4.7- Phenanthrolines substitution

Most importantly, the heterolytic coupling of carbonylmetal cations and anions is indicated in the treatment of tetracarbonylcobaltate(—I) with hexacarbonylrhenium(I) to afford the mixed carbonyl (65). Similarly, the treatment of Co(CO)4- with the phenanthroline-substituted tetracarbonyl-manganese(I) cation leads to the substituted heterobimetallic carbonyl (66), and the highly efficient coupling of the carbonylmanganese anion and cation yields the homodimer (67),... 

The infrared (IR) spectra of 1,10-phenanthroline, its hydrate and perchlorate in the region 600-2000 cm have been obtained, and the principal features of the spectra interpreted. Further studies on the IR spectra of 1,10-phenanthroline, " substituted 1,10-phenanthrolines, and 1,7-phenanthroline have also been reported. The IR spectrum of 4,7-phenanthroline in the region 650-900 cm has been analyzed, and the C—H out-of-plane deformation frequencies were compared with those of phenanthrene and benzo[/]quinoline. TTie IR spectra of salts of 1,10-phenanthroline have been taken, and the NH vibrations determined. - Infrared spectroscopy has been used to detect water associated with 1,10-phenanthroline and some of its derivatives on extraction into nitromethane from aqueous solution. The Raman spectrum of 1,10-phenanthroline has been compared with its IR spectrum. Recently, the Raman and IR spectra of all ten isomeric phenanthrolines were measured in solution and solid states, and the spectra were fully discussed. ... 

The synthetic methods of Equation 5 also proved good for the use of phenanthroline and substituted phenanthrolines as ligands. We were able to prepare and isolate complexes with 1,10-phenanthroline, 3,4,7,8-tetramethyl-l,10-phenanthroline, and 4,7-diphenyl-l,10-phenanthroline substituting for bipyridine. 

Main efforts have been devoted to sensitize NIR lanthanide luminescence by using d-block transition metal complexes as energy donors, but studies on sensitized visible lanthanide luminescence are relatively rare. By using a 1,10-phenanthroline-substituted /3-diketone of as... 

Suitable mechanisms have been proposed following determination of the kinetic and activation parameters for oxidation of 2-naphthol and cyclic ketones by nicotinium dichromate some a-amino acids by tripropylammonium fluorochromate " distyryl ketone by quinaldinium fluorochromate methanol by benzyltriethylammonium chlorochromate catalysed by 1,10-phenanthroline substituted benzyl alcohols by tetraethylammonium bromochromate L-cysteine by pyridinium bromochromate lactic acid and 3,5-dimethyl-2,6-diaryl piperidin-4-one oximes by pyridinium chlorochromate allyl alcohol by IDC benzophenoxime by bispyridine silver(I) dichromate and alkyl phenyl sulfides by cetyltrimethylammonium dichromate. A non-linear Hammett plot obtained for the oxidation of substituted benzyl alcohols by IDC has been attributed to the operation of substituent effect on two steps of the proposed mechanism. " Kinetic and activation parameters for oxidation of o-toluidine and of A-methyl-2,6-diphenyl piperidin-4-one oxime and its 3-alkyl derivatives by sodium dichromate have been determined and suitable mechanisms have been suggested. Micellar catalysis in the 1,10-phenanthroline-promoted chromic acid oxidation of propanol... 

Substitution of water by oxalate in [Ru(OH2)6] involves C204H attack by a dissociative exchange mechanism as the predominant pathway/ Kinetic parameters (k, AH, AS ) for 1,10-phenanthroline substitution at cw-[Ru(bipy)2(OH2)2] , determined over the temperature range 35 to 50 °C, the pH range 3.65 to 5.5, and the solvent composition range 0 to 30% ethanol, are also claimed to be consistent with dissociative activation. ... 

