Platinum complexes 1,10-phenanthroline

In the latter comprehensive review (4), other platinum complexes, such as Pt(0) and/or Pt(II) complexes with fiillerene, maleate and fiimarate, imines, chelating carbenes, diphenylacetylene, phenanthroline, and P,N-functionalized indene, as well as new organophosphorous ligands, have been cited to catalyze hydrosilylation of alkenes and aUgmes. Also, a variety of platinum(II) complexes containing silyl and alkyl ligands have been tested in the hydrosilylation of alkenes. 

A series of chloro(methyl)platinum complexes having 2,9-dimethyl-l,10- phenanthroline are obtained as the adducts of alkenes, allene, and GO (23-27, Scheme Not only does coordination of the unsaturated molecule... 

The intercalation of platinum complexes containing bidentate or tridentate aromatic amines was first proposed for binding to tRNA and then to DNA [53]. The structures of the relevant complexes of palladium and platinum are shown in Figure 1.5 and a requisite is the presence of planar ligands such as bipyridine, terpyridine, or o-phenanthroline, which are coplanar with the coordination plane formed by the four ligand donor atoms and the metal ion. The similar pyridine derivative, [Pt(en)py2], where the pyridine Ugands are forced by nonbonded steric constraints to be out of the coordination plane, does not intercalate. 

The excited state of the complex Pt(4,7-diphenyl-1,10-phenanthroline)( 1,2-dicyano-l,2-ethylenethiolate) (Pt(dpphen)(mnt)) is oxidatively quenched by o-nitrobenzaldehyde [Eq. (3.46)], and reductively quenched by dimethylaniline [Eq. (3.47)], showing that excited state photoredox chemistry can be carried out with this series of platinum complexes " ... 

Complexes of bulky substituted phenanthrolines [Pt(N-N)LX2] (L, X both monodentate N-N, e.g. 2,9-dimethyl- 1,10-phenanthroline) can be 5-coordinate tbp when a good 7r-acceptor (e.g. C2H4) is present or 4-coordinate with monodentate phenanthrolines. Hartree-Fock calculations indicate that the 7r-acceptors reduce the electron density at platinum so that the metal can accept charge from another donor. Species of this kind may be involved in alkene hydrogenation [138]. 

The dimethylplatinum(II) complexes having chelate nitrogen ligands, [PtMe2(N-N)] (N-N = 2,2 -bipyridyl or 1,10-phenanthroline) (46) reacted with alcohols (ROH, R = Me, Et, Pr) to give hygroscopic and basic platinum(IV) complexes. 

Rate and equilibrium constant data, including substituent and isotope effects, for the reaction of [Pt(bpy)2]2+ with hydroxide, are all consistent with, and interpreted in terms of, reversible addition of the hydroxide to the coordinated 2,2 -bipyridyl (397). Equilibrium constants for addition of hydroxide to a series of platinum(II)-diimine cations [Pt(diimine)2]2+, the diimines being 2,2 -bipyridyl, 2,2 -bipyrazine, 3,3 -bipyridazine, and 2,2 -bipyrimidine, suggest that hydroxide adds at the 6 position of the coordinated ligand (398). Support for this covalent hydration mechanism for hydroxide attack at coordinated diimines comes from crystal structure determinations of binuclear mixed valence copper(I)/copper(II) complexes of 2-hydroxylated 1,10-phenanthroline and 2,2 -bipyridyl (399). 

Numerous other aromatic nitrogen compounds are known, and a significant number have been used to prepare complexes of platinum(II). Phthalazine (101) is one such compound, and the complex ds-PtCl(phthalazine)(PEt3)2 has been prepared in order to compare its fluxional properties with the phenanthroline and naphthyridine analogues. The monodentate complex is fluxional, but in this phthalazine case the orientation of the lone pairs is unsuitable for the five-coordinate intermediate required by an intramolecular process and the mechanism of exchange becomes dissociative.11 6... 

Metal complexes like lanthanide chelates (mainly europium or terbium), ruthenium phenanthrolines or bipyridyls, and platinum porphyrins can be used as fluorescent labels for biomolecules. Their long decay times are perfectly suited for a detection by time-resolved imaging, and the labeled target molecules can be used for the determination of intracellular recognition processes or for the screening of DNA and protein arrays. Ratiometric lifetime-based imaging methods in combination with sophisticated data acquisition and evaluation tools can substantially contribute to the development... 

Bauerle and coworkers have synthesized a re-conjugated catenane, utilizing Cu(I) templation and a newly developed method for acetylenic homocoupling based on the reductive elimination of platinum to generate the desired C-C bond formation (Scheme 6.16) [65,66]. The C-shaped 57 was first preorganized around Cu(I), resulting in the homoleptic bis-phenanthroline complex 58. After removal... 

Pt/Mo complexes of two cycloheptadienynes (236 and 237) have been prepared by Mo(CO)3 transfer from (ijA-p-xylene)Mo(CO)3 to 222a and 222b and by hydride reduction of the corresponding Pt/Mo complex of tropyne (235) (Scheme 34) (see Sections II,G and II,H). The platinum cycloheptadienyne complexes can be regenerated from 236 and 237 with PPh3 or phenanthroline. 

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