Enantioselective Friedel-Crafts alkylations of alpha,beta-unsaturated 2-acyl imidazoles catalyzed by bis(oxazolinyl)pyridine-scandium(III) triflate complexes.
نویسندگان
چکیده
An enantioselective Friedel-Crafts alkylation with alpha,beta-unsaturated 2-acyl imidazoles and electron-rich aromatic nucleophiles catalyzed by bis(oxazolinyl)pyridine-scandium(III) triflate complexes has been accomplished. These alpha,beta-unsaturated 2-acyl imidazoles are effective electrophiles for the Friedel-Crafts reaction. The resulting adduct 2-acyl imidazole is easily converted to amides, esters, carboxylic acids, ketones, and aldehydes by methylation and subsequent displacement of the imidazole residue.
منابع مشابه
Enantioselective Friedel-Crafts alkylations catalyzed by bis(oxazolinyl)pyridine-scandium(III) triflate complexes.
The enantioselective Friedel-Crafts addition of a variety of indoles catalyzed by bis(oxazolinyl)pyridine-scandium(III) triflate complexes (Sc(III)-pybox) was accomplished utilizing a series of beta-substituted alpha,beta-unsaturated phosphonates and alpha,beta-unsaturated 2-acyl imidazoles. The acyl phosphonate products were efficiently transformed into esters and amides, whereas the acyl imid...
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 127 25 شماره
صفحات -
تاریخ انتشار 2005