Regioselective Double Cycloplatination of 9,10-Bis(diphenylphosphino)anthracene
摘要:
Double cyclometalation of 9,10-bis(diphenylphosphino)anthracene (PAnP) by Pt(L)(OTf)(2) (L = diphosphines, OTf = CF3SO3) gives rise to the geometrical isomers syn- and anti-[Pt-2(L)(2)(PAnP-H-2)](OTf)(2) (Pt-2). The reaction is regioselective, with the syn-isomer being the kinetic product. The cyclomelation is reversible, and thermodynamic product distribution is obtained after prolonged standing. The ratio of the isomers is subject to the influence of solvents and ancillary diphosphines. Protonolysis of the Pt-C leads to a monocyclometalated intermediate. A mechanistic postulate that invokes a preferential electrophilic attack of the Pt ions at the C-H bonds of the anthracenyl ring is proposed to explain the regioselectivity.
Regio- and Stereocontrolled Reaction of Arenes with Ethyl Propiolate Catalyzed by Palladium or Platinum Complexes with a Bidentate Phosphine Ligand. An Efficient and Straightforward Synthesis of (1Z,3E)-1-Aryl-1,3-butadienes
Photoluminescent macrocyclic Pd(II) and Pt(II) dimeric complexes with Ph2P–CC–PPh2 spacer
作者:Dengfeng Xu、Hunter J Murfee、Wytze E van der Veer、Bo Hong
DOI:10.1016/s0022-328x(99)00538-0
日期:2000.2
The synthesis and characterization of macrocyclic Pd(II)/Pt(II) dimers and their monomeric precursors with diphosphine spacer Ph2P-C=C-PPh2 (C2P2) are reported. Their excited-state properties, including solvent-dependent absorption, emission and quantum yield, are studied. When the solvent polarity increases, solvatochromic absorption band shifts to higher energy, emission maximum shifts to lower energy, and quantum yield decreases. In addition, the host-guest behavior of these new inorganic macrocycles is also reported here. (C) 2000 Elsevier Science S.A. All rights reserved.
Synthesis and Electronic Spectroscopy of Luminescent Cyclometalated Platinum−Anthracenyl Complexes
作者:Jian Hu、Ronger Lin、John H. K. Yip、Kwok-Yin Wong、Dik-Lung Ma、Jagadese J. Vittal
DOI:10.1021/om700706r
日期:2007.12.1
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 = CF3SO3). Because of metal perturbation on the electronic structure of the anthracenyl ring, the B-1(2u)- <- (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)]ClO4 (PAn = 9-diphenylphosphinoanthracene), is prepared and its spectroscopy studied.