REACTIVITY OF RHENIUM(V) COMPLEXES CONTAINING DIFFERENT CORES SUCH AS [REO]3+, [RENR]3+ AND [REN]2+ TOWARD BIS(DIPHENYLPHOSPHINO)METHANE - SYNTHESIS AND CRYSTAL-STRUCTURES

The complexes fac-[ReOCl3(dppm-P,P')] (1a), mer-[ReOCl3(dppm-PP')] (1b), mer-[ReCl3(dppm-P,P')(dppom-P)] (2), [ReCl4(dppom-P,O)] (3) and mer-[ReCl3(dppm-P,P')PPb3] (4) (dppm = Ph2PCH2PPh2, dppom = Ph2PCH2P(= O)Ph2) were obtained by reaction of [ReOCl3(PPh3)2] or [AsPh4][ReOCl4] and dppm under different experimental conditions. Complex lb is probably obtained via the intermediate formation of complexes 2 or 4. The complexes fac-[Re(NCH3)C]3(dppm-P,P'] (5), trans-[ReNCl2(dppm-P)PPh3] (6) and [ReNCl(dppm-P,P')2]Cl (7) were also obtained starting from [Re(NCH3)Cl3(PPh3)2] and [ReNCl2(PPh3)2], respectively. The structures of la and 3 were determined by X-ray crystallography. Compound la is monoclinic, space group P2(1)/c, with a = 11.156(4), b = 17.264(5), c = 14.467(5) angstrom and beta = 110.96(3)-degrees. The molecular complex is distorted octahedral. Selected bond distances (A) are: Re-O(oxide) 1.671(6), Re-Cl(trans to 0) 2.452(3), Re-Cl(trans to P) 2.365(4) and 2.373(3), Re-P 2.439(3) and 2.449(2). The P-Re-P chelation angle is 69.2(1)-degrees. Compound 3 is orthorhombic, space group Pccn, with a = 34.843(5), b = 8.242(2) and c = 19.342(4) angstrom. The molecular complex is roughly octahedral with the oxidized dppm ligand chelated through the P atom and the 0 atom of the P = O group. Selected bond distances (angstrom) are: Re-Cl(trans one other) 2.355 (mean), Re-Cl(trans to P) 2.353(3), Re-Cl(trans to 0) 2.215(5), Re-0 2.087(7). The P-Re-0 chelation angle is 80.7(2)-degrees.