CARB 2 |
| We have discovered in the last few years that diisobutylaluminum hydride (DIBAL-H) is achieving a remarkable A-D type bis-de-O-benzylation of fully benzylated a- and b-cyclodextrins (1). In order to understand this reaction a mechanistic model has been developped (2), involving two molecules of aluminum reagent. Based on this plausible mechanism, we have now achieved a selective clockwise duplication of this double ablation, through either a so-called bascule-bridge strategy (3) or other tricks. This new concept in cyclodextrin chemistry provides an unprecedented entry to highly differentiated cyclodextrins. (1) A.J. Pearce, P. Sina˙, Angew. Chem., Int. Ed. Engl. 2000, 39, 3610-3612 (2) T. Lecourt, A.J. Pearce, A. Hérault , M. Sollogoub, P. Sina˙, Chem. Eur. J., 2004, 12, 2960-2971 (3) O. Bistri, M. Sollogoub, P. Sina˙, Chem. Commun., 2006, 1112-1114 |
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Claude S. Hudson Award in Carbohydrate Chemistry: Symposium in Honor of Pierre Sina˙
8:45 AM-12:10 PM, Sunday, March 25, 2007 McCormick Place North -- Room N226, Level 2, Oral
Division of Carbohydrate Chemistry |