New Synthesis of .alpha.-Amino Acid N-Carboxy Anhydrides through Baeyer-Villiger Oxidation of .alpha.-Keto .beta.-Lactams
摘要:
A conceptually new route for the generation of optically active alpha-aminoacid N-carboxy anhydrides (NCAs) and hence alpha-amino acid derivatives is described. The strategy developed is simple and consists of the oxidation of alpha-hydroxy beta-lactams to the corresponding alpha-keto beta-lactams followed by a Baeyer-Villiger rearrangement. By that means, a wide variety of functionalized alpha-aminoacid N-carboxy anhydrides can be obtained, i.e., alpha,beta-diamino acid and alpha-amino beta-hydroxy acid-derived NCAs. The starting alpha-hydroxy(alkoxy) beta-lactams required for the study are easily prepared in large quantities either by the cycloaddition reaction of achiral alkoxyketenes with chiral aldehyde-derived imines or by the addition of Grignard reagents to a 3-(benzyloxy)-4-formylazetidin-2-one. The construction of a wide variety of NCA's from non-amino acid precursors becomes the most remarkable point of the reaction methodology developed.
New Synthesis of .alpha.-Amino Acid N-Carboxy Anhydrides through Baeyer-Villiger Oxidation of .alpha.-Keto .beta.-Lactams
摘要:
A conceptually new route for the generation of optically active alpha-aminoacid N-carboxy anhydrides (NCAs) and hence alpha-amino acid derivatives is described. The strategy developed is simple and consists of the oxidation of alpha-hydroxy beta-lactams to the corresponding alpha-keto beta-lactams followed by a Baeyer-Villiger rearrangement. By that means, a wide variety of functionalized alpha-aminoacid N-carboxy anhydrides can be obtained, i.e., alpha,beta-diamino acid and alpha-amino beta-hydroxy acid-derived NCAs. The starting alpha-hydroxy(alkoxy) beta-lactams required for the study are easily prepared in large quantities either by the cycloaddition reaction of achiral alkoxyketenes with chiral aldehyde-derived imines or by the addition of Grignard reagents to a 3-(benzyloxy)-4-formylazetidin-2-one. The construction of a wide variety of NCA's from non-amino acid precursors becomes the most remarkable point of the reaction methodology developed.
New Synthesis of .alpha.-Amino Acid N-Carboxy Anhydrides through Baeyer-Villiger Oxidation of .alpha.-Keto .beta.-Lactams
作者:Claudio Palomo、Jesus M. Aizpurua、Inaki Ganboa、Francois Carreaux、Carmen Cuevas、Elena Maneiro、Jesus M. Ontoria
DOI:10.1021/jo00090a033
日期:1994.6
A conceptually new route for the generation of optically active alpha-aminoacid N-carboxy anhydrides (NCAs) and hence alpha-amino acid derivatives is described. The strategy developed is simple and consists of the oxidation of alpha-hydroxy beta-lactams to the corresponding alpha-keto beta-lactams followed by a Baeyer-Villiger rearrangement. By that means, a wide variety of functionalized alpha-aminoacid N-carboxy anhydrides can be obtained, i.e., alpha,beta-diamino acid and alpha-amino beta-hydroxy acid-derived NCAs. The starting alpha-hydroxy(alkoxy) beta-lactams required for the study are easily prepared in large quantities either by the cycloaddition reaction of achiral alkoxyketenes with chiral aldehyde-derived imines or by the addition of Grignard reagents to a 3-(benzyloxy)-4-formylazetidin-2-one. The construction of a wide variety of NCA's from non-amino acid precursors becomes the most remarkable point of the reaction methodology developed.