Complexes containing coordinated halocarbons

In 1978 Beck, Schloter, Siinkel, and Urban reported the synthesis of compounds formulated on the basis of elemental analysis and IR spectroscopy as [M(CO)3(CH2Cl2)Cp][PF6] (where M = Mo, Bands 

In conclusion, the generation of solvento-complexes as reactive intermediates is extensively used in synthesis. Three distinct approaches have been developed to provide solvent-binding sites (i) conversion of ligands into products with low solubility or their transformation into volatile compounds, (ii) chemical transformations of coordinated ligands where the products of the reaction are poorer donors and are expelled from the coordination sphere of the complex, and (Hi) manipulation of the metal oxidation state to affect ligand-binding properties. 

For general reviews see (a) N. Farrell, Transition Metal Complexes as Drugs and Chemotherapeutic Agents in Catalysis by Metal Complexes, eds. B. R. James and R. Ugo, Vol. 11, (Reidel-Kluwer, Dordrecht, 1989) (b) N. Farrell, Cancer Investigation 11 (1993) 578. 

Matsumoto, and K. Fuwa, Inorg. Chim. Acta 65 (1982) L171. 

Kuduk Jaworska and B. Jezowska-Trzebiatowska, Polish /. Chem. 55 (1981) 1143. 

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Metal-solvent interactions can be conveniently considered in terms of the hard-soft acid-base (HSAB) principle (Chapter 1). For example, palladium(II) is a soft metal center and so the hard oxygen donor solvent, diethyl ether, interacts only poorly with it. Simple valence bond models have been presented that adequately explain such soft metal-hard base interactions. In this chapter complexes containing coordinated halocarbons are treated in a separate section (3.7) from those that contain other "hard bases" since such species have only been recognized as well-defined complexes in recent years and their potential for exploitation in coordination chemistry merits special attention. 

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