Newman Projections: Rotate
Rotating about a C–C single bond changes only the conformation: the front and back groups keep their identities while their dihedral relationship changes.
Rotate the front and back carbons until the Newman projection matches the wedge-dash structure.
Common Questions
What is a Newman projection?
A Newman projection shows the conformation of a molecule by looking straight down the axis of a carbon-carbon bond. The front carbon is a dot, the back carbon is a circle, and each carbon's three substituents radiate outward at 120-degree angles.
How do you rotate a Newman projection?
Rotating the front carbon turns its three substituents while the back carbon's substituents stay fixed (or vice versa). A 60-degree rotation converts between staggered and eclipsed conformations.
How do Newman projections relate to wedge-dash structures?
A wedge-dash structure shows 3D arrangement from the side. A Newman projection shows the same molecule looking down one bond axis. Each group stays on the carbon it is bonded to, and the wedge or dash tells you which side of that carbon it sits on.
What is a dihedral angle?
A dihedral (torsion) angle is the angle between two substituents on adjacent carbons, as viewed in a Newman projection. Anti = 180 degrees, gauche = 60 degrees, eclipsed = 0 degrees.