Chapter 4

Question 1

What is the formula for cycloalkanes?

Answer 1

CnH2n

Question 2

Naming cycloalkanes?(4)

Answer 2

1. cycloalkane usually is base compound
2. number carbons in ring if there is more than one substituent
3. first in alphabet gets lowest number
4. may be cycloalkyl attachment to chain

Question 3

what are the two different substituents on the cyclohexane ring?

Answer 3

axial positions, which are positions parallel to the ring axis
and equatorial positions which are positions are around the ring equator

Question 4

what are configurational isomers?

Answer 4

cis-trans isomers

Question 5

When are two groups cis?

Answer 5

when they are on the same side of the cyclohexane ring(same type of bond wedge) or when one is axial and the other is equitorial on a chair ring

Question 6

when are two groups trans?

Answer 6

when they are on opposite side of the cyclohexane ring(next to each other but have two different types of wedges) or both axial/equitorial on a chair ring

Question 7

which rings are strained and which are most stable?

Answer 7

3- and 4- membered rings are strained and 5- and 6- membered rings are most stable

Question 8

What are stereoisomers?

Answer 8

isomers that have the same order of connections but differ in spatial orientation of the atoms(are connected in same order but differing in 3-D orientation)

Question 9

What is a ring flip?

Answer 9

when different conformations readily interconvert, exchanging axial and equatorial positions , AS WELL AS SHIFT ONE CARBON CLOCKWISE) (what is axial in the starting structure becomes equatorial in the ring-flipped structure and what is equatorial in the starting structure becomes axial after ring-flip)

Question 10

What is true regarding conformational stability of cyclohexanes?

Answer 10

a substituent in the equatorial position is almost always more stable than in an axial position

Question 11

What is polycyclic molecule?

Answer 11

when two or more cycloalkane rings are fused together along a common bond