Q.4-4-9P
Question
cis-1,2-Dimethylcyclopropane has more strain than trans-1,2-dimethylcyclopropane. How can you account for this difference? Which of the two compounds is more stable?
Step-by-Step Solution
Verified Answer
Cis configuration has more strain than trans configuration, and trans-1,2-dimethylcyclopropane is more stable.
1Cis and Trans configuration
Cis configuration is when two groups are on the same face of the ring, and trans configuration is when the groups are on opposite faces. Both isomers are stable, and neither can be converted into the other without breaking and reforming chemical bonds.
2Steric strain
The steric strain increases the potential energy because of repulsion between nonbonded atoms that approach each other closely.
3Comparison of the cis and trans structure of cyclopropane:
- Here, the ring has six-carbon.
- Have two methyl groups.
- In cis configuration, the two methyl groups are in the same plane, giving rise to steric strain.
- In trans configuration, the two methyl groups are in different planes hence, lessens the steric strain.
- As it is known, the lesser the energy of the molecule, the more stable it will be, and hence, it can be concluded that trans-1,2-dimethylcyclopropane is more stable.
Other exercises in this chapter
Q. 4-4-7P-a
Name the following substances, including the cis- or trans- prefix (redbrown= Br): &
View solution Q. 4-4-6P
Prostaglandin F2α, a hormone that causes uterine contraction during childbirth,has the following structure. Are the two hydroxyl groups (-OH) on thecy
View solution Q.4-4-8P
Each H↔H eclipsing interaction in ethane costs about 4.0 kJ/mol. Howmany such interactions are present in cyclopropane? What fraction of theoverall 1
View solution Q.4-4-11P-a
Two conformations of cis-1,3-dimethylcyclobutane are shown. What is the difference between them, and which do you think is likely to be more stable?
View solution