High Oxidation State Molybdenum N-Heterocyclic Carbene Alkylidyne Complexes: Synthesis, Mechanistic Studies, and Reactivity
, , , , , , и .
Chemistry – A European Journal 23 (61): 15484-15490 (2017)

Abstract The first synthetic protocol to high oxidation state molybdenum(VI) N-heterocyclic carbene (NHC) alkylidyne complexes (NHC=1,3-diisopropylimidazol-2-ylidene, 1,3-dimethyl-4,5-R2-imidazol-2-ylidene, R2=H, Cl, CN) is reported. Steric limitations of the NHCs and the benzylidyne are described. All novel complexes were characterized by single crystal X-ray diffraction and solution NMR techniques. It was shown that all complexes presented here show activity in the self-metathesis of 1-phenyl-1-propyne at room temperature. To identify mechanistic differences, an experimental sequence to detect dissociation of ligands was developed. Results reveal dissociation of less electron-donating NHCs in course of the reaction. Mechanistic and reactivity differences were attributed to electronic and steric effects through Tolman's electronic parameter and the percentage of buried volume. Furthermore, Mo-1 containing the 1,3-dimethylimidazol-2-ylidene ligand showed good activity in self-metathesis reactions of p-substituted 1-phenyl-1-propynes with electron-donating moieties at room temperature.
  • @unibiblio
  • @dr.ruethlein
К этой публикации ещё не было создано рецензий.

распределение оценок
средняя оценка пользователей0,0 из 5.0 на основе 0 рецензий
    Пожалуйста, войдите в систему, чтобы принять участие в дискуссии (добавить собственные рецензию, или комментарий)