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

The crystalline lithium N, N′ ‐diorganoamidinates Li[PhC(NR) 2 ] ( 1 : R = c ‐C 6 H 11 , 2 : R = i Pr) and Li[(CF 3 ) 3 C 6 H 2 C(N‐ c ‐C 6 H 11 ) 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 ‐C 6 H 11 , i Pr). These amidinates have been used for the synthesis of the homoleptic lanthanide(III) amidinates [PhC(N‐ c ‐C 6 H 11 ) 2 ] 3 Ln ( 4—6 : Ln = Pr, Nd, Sm) and [PhC(N i Pr) 2 ] 3 Pr ( 7 ). Seven‐coordinate Lewis‐base adducts of the type [PhC(NSiMe 3 ) 2 ] 3 Ln(NCPh) ( 8, 9 : Ln = Sm, Eu) have been prepared by addition of benzonitrile to the homoleptic precursors [PhC(NSiMe 3 ) 2 ] 3 Ln. The compounds 2 (as its THF adduct), 4 , 6 , 8 and 9 have been structurally characterized by single crystal X‐ray analyses.