Evans David A, Fandrick Keith R, Song Hyun-Ji
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
J Am Chem Soc. 2005 Jun 29;127(25):8942-3. doi: 10.1021/ja052433d.
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.
通过双（恶唑啉基）吡啶-三氟甲磺酸钪（III）配合物催化，实现了α,β-不饱和2-酰基咪唑与富电子芳香亲核试剂的对映选择性傅克烷基化反应。这些α,β-不饱和2-酰基咪唑是傅克反应中有效的亲电试剂。所得加合物2-酰基咪唑可通过甲基化及随后咪唑残基的取代反应，轻松转化为酰胺、酯、羧酸、酮和醛。
