84623-58-5Relevant academic research and scientific papers
A study of syn-anti isomerism of six-coordinate ruthenium(II) complexes containing PhP(CH2CH2CH2PCy2) 2 (Cyttp) ligand
Blosser, Patrick W.,Gallucci, Judith C.,Wojcicki, Andrew
, p. 133 - 144 (2008/10/09)
A study is reported on synthesis and ligand substitution/modification reactions of the syn and anti geometric isomers of the six-coordinate ruthenium(II) complexes [mer-Ru(κ2-O2CX)(CO)(Cyttp)] n (n = 0, X = O (2); n = +1, X = Me (3), Ph (4), OMe (5), OEt (6); Cyttp = PhP(CH2CH2CH2PCy2) 2) and cis-mer-RuX2(CO)(Cyttp) (X = I (7), Cl (8)) (syn (s) and anti (a) refer to the orientation of the Ph group on the central P atom of Cyttp). Reaction of cis-mer-Ru(BF4)2(CO)(Cyttp) (1) in freshly prepared aqueous acetone solution with each of sodium carbonate, sodium acetate, and sodium benzoate affords 2a, 3a(BF4), and 4a(BF 4), respectively. The syn isomer of 2a, 2s, was synthesized by prolonged treatment of solid mer-Ru(CO)2(Cyttp) with gaseous O 2. Complexes 2a and 2s do not interconvert even on heating in toluene or methanol at reflux temperature for 24 h. Alkylation of 2a and 2s with 1 equiv. of [Me3O]BF4 or [Et3O]PF6 affords the methylcarbonato (5a(BF4) and 5s(BF4), respectively) and ethylcarbonato (6a(PF6) and 6s(PF6), respectively) complexes. Use of >2 equiv. of [Me3O]BF4 still furnishes 5s(BF4) from 2s, but yields 1 instead of 5a(BF 4) from 2a. The foregoing reactions represent, to our knowledge, the first example of different reactivity of syn and anti isomers of metal Cyttp complexes. Prolonged treatment of 2a with an excess of MeI at room temperature results in the formation of 7a. A parallel reaction of 2s with MeI to yield 7s requires heating; at ambient temperature, 5s(I) is obtained instead. Each of the complexes 2, 3(BF4)-5(BF4), and 6(PF6) is converted to 8 with retention of the syn or anti configuration by the action of hydrochloric acid. It is concluded from this and previous studies that complexes stable to ligand dissociation do not undergo syn-anti isomerization, in contrast to those that contain weakly coordinated ligands. 13C{ 1H} and 31P{1H} NMR spectroscopic generalizations were developed that enable syn-anti assignment to be made for this class of complexes. The structures of 2a (as 2a·CH 2Cl2·2H2O), 2s (as 2s·(3/4)MeC(O) Me·2H2O), and 5s (as 5s(BF4)·C 6H6) were determined by single crystal X-ray diffraction analysis. The syn and anti isomers of [mer-Ru(κ2-O 2CX)(CO)(Cyttp)]n (n = 0, X = O; n = +1, X = Me, Ph, OMe, OEt) and cis-mer-RuX2(CO)(Cyttp) (X = I or Cl) were synthesized and found to be configurationally stable with respect to isomerization and upon ligand substitution. This stability contrasts with that of previously studied related ruthenium(II) Cyttp complexes containing weakly coordinating ligands.
Syntheses and characterization of ruthenium(0) and ruthenium(II) complexes of two flexible chelating triphosphine ligands
Letts, John B.,Mazanec, Terry J.,Meek, Devon W.
, p. 695 - 704 (2008/10/08)
Treatment of RuCl3·3H2O with the triphosphine ligands PhP(CH2CH2CH2PR2)2 (ttp, R = Ph; Cyttp, R = c-C6H11) produces the complexes [RuCl2(ttp)]x, 1, and RuCl2(Cyttp), 2, respectively. The ttp complex is polymeric whereas the Cyttp product is monomeric, presumably due to steric effects of the larger cyclohexyl (Cy) group. Treatment of 1 with carbon monoxide gives cis and trans carbonyl complexes, depending on the method of preparation; only a trans-dichloro carbonyl complex was obtained in the case of Cyttp. On the basis of infrared data (v(S-O) 1280, 1112 cm-1), the SO2 adduct of 2 has a planar geometry around the sulfur atom. Both chloride ligands of 1 can readily be substituted with CH3CN or CO by using Tl+ as a halogen scavenger; the acetate ion replaces only one chloride in the absence of Tl+. Treatment of 1 with NaBH4 produces RuH(η2-BH4)(ttp), which undergoes substitution reactions to yield the cationic hydrido ligand complexes [RuH(L)(L′)(ttp)]Y (L = P (OCH3)3, PF3, CO, NCCH3; L′ = P(OCH3)3, NCCH3, CO; Y = BF4) by treatment with HBF4 and the appropriate ligands. If the ligand substitution reactions are performed in basic solutions, the ligand dihydrido complexes RuH2(L)(ttp) result. The ruthenium(0) complexes Ru(CO)2(ttp), 10, and Ru(CO)2(Cyttp), 11, can be prepared by (i) Na/Hg reduction of 1 or 2, (ii) reduction of the dicarbonyl complexes [Ru(CO)2(ttp)][BF4]2 or [RuH(CO)2(ttp)]BF4, or (iii) triphosphine substitution of Ru3(CO)12. The complex Ru(CO)2(Cyttp), 11, undergoes oxidative addition reactions with halogens and acids to form the cationic, six-coordinate ruthenium(II) dicarbonyls [RuX(CO)2(ttp)]Y (XY = HCl, HBr, HBF4, Cl2, Br2) and with molecular oxygen to give Ru(CO3)(CO)(Cyttp). The preparation and characterization of these new ruthenium(II) and ruthenium(0) triphosphine complexes are reported, and structures are proposed on the basis of their conductivity, elemental compositions, and infrared, 1H, 31P, and 19F NMR spectroscopy.
