2000 protection, deprotection

protection, deprotectionO 0345

05 - 084Cerium(IV)-Catalyzed Deprotection of Acetals and Ketals underMildly Basic Conditions. — Application of a novel highly efficientdeprotection method with catalytic amounts of cerium ammonium nitrateunder mildly basic conditions (borate–HCl buffer solution) to a series ofacetals and ketals shows that the cerium catalyst is highly sensitive to sterichindrance in the ketal protecting group and/or in its immediate vicinity,e.g. prolonged reaction time required for deprotection of decalone derivative(VII) and total inertness of pinacol-derived ketal (IX) under these reactionconditions. — (MARKO, ISTVAN E.; ATES, ALI; GAUTIER, ARNAUD;LEROY, BERNARD; PLANCHER, JEAN-MARC; QUESNEL, YANNICK;VANHERCK, JEAN-CHRISTOPHE; Angew. Chem., Int. Ed. 38 (1999) 21,3207-3209; Lab. Chim. Org., Univ. Cathol. Louvain, B-1348 Louvain-la-Neuve,Belg.; EN)

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