244075-44-3Relevant academic research and scientific papers
Reactivity of Electron-Deficient Benzoheterocycle Triosmium Clusters. 5. The Chemistry of Os3(CO)9(μ3-η 2-(C(9)-N)-5,6-benzoquinolyl)(μ-H) and Its Phosphine Derivative
Smith, Ryan,Rosenberg, Edward,Hardcastle, Kenneth I.,Vazquez, Venessa,Roh, Jay
, p. 3519 - 3527 (1999)
The reactivity of Os3(CO)9(μ3-η2-C 13H8N)(μ-H) (1) is reported. The reaction of 1 with triphenyl phosphine gives Os3(CO)9(μ-η2-C13H 8N)(μ-H)(PPhOs) (2), in which the phosphine is bonded to the same osmium as the C(10) of the heterocyclic ring, isostructural with the quinoline analogue. Thermal or photochemical decarbonylation of 2 gives moderate yields of Os3(CO)8(μ3-η3-C 13H8N)(μ-H)PPh3 (3), which has a σ-π-vinyl bonding mode with the C(9)-C(10) double bond and not the expected μ3-η2 electron-deficient bonding mode. The reactivity of 1 with hydride followed by protonation yields the electron-precise Os3(CO)9(μ3-η2-C 13H9N)-(μ-H)2 (4), and labeling experiments using D-/H+ indicate direct nucleophilic attack at C(9) by the deuteride followed by protonation at the metal core. The reaction of 1 with lithium isobutyrile nitrile followed by protonation gives Os3(CO)9(C13H9(4-(CH 3)2CCN)N)(μ-H) (5), a result of nucleophilic addition across the 3,4 double bond. Reaction with n-butyllithium followed by protonation, on the other hand, gives three products, Os3(CO)9(μ3-η2-C 13-H8(9-C4H9)N)(μ-H)3 (6), the result of addition at the 9-position, Os3(CO)9(μ3-η2-C 13H7(6-C4H9)N)-(μ-H) (7), and Os3(CO)9(μ3-η2-C 13H7(5-C4H9)N)(μ-H) (8), both the result of nucleophilic substitution for hydrogen. The solid-state structures of 3 and 8 are reported, and the mechanistic implications of these results for the synthetic methodology being developed for these electron-deficient clusters will be discussed.
