88979-33-3Relevant academic research and scientific papers
Synthesis and some Reactions of Binuclear η-Cyclopentadienyl Rhodium Complexes containing Bis(diphenylphosphino)methane and Small Molecules ( CO, SO2, or SnCl2 ) as Bridging Ligands. Crystal and Molecular Structure of
Faraone, Felice,Bruno, Giuseppe,Schiavo, Sandra Lo,Bombieri, Gabriella
, p. 533 - 538 (1984)
The compound (1) was obtained from the reaction of with bis(diphenylphosphino)methane (dppm).The X-ray structure determination of (1) shows it to crystallize in the space group C2/c with unit-cell dimensions a = 23.738(7), b = 11.731(3),c = 26.883(7) Angstroem, β = 123.2(1)deg, and Z = 8.On the basis of 2809 reflections with I>/=3?(I), the stucture has been refined to R = 0.050 and R' = 0.045.The molecule consists of two rhodium atoms bridged by a carbonyl group and a dppm ligand; a terminal η-C5H5 ligand completes the co-ordination sphere of each rhodium atom.The Rh(1)-CO- Rh(2) and P(1)-CH2-P(2) fragments are folded on the same side.The cyclopentadienyl ligands are in cis position with an interplanar angle of 82.1 deg.Compound (1) reacts with SO2 to give and with SnCl2 to give .For these reactions the possible site of attack at (1) is discussed.The oxidative addition of Br2 and I2 to (1) changes the CO bonding from bridging to terminal.From the reaction with Br2 the cationic complex Br3 was isolated; in solution it releases CO to form the neutral complex .Initial oxidative addition to one rhodium atom occurs in the reaction of I2 with (1) and was isolated.Compound (1) does not react with MeI or with diphenylacetylene in diethyl ether.
Synthesis of triangular mixed-metal clusters by the addition of copper electrophiles to an electron-rich rhodium-rhodium bond. X-ray crystal structures of [Rh2(η-C5H5) 2(μ-CO)(μ-Ph2PCH2PPh 2)(μ-CuI)] and [Rh2(η-C5H5) ...
Bruno, Giuseppe,Lo Schiavo, Sandra,Rotondo, Enrico,Piraino, Pasquale,Faraone, Felice
, p. 2502 - 2507 (2008/10/08)
Full title: Synthesis of triangular mixed-metal clusters by the addition of copper electrophiles to an electron-rich rhodium-rhodium bond. X-ray crystal structures of [Rh2(η-C5H5) 2(μ-CO)(μ-Ph2PCH2PPh 2)(μ-CuI)] and [Rh2(η-C5H5) 2(μ-CO)(μ-Ph2PCH2PPh 2)(μ-AgO2CCH3)]. The new Rh2Cu mixed-metal clusters [Rh2(η-C5H5) 2(μ-CO)(μ-dppm)(μ-CuX)] (X = Cl, 2; X = I, 3; dppm = bis(diphenylphosphino)methane) have been prepared by reacting [Rh2(η-C5H5) 2(μ-CO)(μ-dppm)] (1) with CuX and have been spectroscopically characterized. The structure of 3 has also been established by X-ray crystallography. The compound crystallizes in the orthorhombic space group Pnma with a = 14.002 (2) A?, b = 18.306 (2) A?, c = 13.025 (1) A?, V = 3338.5 A?3, and Z = 4. The structure has been refined to R = 0.034 and Rw = 0.039 for the 1064 reflections with I ≥ 3σ(I). Complex 3 reacts with AgO2CCF3 to yield [Rh2(η-C5H5) 2(μ-CO)(μ-dppm)(μ-AgO2CCF3)] (4) which has been structurally characterized. Crystals of 4 are also orthorhombic of space group Pnma with a = 15.133 (2) A?, b = 18.176 (3) A?, c = 12.656 (1) A?, V = 3481.0 A?3, and Z = 4. R = 0.034 and Rw = 0.034 for the 1993 reflections with I ≥ 3σ(I). In both complexes structurally characterized the three metal atoms define a triangular cluster [in 3 Rh(1)-Rh(1′) = 2.746 (1), Rh(1)-Cu = 2.588 (2) A?; in 4 Rh(1)-Rh(1′) = 2.776 (1), Rh(1)-Ag = 2.719 (1) A?] with the Rh-Rh bond bridged by the dppm and the CO ligands. The rhodium atoms are each symmetrically capped by one η-cyclopentadienyl ligand, and the interplanar angle between the cyclopentadienyl rings can be related to the bulk of the group 11 metal. In 3 the iodine atom is bonded to copper while in 4 the trifluoroacetate group is chelated to the silver atom. The structural features of 3 and 4 have been compared with those of the other compounds of this class already reported. The results show that the formation of stable Rh2Ag and Rh2Cu triangular clusters by addition of electrophiles containing the group 11 metals to 1 requires the use of silver or copper salts of coordinating anions.
