Phosphites as ligands in ruthenium-benzylidene catalysts for olefin metathesis.
نویسندگان
چکیده
The use of phosphites in second generation, ruthenium-based olefin metathesis pre-catalysts leads to an improvement in catalyst stability and activity at low catalyst loadings.
منابع مشابه
Ruthenium indenylidene “1st generation” olefin metathesis catalysts containing triisopropyl phosphite
The reaction of triisopropyl phosphite with phosphine-based indenylidene pre-catalysts affords "1(st) generation" cis-complexes. These have been used in olefin metathesis reactions. The cis-Ru species exhibit noticeable differences with the trans-Ru parent complexes in terms of structure, thermal stability and reactivity. Experimental data underline the importance of synergistic effects between...
متن کاملPyridine as trigger for chloride isomerisation in chelated ruthenium benzylidene complexes: implications for olefin metathesis.
The cationic pyridine adduct of a ruthenium complex bearing a chelating benzylidene and an N-heterocyclic carbene was identified as an intermediate during the activation of cis dichloro species and a novel triggering concept for olefin metathesis catalysts based on cationic species was disclosed.
متن کاملRuthenium Olefin Metathesis Catalysts Bearing Carbohydrate-Based N-Heterocyclic Carbenes.
Ru-based olefin metathesis catalysts containing carbohydrate-derived NHCs from glucose and galactose were synthesized and characterized by NMR spectroscopy. 2D-NMR spectroscopy revealed the presence of Ru-C (benzylidene) rotamers at RT and the rate of rotation was measured using magnetization transfer and VT-NMR spectroscopy. The catalysts were found to be effective at ring-opening metathesis p...
متن کاملDeactivation of ruthenium olefin metathesis catalysts through intramolecular carbene-arene bond formation.
for olefin metathesis have been reported, for which strikingly different influences of the ligands on the efficiency of C C bond formation have been observed. For example, notable effects have been found in the class of alkoxy benzylidene ligands first introduced by Hoveyda and coworkers. Phosphine-free complexes such as the secondgeneration Hoveyda–Grubbs catalyst (4 ; IMesH2= 1,3-dimesityl-4,...
متن کاملRuthenium nitronate complexes as tunable catalysts for olefin metathesis and other transformations.
Novel ruthenium(II) complexes were obtained as a result of a stoichiometric reaction of Grubbs' benzylidene second generation catalysts with 3-nitropropene. These stable complexes, formally ruthenaisoxazole N-oxide derivatives, display activity in both metathesis and non-metathetic processes such as cycloisomerisation, isomerisation and transfer hydrogenation.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Chemical communications
دوره 47 25 شماره
صفحات -
تاریخ انتشار 2011