Synthesis and stereochemistry of hydrogenated 1,1,4,4,7a-pentamethylindenes

Abstract

Ease of methylation of hydrogenated 2H-inden-2-ones depends on the presence of a double bond in the cyclohexane ring, and occurs readily with compound 20 but not with 10. Differences of reactivity are also noted in Wittig reactions. Most reactions of the system are highly stereoselective, and the stereochemistry of hydrogenated indenes is discussed.