Both racemic ethyl 5-iodo-2-methylcyclohexanecarboxylate (1), known as Mediterranean fruit fly attractant ceralure B1, and its (−)-(1R, 2R, 5R) enantiomer 1a were conveniently synthesized from commercially available racemic trans-6-methyl-3-cyclohexenecarboxylic acid 2 or its (1R, 6R) enantiomer 2a. Key steps included an asymmetric Diels–Alder reaction using a sultam auxiliary and cyclization of the unwanted trans-5-iodo-trans-2- ...