Showing papers by "Kunisuke Izawa published in 1988"

Synthesis of N-Acyl-α-amino acids by Cobalt Catalyzed Amido-carbonylation

Abstract: A variety of Nacyl-α-amino acids are synthesized from aldehyde and amide via cobalt catalyzed amido-carbonylation (Wakamatsu) reaction. The reaction proceeds under exactly the same conditions as used for the hydroformylation (Oxo) reaction. So, olefins, alcohols, epoxides and halides which give aldehydes under the reaction conditions can be satisfactorily used instead of aldehydes. When acetals are used as starting materials, N-acyl-α-amino esters are obtained. The intramolecular amido-carbonylation provides a convenient route to cyclic α-amino acids or esters. Furthermore, N-acyl-α-amino esters are synthesized from N-acylamines through anodic oxidation followed by amido-carbonylation with high efficiency. By utilizing the methodology, a highly stereoselective synthesis of teneraic acid 14 was achieved. Possible mechanisms for these new processes are discussed in detail.