Synthesis and characterization of thiolate, -amido, and -oxy heterocyclic-containing niobocene complexes: X-ray molecular studies of [Nb(eta(5)-C5H4SiMe3)(2)(eta(2)-N,S-S(C6H7N2))] (3)

The thermal treatment of the bis((trimethylsilyl)(cyclopentadienyl)niobium trihydride complex, [Nb(eta(5)-C5H4SiMe3)(2)(H)(3)], with 1 equiv. of the c orresponding mercapto-, hydroxy-, amino-pyridine or pyrimidine, such as 2-m ercaptopyridine, 2-mercaptopyrimidine, 2-mercapto-4,6-dimethylpyrimidine; 2 -hydroxypyridine, 2-hydroxy-6-methylpyrimidine, 6-hydroxy-2,4-dimethylpyrim idine, 8-hydroxyquinoline; 2-aminopyridine, 2-amino-4,6-dimethylpyridine, 2 -amino-4,6-dimethylpyrimidine, affords new families of thiolate-, oxy-, ami do-pyridine and -pyrimidine containing niobocene derivatives, namely [Nb(et a(5)-C5H4SiMe3)(2)L] where L=(eta(2)-N,S-S(C5H4N)) (1), (eta(2)-N,S-S(C4H3N 2)) (2), (eta(2)-N,S-S(C6H7N2)) (3), (eta(2)-N,O-O(C5H4N)) (4), (eta(2)-N,O -O(C6H6N)) (5), (eta(2)-N,O-O(C6H7N2)) (6), (eta(2)-N,O-O(C9H6N)) (7), (eta (2)-N,N-HN(C5H4N)) (8), (eta(2)-N,N-HN(C7H8N)) (9), (eta(2)-N,N-HN(C6H7N2)) (10). All the complexes were characterized by spectroscopic methods, and t he molecular structure of complex [Nb(eta(2)-C5H4SiMe3)(2)(eta(2)-N,S-S(C6H 7N2))] (3) has been determined by an X-ray diffraction study. (C) 2000 Else vier Science S.A. All rights reserved.