Synthesis of Dideoxy-octonic Acid and Cyclic and Acyclic Derivatives Thereof
Christian Czaschke1, Ruben Figueira de Abreu1, Christian B W Stark1
1Department of Chemistry, Institute for Organic Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, D-20146 Hamburg, Germany.
Abstract:
Oxidative cleavage of N-acetyl-neuraminic acid (Neu5Ac, 1) leads to the open chain octonic acid (ADOA, 2), which under various conditions is transformed into an acyclic acid or ester or into a six- or five-membered octonic acid lactone and lactam, respectively. All reactions proceed with high selectivity and in good yields. Strikingly, a simple switch of reaction conditions from basic to acidic catalysis leads to a complete switch in regioselectivity during a crucial cyclization step.
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