Ruthenium phenanthroline derivative

Optical sensors for oxygen are among the few sensors, which have found practical application for process-monitoring and clinical diagnostics. They are generally based on compounds such as platinum porphyrins or ruthenium phenanthroline derivatives (Table 17) which show a decrease in luminescence upon exposure to molecular oxygen15. 

A correction has been published - to the structure of a 4, 7-diphenyl-l, 10-phenanthroline-derived ligand in a ruthenium (II) complex described in last year s Report [see structure (193) in ref. 132]. The amendment, involving positional substitution on the phenyl rings, in no way compromises the essential results reported. A series of mixed-ligand complexes of Ru(II), in which the ligands used were 2, 2 -bipyridyl, 1, 10-phenanthroline, 4, 7-diphenyl-l, 10-phenanthroline,... 

Castellano et al. [188] have described the photophysical properties of ruthe-nium(ii) tris(l,10-phenanthroline) derivatives having either one or three pyrene units attached at the 5-position, complex 50 (Fig. 2.25). These latter systems show phosphorescence only from the MLCT state of the metal complex. The triplet lifetimes are much enhanced relative to the parent complex, with the dyad and triad, respectively, displaying phosphorescence lifetimes of 24 and 148 ps in deoxy-genated acetonitrile at room temperature. At the time, this was the longest lifetime to be assigned to the MLCT triplet state of a ruthenium(II) poly(pyridine) complex. 

Thus one can expect that the copper complexes with 2,2 -bipyridine, 1,10-phenanthroline, and their derivatives are successfully applied to asymmetric photoreactions, as with chiral ruthenium(II) complexes, if the optically active moiety is introduced to the ligand, as discussed above (see introduction). 

Since the copper complexes, [Cu(NN)2]+ and [Cu(NN)(PR3)2]+ (NN = 1,10-phenanthroline, 2,2 -bipyridine, and their derivatives) were applied to stoichiometric and catalytic photoreduction of cobalt(III) complexes [8a,b,e,9a,d], one can expect to perform the asymmetric photoreduction system with the similar copper(l) complexes if the optically active center is introduced into the copper(I) complex. To construct such an asymmetric photoreaction system, we need chiral copper(I) complex. Copper complex, however, takes a four-coordinate structure. This means that the molecular asymmetry around the metal center cannot exist in the copper complex, unlike in six-coordinate octahedral ruthenium(II) complexes. Thus we need to synthesize some chiral ligand in the copper complexes. 

A series of ruthenium (II) diimine complexes containing oxa-thiacrown derived from 1,10-phenanthroline have been synthesized and characterized <2007IC720>. The crystal stmctures of [Ru(bpy)2200](PF6)2, [Ru(bpy)2201](ClC>4)2, [Ru(bpy)2202](C104)2 have been determined. The luminescence properties of [Ru(bpy)2200](C104)2 were found to be sensitive and selective toward the presence of Hgz+ ions in an acetonitrile solution. 

The carbonylation of allylic compounds by transition metal complexes is a versatile method for synthesizing unsaturated carboxylic acid derivatives (Eq. 11.22) [64]. Usually, palladium complexes are used for the carbonylation of allylic compounds [65], whereas ruthenium complexes show characteristic catalytic activity in allylic carbonylation reactions. Cinnamyl methyl carbonate reacts with CO in the presence of a Ru3(CO)i2/l,10-phenanthroline catalyst in dimethylformamide (DMF) to give methyl 4-phenyl-3-butenoate in excellent yield (Eq. 11.23) [66]. The regioselectivity is the same as in the palladium complex-catalyzed reaction. However, when ( )-2-butenyl methyl carbonate is used as a substrate, methyl ( )-2-methyl-2-butenoate is the major product, with the more sterically hindered carbon atom of the allylic group being carbo-nylated (Eq. 11.24). This regioselectivity is characteristic of the ruthenium catalyst [66]. 

Complexes of ruthenium(ll) and methyl-substituted derivatives of 1,10-phenanthroline have been suggested as iodine fluorescent indicators under conditions where a starch does not function, such as highly acid, dilute, or colored solutions. 

