Tungsten and Molybdenum Alkyl or Aryl Complexes That Contain the [(C6F5NCH2CH2)3N]3- Ligand

[N 3 N F ]W(OC 6 F 5 ) and [N 3 N F ]W(O-3,5-Me 2 C 6 H 3 ) ([N 3 N F ] 3 - = [(C 6 F 5 NCH 2 CH 2 ) 3 N] 3 - ) can be prepared readily from [N 3 N F ]WCl in good yields. An X-ray study of the latter revealed an approximately trigonal structure with the phenoxide in the trigonal pocket. Alkylation of [N 3 N F ]WCl with LiCH 2 R (R = Me, n -Pr, SiMe 3, CMe 3 ) reagents in toluene at room temperature led to the evolution of molecular hydrogen and formation of the corresponding tungsten(VI) alkylidyne complexes, [N 3 N F ]W⋮CR (R = Me, n -Pr, SiMe 3, CMe 3 ). The intermediate [N 3 N F ]W(CH 2 SiMe 3 ) decomposed in a first-order manner to give [N 3 N F ]W⋮CSiMe 3 (Δ H ⧧ = 20.3 ± 0.2 kcal/mol, Δ S ⧧ = −7 ± 1 eu). An X-ray study of [N 3 N F ]W⋮CSiMe 3 showed it to have the expected, relatively undistorted, structure in which the W−C triple bond distance is 1.768(6) Å. Although attempts to prepare [N 3 N F ]WCH 3 were not successful, [N 3 N F ]W⋮CH could be prepared by reacting [N 3 N F ]WCl with cyclopropyllithium in toluene. [N 3 N F ]MoCl reacts with LiCH 2 SiMe 3 or LiCH 2 CMe 3 in toluene to yield [N 3 N F ]Mo(CH 2 CMe 3 ) or [N 3 N F ]Mo(CH 2 SiMe 3 ), respectively. Thermolysis of [N 3 N F ]Mo(CH 2 CMe 3 ) produced [N 3 N F ]Mo⋮CCMe 3 in a first-order reaction at 121 °C ( k = 7.9(5) × 10 - 5 s - 1 ). Several labeling experiments are consistent with the proposal that β-elimination competes with α-elimination and loss of molecular hydrogen in the [N 3 N F ] 3 - system. [N 3 N F ]WI reacts with aryllithium reagents (Ar = Ph, 3,5-Me 2 C 6 H 3 ) to yield [N 3 N F ]WPh and [N 3 N F ]W(3,5-Me 2 C 6 H 3 ). The aryl complexes react with hydrogen (3 atm) in toluene at 40 °C to yield diamagnetic [N 3 N]WH 3 and are cleanly oxidized by pyridine N-oxide. An X-ray study of [N 3 N F ]W(O)(3,5-Me 2 C 6 H 3 ) revealed it to have a pseudo-octahedral structure. [N 3 N F ]W(3,5-Me 2 C 6 H 3 ) reacts with trimethylsilyl azide to give [N 3 N F ]W(NSiMe 3 )(3,5-Me 2 C 6 H 3 ).