CHEM 281 Chapter Notes - Chapter 3: Cyclohexane, Substituent, Methyl Group

• School: Simon Fraser University
• Department: Chemistry
• Course: CHEM 281
• Professor: Nabyl Merbouh

Document Summary

Chapter 3 notes part 19: an introduction to organic compounds. Both chair conformers of the trans isomer have one substituent in an equatorial position and the other in an axial position. Because the tert-butyl group is larger than the methyl group, the 1,3-diaxial interactions will be stronger when the tert-butyl group is in an axial position. Therefore, the conformer with the tert-butyl group in an equatorial position is more stable. When two cyclohexane rings are fused fused rings share two adjacent carbons one ring can be considered to be a pair of substituents bonded to the other ring. As with any disubstituted cyclohexane, the two substituents can be either cis or trans. The trans isomer (in which one substituent bond points upward and the other downward) has both substituents in the equatorial position. The cis isomer has one substituent in the equatorial position and one in the axial position. Trans-fused rings, therefore, are more stable than cis-fused rings.