Ruthenium-catalyzed ring-closing metathesis accelerated by long-range steric effect.
نویسندگان
چکیده
Ruthenium-based metathesis catalysts with a N-heterocyclic carbene ligand bearing 2,3,4,5-tetraphenylphenyl moieties (1-TPPh and 1-TPPh*) are developed. The highly active catalyst system has been realized in THF by the combination of 1-TPPh* and CuCl as a phosphine scavenger.
منابع مشابه
Enantioselective synthesis of 5-epi-citreoviral using ruthenium-catalyzed asymmetric ring-closing metathesis.
Chiral ruthenium olefin metathesis catalysts can perform asymmetric ring-closing reactions in > or = 90% ee with low catalyst loadings. To illustrate the practicality of these reactions and the products they form, an enantioselective total synthesis of 5-epi-citreoviral was completed by using an asymmetric ring-closing olefin metathesis reaction as a key step early in the synthesis. All of the ...
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عنوان ژورنال:
- Chemical communications
دوره 47 34 شماره
صفحات -
تاریخ انتشار 2011