Reactions of Nitridorhenium(V) and -Osmium(VI) Complexes with Acylating Agents.
Interaction of Re(N)L(2) [L = N(PSPh(2))(2)] 1 with (CF(3)CO)(2)O or RCOCl afforded air-sensitive acylimido-Re(V) complexes trans-Re[NC(O)CF(3)](OCOCF(3))L(2) 2 or trans-Re[NC(O)R]ClL(2) (R = CCl(2)H 3, CClH(2) 4, CH(3) 5), respectively. Treatment of 1 with (CX(3)CO)(2)O followed by recrystallization from CH(2)Cl(2)/hexane in air led to the formation of the corresponding parent imido complexes trans-Re(NH)(OCOCX(3))L(2) (X = F 6, Cl 7). The structure of 7 has been characterized by X-ray crystallography. The Re-N, average Re-S, and Re-O distances are 1.664(3), 2.441, and 2.116(3) Å, respectively. Deprotonation of 6 or 7 with Et(3)N gave 1. Recrystallization of 3 from CH(2)Cl(2)/hexane in air resulted in oxo-imido exchange and the isolation of the oxo-Re(V) species trans-Re(O)ClL(2). Treatment of 1 with tosyl anhydride gave trans-Re(NH)(OTs)L(2) (OTs = tosyl) 8. Reaction of [n-Bu(4)N][OsNCl(4)] with KL afforded trans-Os(N)ClL(2) 9, which has been characterized by X-ray crystallography. The Os-N, Os-Cl, and average Os-S bond distances in 9 are 1.64(1), 2.577(4), and 2.429 Å, respectively. Treatment of 10 with (CF(3)CO)(2)O, Ag(CF(3)CO(2)), or CF(3)CO(2)H resulted in chloride substitution and the formation of trans-Os(N)(OCOCF(3))L(2) 10. The Os-N, Os-O, and average Os-S distances in 10 are 1.643(5), 2.271(4), and 2.419 Å, respectively. Treatment of 1 with [Ph(3)C]BF(4) resulted in the isolation of trans-Re(NCPh(3))(F)L(2) 11, presumably via the cationic tritylimido intermediate [Re(NCPh(3))L(2)](+). Reaction of 9 with [Ph(3)C]BF(4) led to chloride abstraction and the formation of five-coordinate [Os(N)L(2)]BF(4) 12. The Os-N and average Os-S distances in 12 are 1.646(5) and 2.364 Å, respectively.
Leung
Wa-Hung
WH
Departments of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, and The University of Hong Kong, Pokfulam Road, Hong Kong.
Chim
Joyce L. C.
JL
Williams
Ian D.
ID
Wong
Wing-Tak
WT