2006

Enantioselective synthesesO 0031 Direct Asymmetric Intermolecular Aldol Reactions Catalyzed by Amino Acids

and Small Peptides. — A wide variety of natural and non-peptidic amino acids, their tetrazole derivatives, amines as well as di- and tripeptides is tested as catalyst in the asymmetric aldol reaction of simple ketones with aromatic aldehydes. Excellent enan-tioselectivities are achieved for aliphatic amino acids like L-alanine, L-valine, the corresponding tetrazole derivatives as well as their dipeptides. The presence of water is essential. The influence of catalyst structure and solvents on the stereoselectivity is studied in detail. — (CORDOVA*, A.; ZOU, W.; DZIEDZIC, P.; IBRAHEM, I.; REYES, E.; XU, Y.; Chem. Eur. J. 12 (2006) 20, 5383-5397; Dep. Org. Chem., Arrhenius Lab., Univ. Stockholm, S-106 91 Stockholm, Swed.; Eng.) — Mischke

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