A luminescent molecular rectangle [Au(4)(micro-PAnP)(2)(micro-bipy)(2)](OTf)(4) (1.(OTf)(4)) (PAnP = 9,10-bis(diphenylphosphino)anthracene, bipy = 4,4'-bipyridine, X = NO(3)(-) or OTf(-)), synthesized from the self-assembly of the molecular "clip" Au(2)(micro-PAnP)(OTf)(2) and bipy, shows a large rectangular cavity of 7.921(3) x 16.76(3) A. The electronic absorption and emission spectroscopy, and electrochemistry of the metallacyclophane, have been studied. The 1(4+) ions are self-assembled into 2D mosaic in the solid state via complementary edge-to-face interactions between the Ph groups. (1)H NMR titrations ratify the 1:1 complexation between 1(4+) and various aromatic molecules. Comparing the structures of the inclusion complexes indicates an induced-fit mechanism operating in the binding. The emission of 1(4+) is quenched upon the guest binding. The binding constants are determined by both (1)H NMR and fluorescence titrations. Solvophobic and ion-dipole effects are shown to be important in stabilizing the inclusion complexes.
Dicyclometalated complexes syn-and anti-[Pt 2 (L) 2 (PAnP-H 2 )](OTf) 2 (Pt 2 ) are synthesized from reactions of 9,10-bis(diphenylphosphino)anthracene (PAnP) and Pt(L)(OTf) 2 (L ) diphosphines, OTf ) CF 3 SO 3 ). Because of metal perturbation on the electronic structure of the anthracenyl ring, the 1 B 2u r 1 A g transition, which is forbidden in anthracene, is observed in the electronic spectra of Pt 2 . The complexes display fluorescence arising from the ligand-centered S 1 excited state. No significant heavy atom effect is observed in the Pt 2 complexes. To understand the effect of the number of Pt ions on the extent of perturbation, a mononuclear analogue, [Pt(dppe)(PAn-H)]ClO 4 (PAn ) 9-diphenylphosphinoanthracene), is prepared and its spectroscopy studied.
Reactions of 9,10-bis(diphenylphosphino)anthracene (PAnP) and AgX (X = OTf-, ClO4-, PF6-, and BF4-) led to luminescent Ag-PAnP complexes with rich structural diversity. Helical polymers [Ag(mu-PAnP)(CH3CN)X]n (X = OTf-, ClO4-, and PF6-) and discrete binuclear [Ag2(mu-PAnP)2(CH3CN)4](PF6)2, trinuclear [Ag3(mu-PAnP)3 supersetBF4](BF4)2, and tetranuclear [Ag4(mu-PAnP)4 superset(ClO4)2](ClO4)2 metallacycles were isolated from different solvents. The tri- and tetranuclear metallacycles exhibited novel puckered-ring and saddlelike structures. Variable-temperature (VT) 31P{1H}-NMR spectroscopy of the complexes was solvent dependent. The dynamics in CD3CN involve two species, but the exchange processes in CD2Cl2 are more complicated. A ring-opening polymerization was proposed for the exchange mechanism in CD3CN.
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