Problems and exercisesCis-Trans Isomerism: Relative Stability
1. True or false?
Discuss whether the following statement is true or false: “cis-But-2-ene is less stable than its trans isomer by 1 kcal/mol and, for that reason, it quickly converts into the trans isomer”.
2. Heats of hydrogenation
The heats of hydrogenation of but-1-ene, cis-but-2-ene and trans-but-2-ene are −30.3, −28.6 and −27.6 kcal/mol. Order them by stability and explain the order.
3. Does it have cis-trans isomers?
Which of these compounds show cis-trans isomerism? a) pent-1-ene; b) pent-2-ene; c) 2-methylbut-2-ene; d) 1-chloropropene; e) cyclohexene.