Synthesis and reactions of ynol ester complexes of molybdenum and tungsten: Cleavage of the RCCO-C(O)R′ bond and of the RCC-OC(O)R′ bond of ynol ester ligands

Article abstract of DOI:10.1021/om00041a027

Reaction of the ketenyl complexes NEt₄[M(η²-RCCO) (S₂CNR″₂)₂(CO)] (3, M = Mo, R = Ph, R″ = Et; 4, M = W, R = Ph, R″ = Et (a), R = C₆H₄CMe₃-4, R″ = Et (b), R = Ph, R″ = Me (c)) and K[W(η²-4-Me₃C-C₆H₄CCO)(N ₂C₆H₇)₂(CO)] (5) with acyl halides R′COCl (or R′COBr) affords the (ynol ester)metal complexes [M(S₂CNR″)₂(CO)(η²-RCCOCOR′)] (8: M = Mo, R = Ph, R′ = Ph, R″ = Et) (9: M = W, R = Ph, R′ = Me (a), Ph (b), CHCH₂ (c), trans-CHCHMe (d), trans-CHCHPh (e), R″ = Et; R = C₆H₄CMe₃-4, R′ = Me (f), CH₂Ph (g), CMe₃ (h), R″ = Et; R = Ph, R′ = CMe₃, R″ = Me (i)) and [W(N₂C₆H₇)₂-(CO)(η ²-4-Me₃C-C₆H₄CCOCOR′)] (10: R = C₆H₄CMe₃-4, R′ = CMe₃ (a), CH₂Ph (b), C₆H₄-OMe-4 (c)). Reaction of the ynol ester complexes [W(S₂CNEt₂)₂(CO)(η²-4-Me ₃C-C₆H₄CCOCOCH₂R)] (R = H (9f), Ph (9g)) with dimethylamine affords the ketenyl complex [H₂NMe₂] [W(η²-4-Me₃C-C₆H₄CCO)(S ₂CNEt₂)₂(CO)]. The ynol ester complexes [W(LL)₂(CO)(η²-4-Me₃C-C₆H ₄CCOCOCH₂Ph)] (LL = S₂CNEt₂ (9g), N₂C₆H₇ (10b)) react with NaN(SiMe₃]₂ to give the ketenyl complexes Na[W(η²-4-Me₃C-C₆H₄CCO)(LL) ₂(CO)]. Reaction of [W(S₂CNEt₂)₂(η²-4-Me ₃C-C₆H₄CCOCOCMe₃)(CO)] (9h) with HNMe₂ gives [W(S₂CNEt₂)₂-(η²-4-Me ₃C-C₆H₄CCNMe₂)(CO)] (11). Reaction of 9h with PMe₃ gives [W(S₂CNEt₂)₂(η²-4-Me ₃C-C₆H₄CCSCSNEt₂)(CO)][Me ₃CO₂] (12). The reaction of 4b with PMe₃ affords [W(η²-4-Me₃C-C₆H₄CCO)(S ₂CNEt₂)(CO)(PMe₃)₂] (13). The (ynol ether)metal complexes [M(S₂CNEt₂)₂(CO)(η²-RCCOMe)] (6, M = Mo, R = Ph; 7, M = W, R = C₆H₄CMe₃-4) were prepared by reaction of NEt₄[M(η²-RCCO)(S₂CNR″ ₂)₂(CO)] with CF₃SO₃CH₃.