Abstract: MATH/CHEM/COMP 2002, Dubrovnik,
June 24-29, 2002
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SYMMETRY AND
CHIRALITY IN METAL
FULLERENE
COMPLEXES
Viatcheslav I. Sokolov Institute of Organoelement Compounds, Russian Academy of Sciences, 28 Vavilov Street, Moscow, Russian Federation Polyunsaturated carbon clusters
discovered in 1985 [1] known as fullerenes are unique in their structure in several ways.
They form a family of similar molecules which can be considered as a
collective allotropic form of carbon. Fullerenes had been early recognized as
potential ligands of various hapticity for metals [2]. Formally it may vary from h1 to h6. The complete symmetry analysis of
mono- and di- h5 and h6 metal complexes of C60 and C70
(with identical metal fragments MLn) had been carried out and some
chiral pair combinations found, namely, one combination for C60(h6-MLn)2 and several
cases of h5/h5, h5/h6, and h6/h6 ML2 for C70 [3, 4]. It
was also shown that Pople’s Framework Group Approach [5] is useful for description of the
fullerene derivatives [6]. Fullerenes h2-coordinated to transition metals are
equivalent in terms of symmetry to other 1,2-derivatives, for example, to
osmate esters among which the chiral pairs had been identified earlier [7]. Chiral and
optically active derivatives of fullerenes has been recently reviewed [8]. Symmetries of some metal complexed fullerenes
with partially violated electronic structures will be also considered. 1 H.W.Kroto, J.R.Heath, S.C.O’Brien, R.F.Curl, R.E.Smalley, Nature 318 (1985)162. 2 (a) V.I.Sokolov, 181st Meeting of
Electrochemical Society, Abstracts, 662FUL, StLouis, USA, 1992; (b) V.I.Sokolov, Dokl. Akad. Nauk, 326, N 4 (1992) 647
(Engl. Transl. p. 209). 3 V.I.Sokolov, Molec. Mater. 7 (1996) 23. 4 V.I.Sokolov, Russ. Chem. Bull.
48, N 7 (1999) 1211 (Engl. Transl.
p. 1197). 5 J.A.Pople, J. Am. Chem. Soc. 102 (1980) 4615. 6 V.I.Sokolov, Fullerene Sci. &
Techn. 5, N 1 (1997) 281. 7 J.M.Hawkins, A.Meyer, M.Nambu. J.
Am. Chem. Soc. 115 (1993)
9844. 8 V.I.Sokolov, Russ. J. Org. Chem. 35, N 9 (1999) 1289 (Engl. Transl. p. 1257). |