Chromium complexes mixed-ligand

Mixed cobalt/chromium complexes of the symmetrical 1 2 type in which each ligand contains a low-reactivity system linked to the coupling component (section 5.5.2) have been widely used for continuous dyeing and printing. They offer high light fastness and the... 

The chromium(II) hydride [CrH2 P(OMe)3 s] is fluxional and the seven-coordinate structure (20) is likely from an analysis of the 31P and XH NMR spectra (Table 21).125 Some mixed ligand complexes with organic isocyanides are given in Table 3. 

Table 2 Photochemistry of Mixed-ligand Chromium(III) Complexes upon Irradiation into the Lowest Quartet Ligand...

The alcoholysis of derivatives that do not initially contain alkoxide ligands is of special importance for the preparation of alkoxide halids. It is also an efficient synthetic route to mixed-ligand complexes of chromium [538, 523, 1189] ... 

Mixed donor tridentate [NPS] ligated derivatives, chromium(III) complexes, 5, 370 Mixed iridium carbonyl dimers, preparation, 7, 289 Mixed isonitrile acetylides, liquid crystals, 12, 281 Mixed isonitrile phenyl complexes, liquid crystals, 12, 282 Mixed ligand triangular Pt carbonyl clusters, characteristics, 8, 411... 

Infrared and electronic spectra confirm the nature of the hexa-N-thiocyanatometallate anions of chromium(III) (293, 639, 647, 656, 663, 665) and molybdenum(III) (293, 489, 647, 663, 664), and molyb-denum(II) (534) a variety of salts have been reported containing these anions (see the foregoing and also Refs. 30 and 528). Infrared spectra and magnetic measurements have been used to characterize [M(NCS)e] (M = Mo, W) and [W(NCS)g] (386). A large number of mixed-ligand thiocyanate complexes of chromium(III) have been reported, and many of these are of the type M[Cr(CNS)4L2], similar to the original Reinecke s salt where L = NH3. 

Gnmwald-Winstein analysis, 505 Chromium(III) complexes doublet excited states reactions, 400 emission rules, 395 ligand field states reactivity, 397 magnetic behavior, 272 mixed-ligand reactivity, 398 nitrito... 

We have also expanded our studies to include chromium(III) systems. However, for the chromium centers we have chosen the more volatile tri-fluoro (tfa") and hexafluoro (hfa ) derivatives of 2,4-pentanedione. Since the fluorinated derivatives are deactivated relative to the electrophilic attack used in these polymerizations, the Cr(acac)2(tfa) mixed ligand complex has been used initially to obtain polymeric products with sulfur halides. Whereas the intrinsic viscosity of one of the polymers so obtained was 0.17 dL/g, the GPC results suggest only oligomeric products. 

Mixed-ligand complexes of chromium(III) also undergo photoaquation reactions. In general, two or more photoreactions occur simultaneously, and the predominant product from the photochemical reaction may be different from the product that is obtained under thermal conditions. An example of such difference in regioselectivity is observed with the halo complexes CrX(NH3)s. Under thermal conditions, aquation of the halide ion (X") is the preferred pathway ... 

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