(1R,2R)-2-(4-Methylenecyclohex-2-enyl)propyl (1R,4S)-camphanate

Esterification of a single diastereomer of 2-(4-methylene-cyclohex-2-enyl)p ropanol, (II), with (1R,4S)-(+)-camphanic acid [(1R,4S)-4,7,7-trimethyl-3-o xo-2-oxabicyclo [2.2.1]heptane-1-carboxylic acid] leads to the crystalline title compound, C20H28O4 The relative configuration of the camphanate was d etermined by X-ray diffraction analysis. The outcome clarifies the relative and absolute stereochemistry of the naturally occurring bisabolane sesquit erpenes beta-turmerone and beta-sesquiphellandrene, since we have converted (II) into both natural products via a stereospecific route.