title: Investigation of the Passerini and Ugi reactions in β-lactam aldehydes. Synthetic applications.
abstract: Passerini (P-3CR) and Ugi (U-4CR) reactions were investigated in 4-oxoazetidine-2-carboxaldehydes, affording the corresponding Passerini and Ugi adducts with moderate diastereoselectivity in high yields. Fortunately, the obtained mixtures of isomers syn/anti were separated in most cases. The scope of both IMCRs has been studied using a variety of isocyanides, carboxylic acids and amines. Ugi adducts were used for the preparation of unusual 2-azetidinones fused to medium-sized rings via RCM. In addition, β-lactam-diketopiperazine hybrids have also been prepared from the corresponding Ugi adducts.
authors.affiliation: Grupo de Lactamas y Heterociclos Bioactivos, Departamento de Química Orgánica I, Unidad Asociada al CSIC, Facultad de Química, Universidad Complutense de Madrid, 28040-Madrid, Spain. alcaideb@quim.ucm.es.
authors.forename: Benito
authors.initials: B
authors.lastname: Alcaide
authors.forename: Pedro
authors.initials: P
authors.lastname: Almendros
authors.forename: Cristina
authors.initials: C
authors.lastname: Aragoncillo
authors.forename: Ricardo
authors.initials: R
authors.lastname: Callejo
authors.forename: M Pilar
authors.initials: MP
authors.lastname: Ruiz
authors.forename: M Rosario
authors.initials: MR
authors.lastname: Torres
mesh_terms: D000447:Aldehydes / Q000138:chemical synthesis* / Q000737:chemistry*; D001384:Azetidines / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic; D047090:beta-Lactams / Q000737:chemistry*
chemical_list: D000447:Aldehydes; D001384:Azetidines; D047090:beta-Lactams