Highly regioselective Pd-catalyzed intermolecular aminoacetoxylation of alkenes and evidence for cis-aminopalladation and S(N)2 C-O bond formation.
نویسندگان
چکیده
Synthetic methods that achieve oxidative 1,2-difunctionalization of alkenes are very powerful in organic chemistry. Here we report the first examples of intermolecular Pd-catalyzed aminoacetoxylation of alkenes with phthalimide as the nitrogen source and PhI(OAc)2 as the stoichiometric oxidant and source of acetate. These reactions are highly regio- and diastereoselective, and mechanistic studies reveal that the reaction proceeds via cis-aminopalladation of the alkene followed by oxidative cleavage of the intermediate Pd-C bond with inversion of stereochemistry.
منابع مشابه
Palladium-catalyzed intermolecular aminoacetoxylation of alkenes and the influence of PhI(OAc)2 on aminopalladation stereoselectivity.
A modified protocol has been identified for Pd-catalyzed intermolecular aminoacetoxylation of terminal and internal alkenes that enables the alkene to be used as the limiting reagent. The results prompt a reassessment of the stereochemical course of these reactions. X-ray crystallographic characterization of two of the products, together with isotopic labeling studies, show that the amidopallad...
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عنوان ژورنال:
- Journal of the American Chemical Society
دوره 128 22 شماره
صفحات -
تاریخ انتشار 2006