Newman Projections & Chair Conformations Flashcards
What does a wedge represent?
The group is coming towards you
What do the dashes represent?
The group is going away from you
What angle does a Newman projection show?
“birds-eye” / looking down the carbon bonds. It shows the molecules carbon chain from front to back.
Where must the wedges go on a Newman Projection? Dashes?
Wedges go on right side
Dashes go on left side.
What is an eclipse formation on a newman projection?
When the atoms on the back carbon are hidden by the front carbon.
What is more stable - eclipse or staggard?
Staggard is ALWAYS more stable than eclipse.
What is the best way to minimize steric interactions for a Newman projection?
Keep larger atoms way from eachother.
What is a chair conformation?
A 3D view of a cyclohexane.
AN ALKANE RING
Draw a chair conformation with all axial and equatorial lines.
.
What does a wedge translate to in a chair conformation?
an axial or equatorial UP, dependent on which carbon it is on.
What does a dash translate to in a chair conformation?
an axial or equatorial DOWN, dependent on which carbon it is on.
Draw a flipped chair and draw all equatorial and axial lines.
.
What does a ring/chair flip to do the axial/equatorial lines?
Switches them. A group starting axial up will then result in an equatorial up.
THE up/down DOES NOT CHANGE.
*starts up then it ends up
What is the most stable chair conformation?
Larger groups in the equatorial positions. This helps prevent steric interactions.
What is a cis ring?
2 solid wedges or 2 solid dashes. Groups are on the same side
