title: Practical and highly enantioselective synthesis of beta-alkynyl-beta-amino esters through Ag-catalyzed asymmetric mannich reactions of silylketene acetals and alkynyl imines.
abstract: [reaction: see text] A readily available iso-leucine-based phosphine ligand is used to promote Ag-catalyzed Mannich reactions between silylketene acetals and various alkynyl imines. Reactions can be effected in the presence of 5 mol % catalyst, without the need for rigorous exclusion of air, and with commercially available solvents (without purification) to afford the desired beta-alkynyl-beta-amino esters in 84-94% ee and 61-91% isolated yield.
authors.affiliation: Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA.
authors.forename: Nathan S
authors.initials: NS
authors.lastname: Josephsohn
authors.forename: Emma L
authors.initials: EL
authors.lastname: Carswell
authors.forename: Marc L
authors.initials: ML
authors.lastname: Snapper
authors.forename: Amir H
authors.initials: AH
authors.lastname: Hoveyda
mesh_terms: D000080:Acetals / Q000737:chemistry; D000480:Alkynes / Q000138:chemical synthesis* / Q000737:chemistry*; D000596:Amino Acids / Q000138:chemical synthesis*; D002384:Catalysis; D004952:Esters; D007097:Imines / Q000737:chemistry; D007202:Indicators and Reagents; D015394:Molecular Structure; D012821:Silanes / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000080:Acetals; D000480:Alkynes; D000596:Amino Acids; D004952:Esters; D007097:Imines; D007202:Indicators and Reagents; D012821:Silanes; D012834:Silver