Colorimetric. A sensitive method for the deterrnination of small concentrations of dissolved iron is the spectrophotometric deterrnination of the orange-red tris(1,10-phenanthroline)iron (IT) complex. Other substituted phenanthrolines can be even more sensitive. Only the inon(II) complexes of these Ligands are highly colored. The sample is first treated with an excess of reducing agent. The complexes are stable from pH 2 ndash 9 and analysis preferably is done at about pH 3.5. 

Classic A/-heterocychc ligands, eg, bipyridyl (bipy), terpyridyl, imidazole, pyrazine, phenanthroline, piperazine (including alkyl- and aryl-substituted derivatives), and polypyrazol-l-yl-borates (bis, tris, and tetra), have all been found to coordinate Th(IV) chlorides, perchlorates, and nitrates. The tripodal hydrotris(pyrazolyl)borates, HBPz, have been used to stabilize organometaHic complexes (31). Bis-porphyrin Th(IV) "sandwich" complexes have been... 

Azonia substitution at a naphthalene bridgehead position gives the quinolizinium ion (16). Oxonia substitution, elsewhere, forms the 1- and 2-benzopyrylium ions (17) and (18). The two most well-known monoaza systems with three aromatie fused rings are aeridine (19), derived structurally from anthraeene, and phenanthridine (20), an azaphenanthrene. The better-known diaza systems inelude phenazine (21) and 1,10-phenanthroline (22), while systems with three linearly fused pyridine rings are ealled anthyridines, e.g. the 1,9,10-isomer (23). 

Sykes has studied a number of substituted 4,7-phenanthrolines (148). Since the ring system is symmetrical, as is also the case with the 1,10-compound, the position of quaternization is controlled by the substituents. In the first paper, 5-acetamido, -bromo, and -chloro... 

Abbreviations acac, acetylacetonate Aik, alkyl AN, acetonitrile bpy, 2,2 -bipyridine Bu, butyl cod, 1,5- or 1,4-cyclooctadiene coe, cyclooctene cot, cyclooctatetraene Cp, cyclopentadienyl Cp, pentamethylcyclopenladienyl Cy, cyclohexyl dme, 1,2-dimethoxyethane dpe, bis(diphenyl-phosphino)ethane dppen, cis-l,2-bis(di[Atenylphosphino)ethylene dppm, bis(diphenylphosphino) methane dppp, l,3-bis(diphenylphosphino)propane eda,ethylenediamine Et,ethyl Hal,halide Hpz, pyrazole HPz, variously substituted pyrazoles Hpz, 3,5-dimethylpyrazole Me, methyl Mes, mesityl nbd, notboma-2,5-diene OBor, (lS)-endo-(-)-bomoxy Ph, phenyl phen, LlO-phenanthroline Pr, f opyl py, pyridine pz, pyrazolate Pz, variously substituted pyrazolates pz, 3,5-dimethylpyrazolate solv, solvent tfb, tetrafluorobenzo(5,6]bicyclo(2.2.2]octa-2,5,7-triene (tetrafluorobenzobanelene) THE, tetrahydrofuran tht, tetrahydrothicphene Tol, tolyl. 

The standard or formal potential of ferroin can be modified considerably by the introduction of various substituents in the 1,10-phenanthroline nucleus. The most important substituted ferroin is 5-nitro-l,10-phenanthroline iron(II) sulphate (nitroferroin) and 4,7-dimethyl-1,10-phenanthroline iron(II) sulphate (dimethylferroin). The former (E° = 1.25 volts) is especially suitable for titrations using Ce(IV) in nitric or perchloric acid solution where the formal potential of the oxidant is high. The 4,7-dimethylferroin has a sufficiently low formal potential ( e = 0.88 volt) to render it useful for the titration of Fe(II) with dichromate in 0.5 JVf sulphuric acid. 

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]. 

Helquist et al. [129] have reported molecular mechanics calculations to predict the suitability of a number of chiral-substituted phenanthrolines and their corresponding palladium-complexes for use in asymmetric nucleophilic substitutions of allylic acetates. Good correlation was obtained with experimental results, the highest levels of asymmetric induction being predicted and obtained with a readily available 2-(2-bornyl)-phenanthroline ligand (90 in Scheme 50). Kocovsky et al. [130] prepared a series of chiral bipyridines, also derived from monoterpene (namely pinocarvone or myrtenal). They synthesized and characterized corresponding Mo complexes, which were found to be moderately enantioselective in allylic substitution (up to 22%). 

