350045-86-2

Upstream product

• 3558-69-8 2,6-diphenylpyridine 
• 224195-09-9 (dimethyl sulfoxide)(2,6-diphenylpyridinate^(2-))platinum(II) 
• 603-35-0 triphenylphosphine 

Relevant academic research and scientific papers

Influence of Ligand and Nuclearity on the Cytotoxicity of Cyclometallated C^N^C Platinum(II) Complexes

A series of cyclometallated mono- and di-nuclear platinum(II) complexes and the parent organic ligand, 2,6-diphenylpyridine 1 (HC^N^CH), have been synthesized and characterized. This library of compounds includes [(C^N^C)PtII(L)] (L=dimethylsulfoxide (DMSO) 2 and triphenylphosphine (PPh3) 3) and [((C^N^C)PtII)2(L‘)] (where L‘=N-heterocycles (pyrazine (pyr) 4, 4,4‘-bipyridine (4,4‘-bipy) 5 or diphosphine (1,4-bis(diphenylphosphino)butane (dppb) 6). Their cytotoxicity was assessed against four cancerous cell lines and one normal cell line, with results highlighting significantly increased antiproliferative activity for the dinuclear complexes (4–6), when compared to the mononucleated species (2 and 3). Complex 6 is the most promising candidate, displaying very high selectivity towards cancerous cells, with selectivity index (SI) values >29.5 (A2780) and >11.2 (A2780cisR), and outperforming cisplatin by >4-fold and >18-fold, respectively.

π-π interactions in organometallic systems. Crystal structures and spectroscopic properties of luminescent mono-, bi-, and trinuclear trans-cyclometalated platinum(II) complexes derived from 2,6-diphenylpyridine

A series of mono- and multinuclear dicyclometalated platinum(II) complexes, namely, [Pt-(CNC)L1] [HCNCH = 2,6-diphenylpyridine; L1 = 4-tert-butylpyridine (1), 1-methyl-4,4′-bipyridinium (MQ+) hexafluorophosphate (2(PF6)), 2,6-dimethylphenylisocyanide (4), tricyclohexylphosphine (5), triphenylphosphine (7)], [Pt2(CNC)2(μ-L2)] [L2 = pyrazine (pyr; 3), bis(dicyclohexylphosphino)methane (dcpm; 6), bis(diphenylphosphino)methane (dppm; 8)], and [Pt3(CNC)3(μ3-dpmp)] [dpmp = bis(diphenylphosphinomethyl)phenylphosphine (9)], were synthesized from [Pt(CNC)dmso] (dmso = dimethyl sulfoxide). The X-ray crystal structures of 1,3·CHCl3, 4, 6·CHCl3·CH3OH·4H2O, 7, 8 (yellow form), and 8·CHCl3 (orange form) have been determined. For complex 1, the Pt(CNC) units are oriented into pairs in a head-to-tail fashion with an interplanar separation of 3.40 A?. For complex 4, dimeric π-π overlap between Pt(CNC) and phenyl moieties in a head-to-tail manner is observed, with interplanar stacking at 3.39 A?. There are two crystal forms for complex 8. Only one intramolecular Pt(CNC)-phenyl π-π interaction (separation 3.381 A?) is apparent in the yellow form. For the orange form (8·CHCl3), there are two intramolecular Pt(CNC)-phenyl π-π contacts (separations 3.115 and 3.287 A?). For 3·CHCl3, the dihedral angles between the pyrazine and the two Pt(CNC) planes are 124.0° and 130.5°, which allows the possibility for partial orbital interaction between the (5d)Pt and pπ*(pyrazine) orbitals. Complexes 1 and 4-9 display vibronically structured emission (λmax of most intense band = 508-526 nm) in 77 K methanol/ethanol (1:5, v/v) glass, which are assigned to 3IL excited states. For 1, 4-6, 8, and 9, the 77 K structureless emission at λmax 596-636 nm in methanol/ethanol glasses is assigned as ππ* excimeric in nature. These excimeric emissions are concentration-dependent for 1 and 4-6 and concentration-independent for 8 and 9. The 298 K solid emission spectra of 1, 4-6, 8, and 9 are characterized by a broad, unstructured band at λmax 566-633 nm, which red-shift in energy upon cooling to 77 K. These bands are comparable in energy to the 77 K glassy emissions and are similarly assigned. Complexes 2 and 3 show an intense absorption at λmax 410 (shoulder) and 456 nm, which are ascribed to the MLCT (5d)Pt → π*(1-methyl-4,4′-bipyridinium/pyrazine) transition, respectively. Likewise, the solid-state emissions of 2 and 3 at λmax 686 and 658 nm, respectively, are assigned as MLCT. The vapochromism of complex 8 has been investigated.