The X-ray crystal structure of 1·2CH2Cl2 has been determined. 1·2CH2Cl2 crystallizes in the orthorhombic space group Pnma with a = 22.573 (3) A?, b = 21.961 (3) A?, c = 9.522 (2) A?, V = 4720 A?3, Z = 4, and Dcalcd = 1.16 g cm-3. The structure was solved by using 2181 observed reflections in the range 4° F = 0.044 (RwF = 0.052). The cation [RhCl(PPh3)2(p-N2C6H 4OMe)]+ is square-planar with a singly bent Rh-N2Ar moiety (Ar = p-C6H4OMe), consistent with the formal view that it is a complex of Rh(I) and N2Ar+. Important dimensions are Rh-N(1) = 1.793 (8) A?, N(1)-N(2) = 1.157 (11) A?, Rh-N(1)-N(2) = 179.4 (7)°, and N(1)-N(2)-C(aryl) = 141.3 (9)°. Complex 1 reacts with hydrogen chloride to form first the new cationic aryldiazene complex (4) with δ(NH) at 10.64, formulated as [RhCl2(PPh3)2(p-NHNC6H 4OMe)][BF4], and subsequently the known neutral aryldiazene complex RhCl3(PPh3)2(p-NHNC6H 4OMe) (3) with δ(NH) at 11.54. Complex 1 is transformed into the known neutral aryldiazenide complex RhCl2(PPh3)2(p-N2C6H 4OMe) (2) by LiCl, and the reaction is reversed with AgBF4. Reaction of 1 with PPh3 at low temperature forms an unstable green complex having v(NN) at 1659 cm-1 that is also formed in the reaction of RhCl(PPh3)3 with [p-N2C6H4OMe][BF4] and is tentatively identified as [RhCl(PPh3)3(p-N2C6H 4OMe)][BF4] as originally suggested by Baird and Wilkinson.
