PO 455

Triamido-Triazamacrocyclic Metal Complexes
Ana M. Martins, José R. Ascenso, Alberto R. Dias, M. Teresa Duarte, Humberto Ferreira, Rui
T. Henriques
Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, Av. Rovisco Pais,
1049-001 Lisboa, Portugal. E-mail: [email protected]
Hexaco-ordinated
[Ti{1,4,7-(N(Ph’)SiMe2)3-tacn}],
[Ti{1,4,7-(N(Ph’)SiMe2)3-tacn}]X,
[Ti{1,4,7-(N(Ph’)SiMe2)3-tacu}] and [Ti{1,4,7-(N(Ph’)SiMe2)3-tacu}]X (X = I, PF6, C60; Ph’
= C6H5, C6H4F; tacn = triazacyclononane; tacu = triazacycloundecane) complexes have been
prepared and characterised by NMR and X-ray diffraction. The reaction of [Ti{1,4,7(N(Ph’)SiMe2)3-tacn}] with MeI in toluene led to the rearrangement of the ligand donor set
with formation of a phenylimido and a new macrocycle derivative that in solution display a
reversible intramolecular exchange between imido/amine and bis-amido fragments. The
molecular structure of the new complex is shown below.
The reactions of the neutral triamine-tacn or its lithium or sodium derivatives with
[Zr(NMe2)4]2 and ZrCl4 led to the cleavage of a Ntacn-pendant arm bond and formation of
[ZrX{1,4-{N(Ph’)SiMe2}2-(tacn’)}] (X = NMe2, Cl) where tacn’ means a triazacyclononane
derivative with a negative nitrogen function in the ring. The metathesis of the Zr-X bond (X =
Cl) with LiCCPh gave to [Zr(CCPh){1,4-{N(Ph’)SiMe2}2-(tacn’)}].