Non-aqueous coordination chemistry

Many complexes of the group 1 metals prepared in non-aqueous conditions (e.g. in polar organic solvents) are known. Alkali metal ions are typically hard Lewis acids and favour coordination by hard O- and A-donor ligands. The use of macrocyclic ligands was detailed in Section 11.8, and in this section, we focus on examples of discrete molecular and polymeric species incorporating other types of O- and A-donors. The bonding in these types of compotuids is considered to be predominantly ionic. The use of stericaUy 

In Section 23.2, organometaUic compounds of the group 1 metals are described and these include examples in which the chelating ligand Me2NCH2CH2NMc2 (TMEDA) plays a stabihzing role. 

The following terms were introduced in this chapter. Do you know what they mean  

Greenwood and A. Eamshaw (1997) Chemistry of the Elements, 2nd edn, Butterworth-Heinemann, Oxford Chapter 4 gives a good account of the inorganic chemistry of the group 1 metals. 

Jansen and H. Nuss (2007) Z. Anorg. Allg. Chem., vol. 633, p. 1307 - Tonic ozonides . 

10 The structure of [ LiNH Bu g] determined by X-ray diffraction hydrogen and methyl-carbon atoms have been omitted for clarity [N.D.R. Barnett et al. (1996) 

Jansen and W. Schnick (1989) Progress in Solid State Chemistry, vol. 19, p. 47 - A review of alkali metal oxides, peroxides, superoxides and ozonides. 

Mair and R. Snaith (1994) Alkali metals Inorganic chemistry in Encyclopedia of Inorganic Chemistry, ed. R.B. King, Wiley, Chichester, vol. 1, p. 35 - A recent survey with a large number of references into the primary literature. 

Commun., p. 2321]. Colour code Li, red N, blue C, grey. 

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Encapsulation of a metal ion by a saturated organic framework is expected to lead to robust metal derivatives which are stable over a wide pH range and thus, for example, inhibit the hydrolysis which is characteristic of certain metal ions in aqueous solution. In this manner, the non-hydrolytic coordination chemistry of these ions in solution becomes accessible. Similarly, the redox chemistry of such encapsulated ions is of special interest, since there exists the prospect that the saturated organic shell might insulate the metal ion to a greater or lesser degree from the surrounding medium and hence markedly influence electron transfer reactions. 

N.V. Gerbeleu, S.P. Palii, A.A. Dobrov, L.A. Nemchinova, VI All-Union Conference on Non-Aqueous Solution Chemistry of Inorganic and Coordination Compounds, Abstracts, Rostov on Don, 1987, p. 26 (Russ.). 

V. Gutmann and E. Wychera, Inorg. Nucl. Chem. Lett., 2 (1966) 257 V. Gutmann, Coordination Chemistry in Non-Aqueous Solutions, Springer, Vienna, 1968 V. Gutmann, The Donor-Acceptor Approach to Molecular Interactions, Plenum Press, London, 1978. 

V. Gutmann, Coordination Chemistry in Non-Aqueous Solvents, Springer, Wien, 1968. 

The synthetic procedures are relatively simple and productive, the phosphonate group is chemically stable and non-coordinating, so in the future these compounds can be expected to play a more significant role in aqueous organometallic chemistry. 

The oxidizing properties of thallium(III) in both aqueous and non-aqueous media obviously preclude the existence of a number of compounds analogous to those found for aluminum, gallium and indium in this oxidation state. Thus, while there is much richer chemistry for thallium in the +1 state, there is a concomitant decrease in the detailed information on thallium(III) coordination chemistry. 

As in other fields of inorganic chemistry, some research on coordination compounds has been carried out in non-aqueous media. There are several reasons for this first, some compounds are not soluble in water, but will dissolve in other solvents (of course, solubilities can often be modified by judicious selection of the counter ion). In those cases in which the coordination compound reacts with water, the use of a non-aqueous solvent may be advantageous. A familiar example is the determination of the number of ions in a compound by measuring the conductivity in nitromethane or other highly polar solvent. In studying the self-exchange rate of the [Co(NH3)6]2+/3+system,... 

Gutmann, V. (1968) Coordination Chemistry in Non-aqueous Solutions, Springer, Vienna. 

Gutmann, V. Coordination chemistry in non-aqueous solutions. Wien Springer 1968. King, E. J. Acid-base equilibria, Oxford Pergamon Press 1965. 

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