Problem #51- page 115 in Bruice
In order to solve this question, we need to define if the
substituents are on the same side (cis) or on the opposite side (trans). If the
bonds which hold the substituents are both pointing upwards or downwards, then
we can conclude that the compound is cis. However, if one of the bonds that
holds the substituent points up and the other down, or vice versa, then the
compound is trans. Looking at all four compounds, it is clear that C and D are
cis isomers because in C, both the substituents point downwards, and in D, both
substituents point upwards. If the question had asked for trans isomers, then A
and B would be correct for trans isomers because the substituents point in
directions.
Bruice,Paula Y. “An Introduction to Organic Compounds.”
Organic Chemistry.Ed.Nicole Folchetti.Boston:Prentice Hall,2011. 115
I actually thought that the terms cis and trans referred to the hydrodens pointing up and down and not the substituents. This was seriously one of the hardest concepts this year for me along with the E and Z concept.
ReplyDeleteVery nice explanation, you made it sound easy which it is not. With the chair structure figuring out cis and trans can get a little confusing.
ReplyDelete