title: Asymmetric synthesis of beta2-amino acids: 2-substituted-3-aminopropanoic acids from N-acryloyl SuperQuat derivatives.
abstract: Conjugate addition of lithium dibenzylamide to (S)-N(3)-acryloyl-4-isopropyl-5,5-dimethyloxazolidin-2-one (derived from l-valine) and alkylation of the resultant lithium beta-amino enolate provides, after deprotection, a range of (S)-2-alkyl-3-aminopropanoic acids in good yield and high ee. Alternatively, via a complementary pathway, conjugate addition of a range of secondary lithium amides to (S)-N(3)-(2'-alkylacryloyl)-4-isopropyl-5,5-dimethyloxazolidin-2-ones, diastereoselective protonation with 2-pyridone, and subsequent deprotection furnishes a range of (R)-2-alkyl- and (R)-2-aryl-3-aminopropanoic acids in good yield and high ee. Additionally, the boron-mediated aldol reaction of beta-amino N-acyl oxazolidinones is a highly diastereoselective method for the synthesis of a range of beta-amino-beta'-hydroxy N-acyl oxazolidinones.
authors: Department of Organic Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, UK OX1 3TA.
authors: James E
authors: JE
authors: Beddow
authors: Stephen G
authors: SG
authors: Davies
authors: Kenneth B
authors: KB
authors: Ling
authors: Paul M
authors: PM
authors: Roberts
authors: Angela J
authors: AJ
authors: Russell
authors: Andrew D
authors: AD
authors: Smith
authors: James E
authors: JE
authors: Thomson
mesh_terms: D000478:Alkylation; D000577:Amides / Q000737:chemistry; D000596:Amino Acids / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D021621:Imaging, Three-Dimensional; D008094:Lithium / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D010080:Oxazoles / Q000737:chemistry; D011522:Protons; D013237:Stereoisomerism; D015091:beta-Alanine / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000577:Amides; D000596:Amino Acids; D010080:Oxazoles; D011522:Protons; D015091:beta-Alanine; C064210:oxazolidine; C011757:2,3-diaminopropionic acid; D008094:Lithium