| Abstract
| - Reaction of bis(2-aminoethyl)(3-aminopropyl)amine with C6F6 and K2CO3 in DMSO yields unsymmetrical{(C6F5)HNCH2CH2}2NCH2CH2CH2NH(C6F5) ([N3N]H3). The tetraamine acts as a tridentate ligand in complexes ofthe type H[N3N]Re(O)X (X = Cl 1, Br 2) prepared by reacting Re(O)X3(PPh3)2 with [N3N]H3 and an excess of NEt3in THF. Addition of 1 equiv of TaCH(CMe2Ph)Br3(THF)2 to 1 gives the dimeric compound H[N3N]ClReOReBrCl[N3N]H (3) in quantitative yield that contains a Re(V)ORe(IV) core with uncoordinated aminopropyl groups ineach ligand. Addition of 2 equiv of TaCH(CMe2Ph)Cl3(THF)2 to 1 leads to the chloro complex [N3N]ReCl (4) withall three amido groups coordinated to the metal, whereas by addition of 2 equiv of TaCH(CMe2Ph)Br3(THF)2 to 2the dibromo species H[N3N]ReBr2 (5) with one uncoordinated amino group is isolated. Reduction of 4 under anatmosphere of dinitrogen with sodium amalgam gives the dinitrogen complex [N3N]Re(N2) (6). Single-crystal X-raystructure determinations have been carried out on complexes 1, 3, 5, and 6.
- Rhenium complexes that contain a C6F5 substituted unsymmetrical tren-based ligand have been synthesized and structurally characterized. Stepwise reduction of H[N3N]Re(O)X (X = Cl, Br) affords initially the unusual mixed-valent complex H[N3N]ClReOReBrCl[N3N]H possessing interesting structural features. Further reactivity involves the formation of rare rhenium(IV) amido compounds of the type [N3N]ReX or H[N3N]ReX2 with the ligand being tetradentate or tridentate depending on the nature of X. Reduction under dinitrogen yields the dinitrogen complex [N3N]Re(N2).
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