Homocyclic Ligands

Inorganic Rings and Polymers of the p-Block Elements From Fundamentals to Applications 

The occurrence of E-E and, in some cases, E-C bond activation in the reaction of the cyclic ligands (RE) with transition metal complexes becomes more prevalent for the heavier pnictogens (E = As, Sb, Bi). The reaction of 

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The anionic [P5 Bu4] homocycle is a potentially versatile ligand in main group or transition metal complexes.The reaction of [Na(THF)4][P5 Bu4] with Et2AlCl produces the complex Et2Al(P5 Bu4)(THF) (11.7). However,... 

The lability of the E-E and E-C bonds in cyclostibines and cyclobismuthines is readily evident in reactions of these homocycles with metal carbonyls. Under mild conditions, complexes in which the antimony ligand acts as a two-electron donor towards the metal centres may be isolated, e.g. cyclo-( BuSb)4[W(CO)5] (n=l,2) cf. metal complexes of cyclophosphines, see Section 7.1.1). In boiling solvents, however, rupture of the inorganic homocycle and/or the E-C bonds... 

Wallasch, M. Vollmer, G. Sitzmann, H. A homocyclic carbene ligand. Abstracts of Papers, 221 th ACS National Meeting, Anaheim, CA, USA, March 28-April 1, 2004, INOR-996. 

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