title: Asymmetric Petasis Borono-Mannich Allylation Reactions Catalyzed by Chiral Biphenols.
abstract: Chiral biphenols catalyze the asymmetric Petasis borono-Mannich allylation of aldehydes and amines through the use of a bench-stable allyldioxaborolane. The reaction proceeds via a two-step, one-pot process and requires 2-8 mole % of 3,3'-Ph2-BINOL as the optimal catalyst. Under microwave heating the reaction affords chiral homoallylic amines in excellent yields (up to 99 %) and high enantioselectivies (er up to 99:1). The catalytic reaction is a true multicomponent condensation reaction whereas both the aldehyde and the amine can possess a wide range of structural and electronic properties. Use of crotyldioxaborolane in the reaction results in stereodivergent products with anti- and syn-diastereomers both in good diastereoselectivities and enantioselectivities from the corresponding E- and Z-borolane stereoisomers.
authors.affiliation: Department of Chemistry, Center for Molecular Discovery, Boston University, 24 Cummington Mall, Boston, MA, 02215, USA.
authors.forename: Yao
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Chemistry, Center for Molecular Discovery, Boston University, 24 Cummington Mall, Boston, MA, 02215, USA.
authors.forename: Scott E
authors.initials: SE
authors.lastname: Schaus
mesh_terms: D000447:Aldehydes / Q000138:chemical synthesis / Q000737:chemistry*; D000498:Allyl Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D000588:Amines / Q000138:chemical synthesis / Q000737:chemistry*; D001897:Boronic Acids / Q000138:chemical synthesis / Q000737:chemistry*; D002384:Catalysis; D008352:Mannich Bases / Q000138:chemical synthesis / Q000737:chemistry; D009284:Naphthols / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D000498:Allyl Compounds; D000588:Amines; C406944:BINOL, naphthol; D001897:Boronic Acids; D008352:Mannich Bases; D009284:Naphthols; D010636:Phenols
keywords: boronate; enantioselective synthesis; imine allylation; multicomponent reactions; organocatalysis