The synthesis and characterisation of novel Li and Yb complexes is reported, in which the monoanionic β-diketiminato ligand has been (i) reduced (SET or 2 × SET), (ii) deprotonated, or (iii) C–N bond-cleaved. Reduction of the lithium β-diketiminate Li(LR,R′)
[LR,R′
= N(SiMe3)C(R)CHC(R′)N(SiMe3)] with Li metal gave the dilithium derivative [Li(tmen)(μ-LR,R′)Li(OEt2)]
(4, R = R′
= Ph; or 5, R = Ph, R′
= But). When excess of Li was used the dimeric trilithium β-diketiminate [Li3(LR,R′)(tmen)]2
(6, R = R′
= C6H4But-4 = Ar) was obtained. Similar reduction of [Yb(LR,R′)2Cl] gave [Yb{(μ-LR,R′)Li(thf)}2]
(1, R = R′
= Ph; or 2, R = R′
= C6H4Ph-4 = Dph). Use of the Yb–naphthalene complex instead of Li in the reaction with [Yb(LPh,Ph)2] led to the polynuclear Yb clusters [Yb3(LPh,Ph)3(thf)]
(3), [Yb3(LPh,Ph)2(dme)2]
(7), or [Yb5(LPh,Ph)(L1)(L2)(L3)(thf)4]
(8)
[L1
= N(SiMe3)C(Ph)CHC(Ph)N(SiMe2CH2), L2
= NC(Ph)CHC(Ph)H, L3
= N(SiMe2CH2)] depending on the reaction conditions and stoichiometry. The structures of the crystalline complexes 4, 6·2½(hexane), 6·5(C6D6), 7 and 8 have been determined by X-ray crystallography (1 and 3 have been published).