cahn-ingold-prelog rules：Cahn Ingold Prelog Priority Rules (with Examples)

Robert Sidney Cahn, Christopher Kelk Ingold, and Vladimir Prelog came up with a system of nomenclature in 1965, that assigned the names to R-S, cis-trans, and E-Z molecules. The Cahn-Ingold-Prelog set priority rules stated that a group with more atomic number, isotopic priority, secondary position priority (by atomic number), and multiple numbers of bonds can be assigned priority over other functional groups.

CIP priority rules have the following deciding factors;

Atomic numbers Secondary groups Post-secondary groups Isotopic priority Multiple bonds Molecular rotation (arrangement)

This set of nomenclature rules was named after these three scientists namely Cahn, Ingold, and Prelog (CIP) rules.

Why the CIP rules?

Cahn Ingold Prelog (CIP) rules assign the R and S nomenclature configuration to compounds with one stereocenter and E and Z nomenclature to double bonds. This way entire molecules can be uniquely specified by including R/S and E/Z descriptors to the I...