58298-10-5Relevant academic research and scientific papers
The structural characterization of Re2Cl4(μ-dcpm)2 (dcpm = Cy2PCH2PCy2) and a new crystallographic form of Re2Cl4(μ-dppm)2 (dppm = Ph2PCH2PPh2)
Bera, Jitendra K.,Fanwick, Phillip E.,A. Walton, Richard
, p. 138 - 142 (2000)
The single crystal X-ray structures of the triply bonded complexes Re2Cl4(μ-dcpm)2 (1) (dcpm = Cy2PCH2PCy2) and a new crystal form of Re2Cl4(μ-dppm)2 (2) (dppm = Ph2PCH2PPh2) have been determined and are compared with literature data for other complexes of this type. Complexes 1 and 2 both possess staggered rotational geometries. Complex 1 has Re-Re distances of 2.2256(4) and 2.2267(4) A? for two crystallographically independent molecules. Complex 2 also has two independent molecules in the asymmetric unit, one of which is normal with Re-Re = 2.2497(4) A?, whereas the other exhibits a twofold orientational disorder for the Re-Re unit (distances 2.2368(5) A? and 2.231(4) A? for the major (90%) and minor (10%) forms respectively).
Assemblies of multiply bonded [Re2]n+ cores possessing bond orders of 3 or 3.5 that are linked by dicarboxylate bridges
Bera, Jitendra K.,Clerac, Rodolphe,Fanwick, Phillip E.,Walton, Richard A.
, p. 2168 - 2172 (2002)
An earlier study describing the exchange of the μ-acetato ligands of Re2(μ-O2CCH3)Cl4(μ-dppm) 2 (1) and cis-Re2(μ-O2CCH3)2Cl 2(μ-dppm)2 (2) by dicarboxylic acids has been expanded to include reactions with the monocarboxylic acid isonicotinic acid, and the dicarboxylic acids adipic acid, 4,4′-biphenyldicarboxylic acid, fumaric acid, trans-1,4-cyclohexanedicarboxylic acid and 1,1′-ferrocenedicarboxylic acid. Further examples of complexes that are "dimers-of-dimers" and triangular supramolecular assemblies involving retention of the basic electronic and molecular structures of the dirhenium units present in 1 and 2 have been obtained. In addition, the dirhenium complexes Re2(μ-O2CC6H4N)Cl4 (μ-dppm)2 (7) and cis-Re2(μ-O2C6H10CO 2Et)2Cl2(μ-dppm)2 (11) have been isolated, as well as the trimetallic complex cis-Re2Cl2(μ-dppm)2[(μ-O2 CC5H4)2Fe] (14) that is formed from the reaction of 2 with (C5H4CO2H)2Fe. The crystal structures of 7, 11 and 14 are reported.
Structural, electronic and magnetic properties of metal-metal bonded dinuclear rhenium complexes bridged by organocyanide acceptor ligands
Bartley, Stuart L.,Bazile Jr., Mervin J.,Clerac, Rodolphe,Zhao, Hanhua,Ouyang, Xiang,Dunbar, Kim R.
, p. 2937 - 2944 (2003)
The syntheses, spectroscopic properties, redox chemistry, and solid-state structures of products obtained from the reaction of Re2Cl4(dppm)2 (dppm = bis(diphenylphosphino) methane) with the polycyano acceptors TCNQ (7,7,8,
Isomerization in Metal-Metal Bonded M2L10 Systems Involving Cis and Trans Sets of Bis(diphenylphosphino)methane Ligands
Cutler, Ann R.,Derringer, Daniel R.,Fanwick, Phillip E.,Walton, Richard A.
