M. Ohkita et al., SINGLE-STEP SYNTHESIS OF NORBORNAN-2-ONE DITHIOACETALS FROM CYCLOPENT-2-EN-1-ONE DITHIOACETALS AND DIENOPHILES, Journal of the Chemical Society, Chemical Communications, (22), 1993, pp. 1676-1677
2-(2-Mercaptoethylthio)cyclopenta-1,3-dienes are thermally generated i
n situ from cyclopent-2-en-1-one dithioacetals under neutral condition
s and intercepted with dienophiles ultimately to give norbornan-2-one
dithioacetals.