Newman projection

Molecule of butane in syn-clinal (-sc) conformation
Sawhorse projection	Newman projection

A Newman projection, useful in alkane stereochemistry, visualizes chemical conformations of a carbon-carbon chemical bond from front to back, with the front carbon represented by a dot and the back carbon as a circle (see below). The front carbon atom is called proximal, while the back atom is called distal. This type of representation is useful for assessing the torsional angle between bonds.

A Sawhorse representation, on the other hand, views a carbon-carbon bond from an oblique angle. This type of representation makes it easy to visualize the molecule as a whole in 3-D.

Other methods for depicting molecules are the Fischer projection, the Haworth projection and the Natta projection.

This projection is named after Melvin Spencer Newman, an American chemist of Ohio State University who introduced it in 1952.

References

• Newman, M. S. Record. Chem. Progr. (Kresge-Hooker Sci. Lib.) 1952, 13, 111.
• Newman, M. S. A notation for the study of certain stereochemical problems. J. Chem. Educ. 1955, 32, 344-347.

See also

• Haworth projection
• Fischer projection
• Natta projection