Preparation, structure, derivatisation and NMR data of cyclohexane-1,2-diacetal protected carbohydrates

Acid catalysed reaction of monosaccharides with 1,1,2,2-tetramethoxycyclohexane results in selective protection of vicinal, diequatorial, diol functionality as a cyclohexane-1,2-diacetal (CDA). This new methodology complements classical cyclic acetal protecting group strategies which in general are not able to mask diols with such diequatorial stereochemistry. The resulting CDA protected derivatives can be readily functionalised to give rapid access to numerous key building blocks for oligosaccharide and natural product synthesis.