Metal heterometallic

Heterometallic ferrocene-based transition metal compounds. P. N. Gaponik, A. I. Lesnitovich and Y. G. Orlik, Russ. Chem. Rev. (Engl. Transl), 1983,52,168-183 (293). 

Selective metal-ligand interactions in heterometallic transition metal clusters. E. Sappa, A. Tiripio-chio and P. Braunstein, Coord. Chem. Rev., 1985, 65, 219 (218). 

Metal AlkoxidesandDiketonates, and Double-Metal Alkoxides/ Heterometallic Alkoxides, sections in Gelest Inc. Handbook, Milwaukee, WI (1995)... 

Homometallic and Heterometallic Transition Metal Allenyl Complexes Synthesis,... 

Ligand activation and transformation at heterometallic clusters have been reviewed, but few examples of very mixed -metal clusters effecting these... 

Very few reports concerning transformations of ligands with other donor atoms exist (Table V). P—H activation at secondary phosphines is the most common motif, with the metal-metal bonds at the heterometallic faces stabilizing the resulting fragments in each case (Figs. 31. 32, 33).In the formation of both... 

Reactions of clusters with mononuclear or dinuclear metal complexes frequently provide a method of expanding the metal core nuclearity under controlled conditions. The majority of medium- and high-nuclearity homometallic clusters has been prepared from lower-nuclearity cluster precursors by thermolyses ("heat-it-and-hope ) reactions. This is less true of the heterometallic clusters in this... 

The electrochemical behavior of heterometallic clusters has been reviewed clsewbcre."" The interest in examining clusters stems from their potential to act as "electron sinks " in principle, an aggregate of several metal atoms may be capable of multiple redox state changes. The incorporation of heterometals provides the opportunity to tune the electrochemical response, effects which should be maximized in very mixed"-metal clusters. Few very mixed -metal clusters have been subjected to detailed electrochemical studies the majority of reports deal with cyclic voltammetry only. Table XII contains a summary of electrochemical investigations of "very mixed"-metal clusters. 

The qualitative stabihty constants of metalloporphyrins are summarized in Table 1. The metals classified in class I produce the most stable metalloporphyrins and the demetalation reaction does not proceed smoothly even under concentrated sulfuric acid condition. The incorporated metals classified in classes 11 and III are removed using mild acids such as hydrochloric acid. Calcium classified in class V is removed by (the pH of) water. The mixed cyclization reactions afford the heterometalated CPO, and the acid treatment of the CPO obtained produces the CPO containing 2HPor moiety. Further treatment of the metal salt classified in a class lower than that of the unremoved metal(s), which is classified in a class higher in Table 1, produces another heterometalated CPO. Representative examples are summarized in Fig. 5 [25]. The initial cyclization reaction is carried out by using Ru (CO)Por 6, the metal of which is classified in class 1, and ZnPor 5, clas-... 

The thermally stable tripodal tris]amido)methalates of the group 14 element can act as metal building blocks [239, 240] in the synthesis of heterometallic systems... 

Fig. 25. Heterometallic complex of 1-methylcytosine, highlighting the nature of the metal-metal interaction involving the filled Ptn dz2 with the Pd11 dl2 v2.

There are, of course, metal-containing dendrimers that belong to more than one of the above-mentioned categories. Examples are the heptametallic dendrimer made of a central Fe(Cp)(C6Me6)+ core and coated with 6 ferrocene moieties [ 12], and the heterometallic dendrimers made of an organic core, containing up to 6 Pt(IV)-based organometallic species in the branches, and coated with up to 12 ferrocene units [13]. 

In contrast, Fe-Hg-X complexes show little tendency to form halide bridged species and less is known about complexes containing Zn. We first reported the formation of Fe-Si-O-M four membered ring systems with soft metals M = Ag, Rh, Pd, and Pt, and then prepared bimetallic complexes with more oxophilic metals in order to better understand the conditions for the occurrence of this unusual (t-alkoxy-silyl bridging mode. We have expanded our studies on Cd-containing complexes [3b-d] to Group 13 elements and we report here about the synthesis and reactivity of new, stable heterometallic Fe-M (M =... 

Indium and gallium coordination compounds containing phosphine ligands have recently aroused interest for their widespread application as intermediates in the preparation of the Group 13 - Group 14 semiconductors [4], Since the early reports about compounds with transition metal-indium bonds [51, relatively little research has been reported in this field. However there is a growing interest in the coordination chemistry and structural features of heterometallic indium [6] and gallium complexes [7] which are also attractive as potential precursors of new materials with particular properties. 

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