Luminescent 2-phenylbenzothiazole cyclometalated Pt and Ir complexes with chelating P^O ligands.

Two series of cyclometalated Pt and Ir complexes with general formulas [Pt(pbt){PPh(R)-κ,}] (2a-2c) and [Ir(pbt){PPh(R)-κ,}] (3a-3c), where Hpbt is 2-phenylbenzothiazol and PPh(R) is a diphenylphosphino donor functionalized deprotonated acid (R = -CHCOa, -CHSOb, CHCHCOc) are presented. The structures of 1, 2a-2c, 3a and 3b were confirmed by single X-ray diffraction analyses, and the intermolecular interactions in 2a were studied using Hirshfeld surface analysis and non-covalent interaction (NCI) methods on its X-ray structure. Their photophysical properties were investigated by absorption and emission analyses [CHCl, solid (298, 77 K) and doped polystyrene (PS) films], supported by TD-DFT calculations on 1, 2a-2c and 3a.

Investigation on Optical and Biological Properties of 2-(4-Dimethylaminophenyl)benzothiazole Based Cycloplatinated Complexes.

The optical and biological properties of 2-(4-dimethylaminophenyl)benzothiazole cycloplatinated complexes featuring bioactive ligands ([{Pt(Me N-pbt)(C F )}L] [L=Me N-pbtH 1, p-dpbH (4-(diphenylphosphino)benzoic acid) 2, o-dpbH (2-(diphenylphosphino)benzoic acid) 3), [Pt(Me N-pbt)(o-dpb)] 4, [{Pt(Me N-pbt)(C F )} (μ-PR P)] [PR P=O(CH CH OC(O)C H PPh ) 5, PR P=O{(CH CH O) C(O)C H PPh } 6] are presented. Complexes 1-6 display ILCT and metal-perturbed ILCT dual emissions. The ratio between both bands is excitation dependent, accomplishing warm-white emissions for 2, 5 and 6.

Design of Luminescent, Heteroleptic, Cyclometalated Pt and Pt Complexes: Photophysics and Effects of the Cyclometalated Ligands.

Neutral pentafluorophenyl benzoquinolinyl Pt [Pt(bzq)(HC^N-κN)(C F )] (1 a-g) complexes, bearing nonmetalated N-heterocyclic HC^N ligands [HC^N=2,5-diphenyl-1,3,4-oxadiazole (Hoxd) a, 2-(2,4-difluorophenyl)pyridine (dfppy) b, 2-phenylbenzo[d]thiazole (pbt) c, 2-(4-bromophenyl)benzo[d]thiazole (Br-pbt) d, 2-phenylquinoline (pq) e, 2-thienylpyridine (thpy) f, 1-(2-pyridyl)pyrene (pypy) g], and heteroleptic bis(cyclometalated) Pt fac-[Pt(bzq)(C^N)(C F )Cl] (2 b-g, bzq: benzo[h]quinolinyl) derivatives, generated by oxidation of 1 b-g with PhICl , are reported. The oxidation reaction of 1 a evolved with formation of the bimetallic Pt complex syn-[Pt(bzq)(C F )Cl(μ-OH)] 3. The crystal structures of 1 a,d,f, 2 b,d,e and 3 were corroborated by X-ray crystallography.

Luminescent Cycloplatinated Complexes with Biologically Relevant Phosphine Ligands: Optical and Cytotoxic Properties.

Two series of neutral luminescent pentafluorophenyl cycloplatinated(II) complexes [Pt(C^N)(CF)L] [C^N = C-deprotonated 2-phenylpyridine (ppy; a), 2-(2,4-difluorophenylpyridine (dfppy; b)] incorporating dimethyl sulfoxide [L = DMSO for 1 (1a reported by us in ref (14) )] or biocompatible phosphine [L = PPhCHCOOH (dpbH; 2), PPhCHCONHCHCOOMe (dpbGlyOMe; 3), P(CHSONa) (TPPTS; 4)] ligands have been prepared and characterized and their optical properties studied. Their cytotoxic activities against tumor A549 (lung carcinoma), HeLa (cervix carcinoma), and nontumor NL-20 (lung epithelium) cell lines, as well as the ability to interact with DNA (plasmid pBR322), were evaluated. Complexes 2 exhibit higher cytotoxicity (IC 3.

Benzothiazole-Based Cycloplatinated Chromophores: Synthetic, Optical, and Biological Studies.

Cycloplatinated complexes based on 2-(4-substituted)benzothiazole ligands of type [Pt(R-PBT-κC,N)Cl(L)] (PBT=2-phenylbenzothiazole; R=Br (1), Me N (2); L=dimethyl sulfoxide (DMSO; a), 1,3,5- triaza-7-phosphaadamantane (PTA; b), triphenylphosphine 3,3',3''-trisulfonate (TPPTS; c)) and [Pt(Br-PBT-κC)Cl(PTA) ] (3) are presented. On the basis of the photophysical data and time-dependent (TD)-DFT calculations (1 a and 2 a), the low-lying transitions (absorption and emission) were associated with ligand-center (LC) charge transfer, with minor metal-to-ligand charge transfer (MLCT), and intraligand charge transfer (ILCT) [Me N-PBT→PBT] excited states, respectively. Simultaneous fluorescence/phosphorescence bands were found in fluid solutions (and also in the solid state for 2 a), which become dominated by triplet emission bands in rigid media at 77 K.

Phosphorescent platinum(ii) alkynyls end-capped with benzothiazole units.

Symmetric trans-bis(alkynyl)bis(phosphine) Pt complexes based on the 2-phenylbenzothiazole (pbt) unit [trans-Pt(C[triple bond, length as m-dash]C-pbt)L] [L = PPh1, PEt2, 1,3,5-triaza-7-phosphaadamantane (PTA) 3] and the mixed alkynyl-cyanide anionic complex (NBu)[trans-Pt(C[triple bond, length as m-dash]C-pbt)(CN)] (4) were synthesized. The complexes have been fully characterized including X-ray crystallography for 2 and 4. All complexes display long-lived emission with moderate quantum yields (ϕ 6.

Facile Approaches to Phosphorescent Bis(cyclometalated) Pentafluorophenyl Pt Complexes: Photophysics and Computational Studies.

A convenient and general strategy for the synthesis of stable bis(cyclometalated) pentafluorophenyl Pt complexes fac-[Pt(C^N) (C F )Cl] (3 a-f) and mer-[Pt(C^N) (C F )(CN)] (4 c,d) has been developed. Complexes 3 were selectively generated by low-temperature oxidation of the cyclometalated Pt complexes [Pt(C^N)(HC^N)(C F )] 2 [prepared from cis-[Pt(C F ) (HC^N) ] (1) intermediates] with PhICl and subsequent metalation of the pendant HC^N ligand. Complexes 3 a,b were also alternatively generated by irradiation (Hg lamp, 400 W) of complexes 2 a,b, respectively, in CH Cl .