Stereoselective Reduction of Bicyclic Ketals. An Efficient Synthesis of (−)-(<i>R</i>,<i>R</i>)-(<i>cis</i>-6-Methyltetrahydropyran-2-yl)acetic Acid, an Enantiomer of Civet Cat Constituent
(−)-(R,R)-(cis-6-Methyltetrahydropyran-2-yl)aceticacid, an enantiomer of civet cat constituent, was prepared in high yield by using a stereoselective reduction of bicyclic ketals as a key step.