Resurrecting the Cornforth Model for Carbonyl Addition: Studies on the Origin of 1,2-Asymmetric Induction in Enolate Additions to Heteroatom-Substituted Aldehydes†
David A. Evans Prof.
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617-495-1460
Search for more papers by this authorSarah J. Siska
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617-495-1460
Search for more papers by this authorVictor J. Cee
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617-495-1460
Search for more papers by this authorDavid A. Evans Prof.
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617-495-1460
Search for more papers by this authorSarah J. Siska
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617-495-1460
Search for more papers by this authorVictor J. Cee
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA, Fax: (+1) 617-495-1460
Search for more papers by this authorFinancial support was provided by the National Institutes of Health (GM33327-16) and by Merck Research Laboratories.
Graphical Abstract
Weitere experimentelle Bestätigung für das Cornforth-Modell wurde im Rahmen einer Untersuchung der Aldolreaktion von Methyl-substituierten E- und Z-Enolaten mit α-Sauerstoff-substituierten Aldehyden erhalten. Die beobachtete Abhängigkeit der Diastereoseitenselektivität von der Konfiguration des Enolats ist eher mit dem Cornforth-Modell in Einklang als mit dem polaren Felkin-Anh-Modell (siehe Schema; X=OR, NR2, Cl).
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- 16Abbreviations: PFA=polar Felkin–Anh; DIPEA=diisopropylethylamine; 9-BBNOTf=9-borabicyclo[3.3.1]nonyl trifluoromethanesulfonate; TEA=triethylamine; LiHMDS=lithium hexamethyldisilazide; TMS=trimethylsilyl; THF=tetrahydrofuran; Bn=benzyl; TBS=tert-butyldimethylsilyl; pyr=pyridine; LDA=lithium diisopropylamide; TBDPS=tert-butyldiphenylsilyl.
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