Miscellaneous Applications of Carbohydrate Auxiliaries

In the remainder of this chapter, some other applications of carbohydrate auxiliaries are outlined. 

SCHEME 10.89 Allyl alcohols can be converted to chiral 1,2-diols using sugar-derived auxiliaries. 

SCHEME 10.91 Sugar-derived auxiliaries can influence the stereochemical course of the reduction of carbonyls. 

Higher substituted five- and six-membered lactones were also prepared by this procedure, but the enantiomeric excesses of the products were lower. The authors explain the diastereoselectivity of the reduction by a chelate complex in which the metal ion coordinates the hydroxyl group at C-5, one ring oxygen atom and the carbonyl group, which is then attacked by the complex hydride. 

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