, p. 5024 - 5034 (2007/10/02)
The reactions of the dirhenium(III) complexes Re2(O2CR)4X2 (R = CH3, C2H5, C6H5; X = Cl, Br), Re2(O2CR)2X4L2 (R = CH3, C2H5; X = Cl, Br; L = H2O, 4-methylpyridine, DMF, DMSO), and (n-Bu4N)2Re2X8 (X = Cl, Br) with Ph2PCH2PPh2 (abbreviated dppm) or, in the case of (n-Bu4N)2Re2X8, Ph2CH2PPh2/acetate mixtures affords the reduced complexes Re2(O2CR)X4(dppm)2 and cis- and trans-Re2(O2CR)2X2(dppm)2 depending upon the choice of reaction conditions.The thermolysis of Re2(O2CR)X4(dppm)2 provides a high yield synthetic route to Re2X4(dppm)2 (X = Cl, Br), a procedure that can be adapted to produce Re2I4(dppm)2 directly from Re2(O2CCH3)2I4.nH2O.The cis and trans isomers of the triply bonded dirhenium(II) compounds Re2(O2CR)2X2(dppm)2 can be oxidized to paramagnetic cis-PF6 and trans-PF6 by 5-C5H5)2Fe>PF6 and (C7H7)PF6, respectively.The structures of representative members of these groups of new complexes have been established by X-ray crystallography, viz., Re2(O2CCH3)Cl4(dppm)2.2(CH3)2CO (1), cis-Re2(O2CCH3)2Cl2(dppm)2 (2), and trans-PF6.CH2Cl2 (3).Complex 1 crystallizes in the monoclinic space group P21/c with the following unit cell dimensions: a = 12.720 (2) Angstroem, b = 35.593 (5) Angstroem, c = 9.405 (2) Angstroem, β = 104.36 (1) deg, V = 5610 (3) Angstroem3, and Z = 4.The structure was refined to R = 0.036 and Rw = 0.055 for 5822 data with F2 > 3.0?(F2).The structure contains symmetrically bridging acetate and dppm ligands and is based upon an eclipsed M2L10 geometry, with two axial and two equatorial Re-Cl bonds.The Re-Re distance is 2.300 (1) Angstroem, which is in accord with the presence of a Re-Re bond of order 3.5.The unit cell dimensions for complexes 2 and 3, which crystallize in the monoclinic space groups P21/c and C2/c, respectively, are as follows: for 2, a = 14.634 (6) Angstroem, b = 15.190 (5) Angstroem, c = 24.281 (6) Angstroem, β = 107.24 (3) deg, V = 5155 (6) Angstroem3, and Z = 4; for 3, a = 22.853 (5) Angstroem, b = 18.712 (3) Angstroem, c = 14.236 (4) Angstroem, β = 107.48 (2) deg, V = 5807 (4) Angstroem3, and Z = 4.The structure of 2 was refined to R = 0.045 and Rw = 0.061 for 4468 data with F2 > 3.0?(F2), whereas for 3 the refinement gave R = 0.034 and Rw = 0.049 for 2936 data with F2 > 3.0?(F2).Both complexes contain pairs of bridging acetate and dppm ligands and axial Re-Cl bonds.In 2 the pairs of acetate (and dppm) ligands are cis to one another, while they assume a trans disposition in 3.The Re-Re distance is 2.315 (1) Angstroem in 2 and 2.275 (1) Angstroem in 3.
Structural characterization of the triply bonded dirhenium(II) complexes Re2Cl4(μ-Ph2PCH2PPh 2)2 and α-Re2Cl4(Me2P(CH2) 2PMe2)
Barder, Timothy J.,Cotton, F. Albert,Dunbar, Kim R.,Powell, Gregory L.,Schwotzer, Willi,Walton, Richard A.
, p. 2550 - 2554 (2008/10/08)
The complexes Re2Cl4(LL)2, where LL are the bidentate ligands Ph2PCH2PPh2 (dppm) (1) and Me2P(CH2)2PMe2 (dmpe) (2), which both possess the electronic configuration σ2π4δ2δ*2 and thus formally a metal-metal triple bond, have been structurally characterized by X-ray crystallography. Re2Cl4(dppm)2 (1): Re2Cl4P4C50H44; monoclinic, P21/n; a = 11.647 (3) A?, b = 12.849 (4) A?, c = 38.691 (9) A?, β= 85.96 (2)°, V = 5776 (43) A?3, Z = 4. The molecule has two dppm molecules spanning the Re-Re bond. The two fused five-membered rings assume twist-boat conformations, leading to a completely staggered arrangement of the substituents on the two rhenium atoms. The average Cl-Re-Re-Cl torsion angle is 56 [1]°, and the Re-Re bond length is 2.234 (3) A?. Re2Cl4(dmpe)2·CH3OH (2) was isolated and crystallized as the α isomer, viz., with the dmpe ligands chelating. The crystallographic parameters are as follows: Re2Cl4P4OC13H36; orthorhombic, Ccma (nonstandard setting of Cmca); a = 11.595 (2) A?, b = 14.475 (2) A?, c = 14.925 (2) A?, V = 2505 (1) A?, Z = 4. The dimetallic unit has a Re-Re bond length of 2.264 (1) A and an eclipsed conformation with the geminal chlorides in a cis configuration. The five-membered chelate rings have envelope conformations.
