Metal-promoted allylation, propargylation, or allenylation of azetidine-2,3-diones in aqueous and anhydrous media. Application to the asymmetric synthesis of densely functionalized 3-substituted 3-hydroxy-beta-lactams.
Metal-mediated carbonyl allylation, allenylation, and propargylation of optically pure azetidine-2,3-diones were investigated in both anhydrous and aqueous environments. Different metals promoters showed varied regioselectivities on product formation during allenylation/propargylation reactions of the keto-beta-lactams. The stereochemistry of the new C3-substituted C3-hydroxy quaternary center was controlled by placing a chiral auxiliary at C4. In this way, the coupling of azetidine-2,3-diones with a variety of propenyl-, propynyl-, and allenylmetal reagents offers a convenient asymmetric entry to potentially bioactive 3-substituted 3-hydroxy-beta-lactams.
Alcaide
B
B
Departamento de Química Orgánica I, Facultad de Química, Universidad Complutense, 28040-Madrid, Spain. alcaideb@eucmax.sim.ucm.es
Almendros
P
P
Aragoncillo
C
C
Rodríguez-Acebes
R
R
D000498:Allyl Compounds / Q000138:chemical synthesis; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis*; D001384:Azetidines / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry; D013237:Stereoisomerism; D047090:beta-Lactams
C116379:2-azetidinone; D000498:Allyl Compounds; D000900:Anti-Bacterial Agents; D001384:Azetidines; D007202:Indicators and Reagents; D009942:Organometallic Compounds; D047090:beta-Lactams