Synthesis of Quaternary Carbon Stereogenic Centers by Diastereoselective Conjugate Addition of Boron-Stabilized Allylic Nucleophiles to Enones
Michael Z. Liang, Simon J. Meek
Abstract
A method for the site-selective and diastereoselective conjugate addition of boron-stabilized allylic nucleophiles to α,β-unsaturated ketones is disclosed. Transformations involve easily prepared γ,γ-disubstituted allyldiboron reagents and proceed in the presence of a fluoride activator at 80 °C. Reactions proceed with a wide variety of enones and allyldiboron reagents efficiently to deliver ketone products that contain otherwise difficult-to-access vicinal β-tertiary and γ-quaternary carbon stereogenic centers and an alkenylboron moiety. The utility of the method is highlighted by several transformations, including cross-coupling and carbocyclizations.
Topics & Concepts
StereocenterChemistryNucleophileConjugateReagentAllylic rearrangementMoietyKetoneVicinalCombinatorial chemistryStereochemistryOrganic chemistryMedicinal chemistryEnantioselective synthesisCatalysisMathematicsMathematical analysisOrganoboron and organosilicon chemistryAdvanced Synthetic Organic ChemistryAsymmetric Synthesis and Catalysis