Lesson 6 Flashcards
The most Stable Alicyclic isomers
Staggered
The least stable alicyclic isomers
Eclipsed
How to calculate the bond angle
180 - 360/n
What happens when all H atoms are eclipsed
there will be a steric effect and the isomer becomes unstable
What happens when angle are stable
decrease in orbital overlap
C-C bond weakens
Good overlap
decrease overlap
True or False: the planar isomer of a cycloalkane is stable
False, planar isomers are unstable since cycloalkanes are typically not flat
True or False: Cyclopropane is always planar
true
Most stable conformation of Cyclobutane
fourth carbon is below to move away from eclipsed conformation
Most stable conformation of cyclopentane
Puckered envelope conformation, where fifth carbon does not lie on the same plane
Most stable conformation of cyclohexane
Chair conformation
Least stable conformation of cylcohexane
Half chair, since it has the higehst energy
Are chair isomers the same compound?
yes, since it is simply interconvertible through the ring flip
Can chair isomers be separated in the lab?
No, since they are the same compound with the same chemical and physical properties, there is no way to separate the isomers
True or False: Axial is more stable than equatorial
False, Axial makes substituent parallel to hydrogen which leads to steric strain
True or False: Cis and trans isomers are the same compound
False, they are different compounds since they are not interconvertible