Electropolymerization of 4-Vinylpyridine Complexes. Investigations of Structural and Electronic Influences on Thin Film Formation. The recent discovery of the reductive polymerization of complexes containing vinylpyridyl ligands (lg), such as Ru -(bpy)2(vpy)22+ has led to the preparation of homogeneous thin layers of very stable electroactive polymers. This method has been extended to 4-vinyl-4 -methyl-2,2 -bipyridine (lg, 21a) and 4-vinyl-l,10-phenanthroline (21b) on both ruthenium and iron. In the following section we discuss our results on thin films derived from the polymerizable ligands BPE and the trans-4 -X-stilbazoles, (4 -X-stilb X - Cl, OMe, CN and H). 

Baker, G. A. Wenner, B. R. Watkins, A. N. Bright, F. V., Effects of processing temperature on the oxygen quenching behavior of tris(4,7,-diphenyl-l,10,-phenanthroline) ruthenium (II) sequestered within sol-eel-derived xerogel films. Journal of Sol-Gel Science and Technology... 

Two examples of low temperature, catalytic, methane oxidation by hydrogen peroxide should be included in this section. The first involves conversion to methanol using cis-[Ru(2,9-dimethyl-l,10-phenanthroline)(solvent)2](PF6)2 as the catalyst [39]. A ruthenium-oxo species has been proposed as the C-H activating species. In the second report, conversion of methane to methyl hydroperoxide is claimed [40]. The catalyst is a combination of [NBuJ V03 and pyrazine-2-carbox-ylic acid. While the mechanism is uncertain, the actual oxidant is believed to be dioxygen with HO derived from hydrogen peroxide acting as the initiator. 

Phenanthroline and extraction of the formed complex into 1,2-dichloroethane was used to determine iron in phosphate luminophores [5]. The method using 1,10-phenanthroline and FIA system has been described [6]. The use of 4,7-diphenyl-1,10-phenanthroline as chromogenic reagent allows simultaneous determination of iron (and ruthenium) as ternary complexes by extractive (1,2-dichloroethane) zero-order and second derivative spectrophotometry [7]. Iron (Co and Cu) in cobalt magnetic alloys were determined by using... 

As discussed above, the tris(phenanthroline)ruthenium(II) complexes offer a novel spectroscopic probe of nucleic acids, since their luminescence is increased upon intercalation into the double helix. As a result the complexes provide a simple luminescent stain for DNA in fluorescent microscopy experiments. More interesting, perhaps, is the conformational selectivity of derivatives of tris(phenanthro-... 

The variety of studies conducted with tris(phenanthroline)metal complexes and DNA perhaps most easily illustrate this point (16). Tris(phenanthroline) complexes of ruthenium(II) and its derivatives possess an intense luminescent metal-to-ligand charge-transfer state that is... 

Ru(TMP)3] A distinctive characteristic of the A conformation is its shallow and wide minor-groove surface. Tris(phenanthroline)metal complexes bind to DNA both through intercalation in the major groove and through a surface-bound interaction in the minor groove (18-20) (see above). It is this surface-bound interaction that has been exploited in the construction of a complex, a derivative of tris(phenanthroline)ruthenium(II) that selectively targets A-form helical structures (30, 75). 

Bipyridine, phenanthroline, and related ligands are classics of redox- and photochemistry and are found in many applications. A very useful compilation of references, synthesis, UV-absorption spectroscopy, and electrochemical data of ruthenium tris-bipyridyl complexes and derivatives has been published [72]. Also compiled in this account is a... 

To avoid this complication, the equilibrium constant for the reaction of with the tetraamine(phenanthroline)ruthenium(III) cation was derived from independent kinetic studies of the forward and reverse rate constants, specifically taking into consideration secondary reactions of SO, [64]. In this work, the value °=0.72 V was derived. Based on the thoroughness of this study, this value is recommended. 

As commented before, decomplexations of the arene ligands are usually performed by simple exposure of acetonitrile solutions of the complexes to UV light. Nevertheless, in the case of electron-rich ruthenium derivatives, the process is not really efficient under these conditions and requires the addition of 1,10-phenanthroline, which acts as a competing ligand for the organometallic moiety. This methodology has been employed, for example, for the demetallation of 43 (Figure 7). ... 

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