Synthese und Strukturen von (Monoorganyl)amiden und ‐imiden des Zirkoniums und Hafniums

Synthesis and Structures of (Monoorganyl)amides and ‐imides of Zirconium and Hafnium The tetrahalides MCl 4 (M = Zr 1 a , Hf 1 b ) react with LiNH t Bu with elimination of LiCl to yield [( t BuNH) 2 MN t Bu] 2 ( 3 ) (M = Zr 3a , Hf 3b ). Compounds 3 are thermally instable and oli‐gomerise above 100 °C with elimination of H 2 N t Bu. The reactions of (η 5 ‐C 5 Me 5 )MCl 3 (M = Zr 1 c , Hf 1 d ) with LiNHR (R = t Bu 2 a ,2,4,6‐Me 3 C 6 H 2 2 b , 2, 6‐ i Pr 2 C 6 H 3 2 c ) lead to (η 5 ‐C 5 Me 5 )M(NHR) 3 ( 4 ) (R = t Bu, M = Zr 4 a , Hf 4 b ; R = 2, 4,6‐Me 3 C 6 H 2 , M = Zr 4 c , Hf 4 d ; R = 2,6‐ i Pr 2 C 6 H 3 , M = Zr 4 e , Hf 4 f ). Compounds 4 are thermally very stable and melt without decomposition. When 1 c and 1 d react with LiNHPh ( 2 d ), dimers of composition [(η 5 ‐C 5 Me 5 )M(NHPh)NPh] 2 (M = Zr 5 a , Hf 5 b ) are obtained. The complexes (η 5 ‐C 5 Me 5 ) 2 MCl 2 (M = Zr 1 e , Hf 1 f ) react with 2 b to form (η 5 ‐C 5 Me 5 ) 2 M(NHR) 2 ( 6 ) (M = Zr 6 a , Hf 6 b ). Pyridine reacts with 4 e at 85 °C and replaces one molecule of 2,6‐ i Pr 2 C 6 H 3 NH 2 to give (η 5 ‐C 5 Me 5 )Zr‐(NHR)NR · Py ( 7 ). The single crystal X‐ray structures of 4 a, 4 f, 5 b and 7 are described.