When the bidentate B is dipyridyl or a substituted o-phenanthroline and M is Cr, only a first-order substitution is observed... 

When M is Mo or W, the substitution reaction follows a two-term rate expression and in addition there is some replacement of the dipyridyl or 1,2-diamino-2-methyl propane but not of o-phenanthroline. The proportion of bidentate replacement to CO replacement is practically independent of the concentration... 

A stopped flow technique coupled with spectrophotometric analysis of the iron (II) complex formed has been used to investigate - the reactions of some organic complexes of iron(III) with the ion Fe ". The iron(III) was complexed with 1,10-phenanthroline, various substituted 1,10-phenanthrolines (5-methyl-, 5-nitro-, 5-chloro-, 5-phenyl-, 5,6-dimethyl-, 4,7-diphenyl-, and 3,4,7,8-tetramethyl-) and 2,2 -dipyridine, 4,4 -dimethyl-2,2 -dipyridine, and 2,2, 2"-tripyridine. The wavelengths used for the analysis lay in the region 500-552 m/i. 

Fig. 2. Relationship between the logarithms of the rate coefficients (Atj. 2) and the logarithms of the equilibrium constants (Jfi.i) for the oxidation of various substituted Fe(II)-phenanthroline complexes by Mn(III) in 1 A/ and 3 Af HCIO4 at 25.0 °C. (From Diebler and Sutin, by courtesy of The American Chemical Society.)...

SLOPES AND INTERCEPTS OF PLOTS OF (AGJi 2+LI5 l0g/)W. AG i 2 FOR OXIDATION-REDUCTION REACTIONS INVOLVING SUBSTITUTED Fe(lI)-PHENANTHROLINE COMPLEXES... 

In conforming to an expected linear free energy relationship, the Ce(lV) oxidation of various 1,10-phenanthroline and bipyridyl complexes of Ru(II) in 0.5 M sulphuric acid are consistent with the requirements of the Marcus treatment . The results for the oxidation of the 3- and 5-sulphonic-substituted ferroin complexes by Ce(IV) suggest that the ligand does not function as an electron mediator, and that the mechanism is outer-sphere in type. Second-order rate coefficients for the oxidation of Ru(phen)j, Ru(bipy)3, and Ru(terpy)3 are 5.8x10, 8,8 X 10, and 7.0 x 10 l.mole . sec, respectively, in 0.5 M H2SO4 at 25 °C a rapid-mixing device was employed. 

The next available full-shell cluster that has been investigated by MoBbauer spectroscopy was the four-shell cluster Pt309phen 3603o+io (phen = 4,7-p-C6H4S03Na substituted 1,10-phenanthroline) [17]. Its inner core consists of 147 atoms. However, since platinum is not MoBbauer-active, the cluster sample had to be irradiated with thermal neutrons to transfer a fraction of the Pt... 

Copper(I) iodide with 1,10-phenanthroline catalyzes substitution of aryl iodides by alcohols. The reaction can be done either in excess alcohol or in toluene.152... 

Some other examples of metal-catalyzed substitutions are given in Scheme 11.10. Entries 1 to 3 are copper-catalyzed reactions. Entry 1 is an example of arylation of imidazole. Both dibenzylideneacetone and 1,10-phenanthroline were included as ligands and Cs2C03 was used as the base. Entry 2 is an example of amination by a primary amine. The ligand used in this case was (V,(V-diethyl sal icyl amide. These conditions proved effective for a variety of primary amines and aryl bromides with both ERG and EWG substituents. Entry 3 is an example of more classical conditions. The target structure is a phosphodiesterase inhibitor of a type used in treatment of asthma. Copper powder was used as the catalyst. 

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