intramolecular couplings 11 20 (Scheme 7) and 22 23 + 24 (Scheme 8) are accomplished with a total yield of 59% and 54%, respectively. All the intramolecular couplings investigated so far proceed stereoselectively to give the C2-symmetrical cyclohexanes 7a, 20 and 23 with a fixed chair conformation. These results are easily explained, if a conformationalequilibriumE ⇄ F is operative in which large