Abstract:
:The catalytic generation of chiral ester enolate equivalents from α,β-unsaturated aldehydes with chiral N-hetereocyclic carbene catalysts makes possible highly enantioselective hetero-Diels-Alder reactions. The reactions proceed under simple, mild conditions with both aliphatic and aromatic substituted enals as substrates. Previous attempts to employ these starting materials as enolate precursors gave structurally different products via catalytically generated homoenolate equivalents. Critical to the success of the enolate generation was the strength of the catalytic base used to generate the active N-heterocyclic carbene catalyst. To complement these studies, we have investigated the enolate structure using computational methods and find that it prefers conformations perpendicular to the triazolium core.
journal_name
Proc Natl Acad Sci U S Aauthors
Kaeobamrung J,Kozlowski MC,Bode JWdoi
10.1073/pnas.1007469107subject
Has Abstractpub_date
2010-11-30 00:00:00pages
20661-5issue
48eissn
0027-8424issn
1091-6490pii
1007469107journal_volume
107pub_type
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