Lanthanide(III) Amidinates with Six‐ and Seven‐Coordinate Metal Atoms

The crystalline lithium N, N′‐diorganoamidinates Li[PhC(NR)2] (1: R = c‐C6H11, 2: R = iPr) and Li[(CF3)3C6H2C(N‐c‐C6H11)2] (3) have been obtained by the reaction of phenyllithium or 2, 4, 6‐tris(trifluoromethyl)phenyllithium, resp., with diorganocarbodiimides R‐N=C=N‐R (R = c‐C6H11, iPr). These amidinates have been used for the synthesis of the homoleptic lanthanide(III) amidinates [PhC(N‐c‐C6H11)2]3Ln (4—6: Ln = Pr, Nd, Sm) and [PhC(NiPr)2]3Pr (7). Seven‐coordinate Lewis‐base adducts of the type [PhC(NSiMe3)2]3Ln(NCPh) (8, 9: Ln = Sm, Eu) have been prepared by addition of benzonitrile to the homoleptic precursors [PhC(NSiMe3)2]3Ln. The compounds 2 (as its THF adduct), 4, 6, 8 and 9 have been structurally characterized by single crystal X‐ray analyses.