185097-81-8Relevant academic research and scientific papers
Syntheses and structure of chiral metallatetrahedron complexes of the type [Re2(M1PPh3)(M2PPh 3)(μ-PCy2)(CO)7C≡CPh] (M1 = Ag, Au; M2 = Cu, Ag, Au)
Seewald, Oliver,Floerke, Ulrich,Egold, Hans,Haupt, Hans-Juergen,Schwefer, Meinhard
, p. 204 - 210 (2006)
From the reaction of Li[Re2(μ-H)(μ-PCy2)(CO) 7(C(Ph)O)] (1) with Ph3AuC≡CPh both benzaldehyde and the trinuclear complex Li[Re2(AuPPh3)(μ-PCy 2)(CO)7C≡CPh] (2a) were obtained in high yield. The complex anion was isolated as its PPh4-salt 2b. The latter reacts with coinage metal complexes PPh3M2Cl [M2 = Cu, Ag, Au] to give chiral heterometallatetrahedranes of the general formula [Re2(AuPPh3)(M2PPh3)(μ-PCy 2)(CO)7C≡CPh] (M2 = Cu 3a, Ag 3b, Au 3c). The corresponding complex [Re2(AgPPh3) 2-(μ-PCy2)(CO)7C≡CPh] (3d) is obtained from the reaction of [Re2(AgPPh3)2(μ- PCy2)(CO)7Cl] (4) with LiC≡CPh. 3d undergoes a metathesis reaction in the presence of PPh3CuCl giving [Re 2(AgPPh3)(CuPPh3)(μ-PCy2)(CO) 7C≡CPh] (3e) and PPh3AgCl. Analogous metathesis reactions are observed when 3c is reacted with PPh3AgCl or PPh 3CuCl giving 3a or 3b, respectively. The reaction of 1 with PPh 3AuCl gives benzaldehyde and Li[Re2(AuPPh 3)(μ-PCy2)(CO)7Cl] (5a) which upon reaction with PhLi forms the trinuclear complex Li[Re2(AuPPh 3)(μ-PCy2)-(CO)7Ph] (6a). Again this complex was isolated as its PPh4-salt 6b. In contrast to 2b, 6b reacts with one equivalent of Ph3PAuCl by transmetalation to give Ph 3PAuPh and PPh4[Re2(AuPPh3)(μ- PCy2)-(CO)7Cl] (5b). The X-ray structures of the compounds 3a, 3b, 3e and 4 are reported.
Stepwise Synthesis of the Functionalized Metallatetrahedron Re2(AuPPh3)2(μ-PCy2)(CO) 7X (X = Cl, Br, I)
Haupt,Schwefer,Egold,Fl?rke
, p. 184 - 188 (1997)
In THF solution the dirhenium complex Re2(μ-H)(μ-PCy2)(CO)8 (1) reacts with an equimolar amount of LiPh at-100 °C to afford after warming up to room temperature within l h the salt Li[Re2(μ-H)(μ-PCy2)(C(Ph)O)-(CO)7] (Li[2]). Through cation exchange of Li+ against PPh4+, Li[2] gives the airstable solid PPh4[2] in 86% yield. The selectivity of the LiPh attack at one of the four axial carbonyls in 1 was proved by the chiral shift reagent Eu(hfac)3 which was dissolved in a CDCl3 solution of PPh4[2]. The 1H and 31P NMR spectra show the diastereomeric resolution of the respective peaks in an integral ratio of 1:1 e.g. Δδ(μ-P) 0.43. The anion [2-] generates with 2 equiv of XAuPPh3 (X = Cl, Br, I) in THF at room temperature within 15 min under release of the leaving group PhCHO the yellow cluster complexes Re2(AuPPh3)2(μPCy2)(CO) 7(4a-c). Their precursor complex anions [Re2(μ-AuPPh3)(μ-PCy2)(CO) 7X]- (3a-c) are obtained from 1 and an equimolar amount of XAuPPh3 or from the deauration by treatment of 4a (X = Cl) with 1 equiv of LiPh via a transmetalation reaction. Such anions are isolable as salts, N(PPh3)2[3a-c]. All new cluster complexes are identified by means of 1H NMR, 31P NMR and ν(CO) IR spectroscopic measurements, Li[2] and 4a (X = Cl) additionally by means of X-ray single-crystal structure analyses. Li[2] crystallizes triclinic, space group P1?, Z = 2, a = 10.536(2) A?. b = 11.433(2) A?, c = 19.125(3) A?, α = 98.01 (1)°, β = 89.94(1)°, and γ = 112.22(1)°; 4a crystallizes monoclinic, space group P21,/c, with Z =4, a = 18.615(5) A?, b - 13.606(2) A?. c = 24.223(6) A?. and β= 105.14(2)°, The molecular structure of Li[2] shows a μ-H-, μ-P-bridged Re-Re bond of 3.1667(7) A?, the one of 4a a tetrahedrally shaped Re2Au2 core with a μ-P-bridged Re-Re edge of 3.2680(10) A?.
