Metal calix arene phosphine

The coordination chemistry of tertiary phosphine-functionalized calix[4]arenes have been described.279 Treatment of a bis(diphenylphosphino) or bis(dimethylphosphino) derivative of calix[4]arene with [PtCl2(COD)] leads to the formation of the corresponding dichloroplatinum(II) complex. The related diplatinum(II) species has also been reported with the tetrafunctionalized calix[4]arene.280 The mononuclear derivative is susceptible to oligomerization if the two free phosphine ligands are not oxidized or complexed to another metal center such as gold(I).279 The platinum(II) coordination chemistry of a mono-281 and diphosphite282 derived calix[ ]arene (n = 4 and 6, respectively) has also been described. 

Other signiflcant complexes of this type, containing one or more lanthanides, are formed by calixarenes (see Calixarenes) Much of this work has been prompted by their potential in separating lanthanides from uranium and other metals. A calixarene ligand with two amide substituents has been synthesised as an extractant for lanthanides dimeric Sm and Eu and monomeric Eu complexes have been prepared. Another calixarene, with four phosphine oxides attached, has been fixed to silica particles and the resulting system has been found to give very efficient extraction of Eu + and Ce + from simulated waste. A calix[4]arene complex of Gd + binds... 

Cs6k Z, Szalontai G, Czira G, Kollar L. Carbonylation (hydroformylation and hydrocarbalk-oxylation) reactions in the presence of transition metal p-tert-butyl-calix[4]arene-based phosphine and phosphinite systems. J Organomet Chem 1998 570(l) 23-9. 

Simply mixing solutions of the tetracationic diphosphine (175) with a tetraanionic calix[4]arene leads to the formation of supramolecular heterocapsules that can bind a transition metal ion within the cavity of the assembly, providing a new class of potential supramolecular catalysts. Sulfonated aryl-phosphines and -diphosphines form supramolecular adducts with cyclodextrins that are also of interest as new ligand systems,and the mechanism of such inclusion processes has attracted a theoretical study. ... 

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