Practical, Multigram Preparation of Synthetically Useful, Enantiomerically Pure Building-Blocks from Quinic Acid

Abstract

The naturally abundant, enantiomerically pure cyclitol quinic acid (1) has been converted into the synthetically useful enone 2 in nearly quantitative yield using the operationally straightforward and reproducible protocols reported herein. The latter compound, which was obtained in multigram quantities, engages in a diastereoselective 1,2-addition reaction with a hydrazone-based nucleophile. Furthermore, the readily derived α-iodoenone 3 participates in both cross-coupling and α,β-annulation reactions. The results reported here emphasize that the now practically accessible cyclohexenones 2 and 3 are useful, enantiomerically pure building blocks for organic synthesis.