Js. Parry et al., Synthesis and characterization of the first sandwich complex of trivalent thorium: A structural comparison with the uranium analogue, J AM CHEM S, 121(29), 1999, pp. 6867-6871
Reduction of the bulky 8-annulene thorium complex [Th{COT(TBS)(2)}(2)] (COT
(TBS)(2) = eta-C8H6(tBuMe(2)-Si)(2)-1,4) by potassium yields the anionic co
mpound {Th[COT(TBS)(2)](2)}K .(DME)(2), which was crystallographically char
acterized and is the first sandwich complex of Th(III). EPR spectroscopy in
dicates that the molecule possesses a 6d(1) ground state. A structural comp
arison is made with the isostructural uranium(III) complex and the thorium(
IV) parent compound.