A general method for the synthesis of cyclodextrinyl aldehydes and carboxylic acids

Article abstract of DOI:10.1021/jo00114a030

The selective synthesis of the primary-side monoaldehyde of β-cyclodextrin, 6-deoxy-6-formyl-β-cyclodextrin, was accomplished by oxidation of the corresponding tosylate utilizing the Nace reaction (DMSO/collidine). This monoaldehyde was then used as the starting material in several reactions including reduction, addition of NaHSO₃, addition of the α-nucleophiles hydroxylamine and hydrazine, and reductive amination. Of particular interest is the conversion of the monoaldehyde to the primary side carboxylic acid, 6-deoxy-6-carboxy-β-cyclodextrin, via bromine oxidation. This general method sequence can be applied to any tosyl derivative of cyclodextrin as demonstrated in the synthesis of β-cyclodextrin-A,D-dialdehyde and β-cyclodextrin-A,D-diacid.