Coordination chemistry complex synthesis

The synthesis of stable complexes with transition metal-phosphorus triple bonds is of fundamental importance and opens a novel chapter of a special field of coordination chemistry. The synthesis of analogous complexes with ligands of the heavier homologues like arsenic has partially been carried out [6], while for antimony and bismuth, the elusive M=Sb and M=Bi systems have now moved within reach. Moreover, the experimental and theoretical... 

Coordination Chemistry. The synthesis and reactivity of the complexes Fe2Ru(CO)i2-/ (CNBu ) and FeRu2(CO)i2- (GNBu% have also been reported." ... 

The majority of U(V1) coordination chemistry has been explored with the trans-ddo s.o uranyl cation, UO " 2- The simplest complexes are ammonia adducts, of importance because of the ease of their synthesis and their versatihty as starting materials for other complexes. In addition to ammonia, many of the ligand types mentioned ia the iatroduction have been complexed with U(V1) and usually have coordination numbers of either 6 or 8. As a result of these coordination environments a majority of the complexes have an octahedral or hexagonal bipyramidal coordination environment. Examples iuclude U02X2L (X = hahde, OR, NO3, RCO2, L = NH3, primary, secondary, and tertiary amines, py n = 2-4), U02(N03)2L (L = en, diamiaobenzene n = 1, 2). The use of thiocyanates has lead to the isolation of typically 6 or 8 coordinate neutral and anionic species, ie, [U02(NCS)J j)/H20 (x = 2-5). 

The diazaphosphane or aminoiminophosphane ligands with a NPN framework are another subclass of cyclophosphazenes. These compounds with both phosphorus in oxidation state (111) [104-110] and (V) [111-112] have been employed in the synthesis of four membered heterocycles and coordination chemistry with group 13 derivatives. Several complexes of trivalent phosphorus derivatives with both aluminum halide and alkyls are known as illustrated for 48 in Scheme 21 [113-119]. The structure determination of 48 confirms the formation of a four membered metallacycle [116, 117],... 

During the last year several new journals have appeared, in which papers of interest to organometallic chemists are published. Apart from thtjournal of Coordination Chemistry, which deals with general aspects of the chemistry of complex compounds, vehicles for preliminary communication in the area of synthesis and structure determination have commenced. A detailed breakdown of these, and of the volumes of the Elsevier journals in organometallic chemistry are given. 

Synthesis, coordination chemistry and analytical uses of monothio-/3-diketones Sulphinato complexes... 

Recently, Newkome et al. [165] described the synthesis of dendritic lock and key complexes, such as 78, which is based on the well-researched bzsterpyridine-ruthenium (—(Ru)—) coordination chemistry (Fig. 33). Dendritic terpyridines of the first and second generation were reacted with RuC13 and this formed the... 

The above account of selectivity of inorganic plus organic chemistry in synthesis is given rather extensively to stress three points. All the four (Mg, Fe, Co and Ni) porphyrin products came from one source, the synthesis of uroporphyrin. The basis of selection is very different from that in primitive centres which use thermodynamic stability constant selectivity based on different donor atoms for different metal ions. Here, all ion complexes have the same donor atoms, nitrogen, the most constrained being the coordination of Mg2+ by five nitrogens exactly as is seen for Fe in haemoglobin. Hence, there also has to be a new control feedback to ensure that the appropriate quantities of each metal cofactor is produced in a balanced way, that is synthesis from uroporphyrin has to be divided based upon... 

Reports on the coordination chemistry of A-heterocyclic carbene-containing metal complexes started to appear as long ago as 1968,50,51 while metal-free carbenes have only been isolated very recently.52 In view of the fact that the general chemistry and applications of organic carbenes and related metal complexes in chemical synthesis have been reviewed several times recently,53-57 examples limited only to those carbene complexes with silver(i) have been discussed. Nevertheless, it is worth mentioning that the developments in silver(i) A-heterocyclic carbenes have also been reviewed recently by Lin.5... 

Following the original paper, reports of the synthesis of new crowns and crown-like molecules proliferated. A typical property of these systems is their ability to form stable complexes with the alkali metal and alkaline earth ions. Prior to the synthesis of the crowns, the coordination chemistry of the above ions with organic ligands had received very little attention. A further impetus to the study of such complexes was the recognition of the important role of Na+, K+, Mg2+ and Ca2+ ions in biological systems. 

The development, synthesis, and the coordination chemistry of novel metal complexes with deep binding cavities have been described. It was demonstrated that the doubly deprotona-ted forms of the macrocycles (LR)2 support the formation of... 

The chemistry of titanium has been reviewed in COMC (1982) and COMC (1995)40 41 as well as in Comprehensive Coordination Chemistry II. 2 Since then, several contributions have covered the coordination chemistry of cyclopenta-dienyltitanium carboxylates and related complexes,43 new titanium imido chemistry,44 the use of titanium(iv) chloride45 and isopropoxide46 in stereoselective synthesis, the preparation and synthetic applications of l, -dicarba-nionic titanium intermediates47 and organotitanium complexes,48 49 and titanium-catalyzed enantioselective... 

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