Cluster anions 393 allyl

It is possible to extend the synthetic prindples which were presented above to the preparation of polynuclear complexes having Cp, allyl, and CO ligands. Preliminary results from the reactions of cyclopentadienyl, allyl, and CO complexes of the transition metal halides with E(SiMc3)2 (E = S, Se, Te) indicate that MesSiQ is eliminated and a series of novel compounds are formed. The reaction between [CpFe(CO)2Br] and Se(SiMe3)2 produces a diamagnetic compound composed of the heterocubane cluster anion [Fe4Se4Br4] and two [Se Fe(CO)2Cp 3] cations (Eq. 3.52). 

Heterometallic clusters containing -allylic palladium groups have been generally synthesized by reaction of an anionic cluster with [Pd(/r-X)( -allyl)]2 (X = halide) in a reaction that resembles a ligand substitution (Equation (31)). The formal oxidation state of Pd in the product cluster is usually different from two, so the reaction can also be considered as a redox transformation Pd-Fe bimetallic clusters, " and also trimetallic Pd-Fe-Fe-Co 82 and Pd-Fe-Ru-Ru, have been prepared in this way. 

The first application of phase transfer catalysis in metal carbonyl chemistry was reported by Alper in 1977(23). It was found that metal carbonyl anions could be readily generated by this technique and used to prepare pi-allyl, cluster, and ortho-metalated complexes(24). 

The outer-sphere OAc anions can be replaced by other anions. For instance, the and PF anions readily substitute for OAc anions in an aqueous solution containing KPFft, affording the giant cluster with the idealized formula [Pdsei LeoOeoKPFeleo [Ik 16, 17]. The Pd-561 clusters exhibit a high catalytic activity in alkene acetoxylation in an AcOH solution under mild conditions (20-60 °C at 0.1 MPa). Besides reaction (1), the clusters provide the oxidative acetoxylation of propylene to allyl acetate (eq. (6)) or of toluene to benzyl acetate (eq. (7)). 

Polymer-bound rhodium clusters were used for catalytic hydrogenations of a,/3-unsaturated aldehydes to allylic alcohols. Amination of chloromethylated polystyrene with 2-(2-(dimethylamino)ethoxy)ethanol gave an amine-functionalized polymer. Using the aminated polystyrene and Rh6(CO)i6 in the presence of H2 and CO or CO and water, various a,/ -unsaturated aldehydes were chemoselectively hydrogenated to give allylic alcohols in high yields, generally >95% conversion and 80-100% selectivity, at 303 K. Under the reaction conditions, a number of anionic clusters form, which can be recovered as ions paired to the ammonium cations of the polymer. Clusters identified by... 

Since 1970 or before, chemists have relied on classical, detailed temperature-dependent line-shape analyses.Indeed, fundamental contributions to our understanding of the dynamics of fluxional metal complexes with vr-hydrocarbon ligands,tertiary phosphorus donors, as well as TT-allyl anions,all stem from these types of measurement. Their contributions to metal carbonyl dynamics and rearrangements in cluster compounds is even more pronounced, and we cite selected studies in this very large area of organometallic chemistry.For slow exchange... 

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