Peptide-catalyzed diastereo- and enantioselective cyclopropanation of aromatic α,β-unsaturated aldehydes.
نویسندگان
چکیده
Highly diastereo- and enantioselective cyclopropanation of aromatic α,β-unsaturated aldehydes was achieved using a resin-supported peptide catalyst under aqueous conditions. In the peptide sequence, the residue possessing an oxygen atom with the appropriate length of the side chain was essential for attaining good diastereoselectivity.
منابع مشابه
Enantioselective cyclopropanation of enals by oxidative N-heterocyclic carbene catalysis.
Carbene catalysed redox activation of α,β-unsaturated aldehydes is applied for generation of α,β-unsaturated acyl azoliums which undergo cyclopropanation upon reaction with a sulfur ylide and an alcohol to give the corresponding cyclopropanecarboxylic acid esters. With chiral carbenes good to excellent diastereo and enantioselectivities are obtained.
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ورودعنوان ژورنال:
- Organic letters
دوره 15 19 شماره
صفحات -
تاریخ انتشار 2013