These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Rhomboidal heterometallic alkynyl based Pt2Cd2 clusters: structural, photophysical, and theoretical studies. Author: Berenguer JR, Fernández J, Gil B, Lalinde E, Sánchez S. Journal: Inorg Chem; 2010 May 03; 49(9):4232-44. PubMed ID: 20380383. Abstract: Reactions between [Pt(C[triple bond]CR)(4)](2-) (R = Tol a, C(6)H(4)OMe-4 b, C(6)H(4)OMe-3 c) and Cd(2+) depend on the media and the alkynyl substituent, leading to the formation of yellow tetranuclear solvate complexes [Pt(C[triple bond]CR)(4)Cd(acetone)](2) 1a,b(acetone)(2) and [Pt(C[triple bond]CC(6)H(4)OMe-3)(4)Cd(dmso)](2) 1c(dmso)(2) or white polymeric solvate-free species [Pt(C[triple bond]CR)(4)Cd](x) 1'a-c. Treatment of 1a,b(acetone)(2) or 1'a-c with N-donor ligands affords a series of tetranuclear clusters [Pt(C[triple bond]CR)(4)CdL](2) (L = py; 2a-c. R = Tol; L = NC(5)H(4)CH(3)-4 3, NC(5)H(4)CF(3)-4 4, pzH 5). X-ray crystallographic studies reveal that, in the tolyl complexes (2a, 4, and 5), the Cd-L(2+) unit is closely bonded to one Pt-C(alpha)(acetylide) bond (Pt-Cd = 2.7, Cd-C(alpha) approximately 2.48 A), and the resulting "Pt(C[triple bond]CTol)(4)CdL" unit dimerizes by two additional eta(2)-Cd-acetylide and a weaker Pt...Cd bonding interaction leading to a planar unsymmetrical rhomboidal metal core. By contrast, the m-methoxyphenyl derivatives (2c, 1c(dmso)(2)) form symmetrical Pt(2)Cd(2) cores, with each Cd bonded (coordination number, C.N. = 5) to the incoming ligand (pyridine 2c, dmso 1c(dmso)(2)) and four Pt-C(alpha) bonds (Pt-Cd approximately 2.85; Cd-C(alpha) 2.470(10)-2.551(5) A) of different Pt(II) fragments. Evidence of ligand dissociation was found for the solvate (1a,b(acetone)(2), 1c(dmso)(2)) and NC(5)H(4)CF(3)-4 (4) derivatives by NMR and UV-vis absorption spectra. All tetranuclear aggregates exhibit bright blue to green luminescence in the solid state. Time-dependent density functional theory (TD-DFT) calculations were performed to shed light on the nature of the electronic transitions. In the solvate 1a,b(acetone)(2) and 1c(dmso)(2), emissions have been assigned to a platinum-alkynyl to cadmium charge transfer ((3)MLM'CT), mixed with some intraligand (3)IL(C[triple bond]CR) character. In the imine derivatives 2-5, they are suggested to come from an excited state of large Pt(d)/piC[triple bond]CR-->pi*(imine) MLL'CT character, mixed with some Pt(d)/pi(C[triple bond]CR)-->Pt(2)Cd(2)/pi*C[triple bond]CR (ML'M'CT) contribution.[Abstract] [Full Text] [Related] [New Search]