CHEM 211 Lecture Notes - Lecture 1: Stereocenter, Stereoisomerism, Enantiomer

• School: Queen's University
• Department: Chemistry
• Course: CHEM 211
• Professor: Philip G Jessop

Document Summary

Chirality no mirror plane: no improper axis of rotation, no improper axis of rotation. Look for timescale aspect frozen in position = chiral: four different groups attached to a tetrahedral atom indicates that the molecule may be chiral, amines at room temperature are not chiral. Look for protonation of molecules and what character of each species present. Isomers: compounds that contain the same atoms bonded together in different ways, constitutional isomers different connectivity, stereoisomers same connectivity between atoms. Racemic mixtures: mixture of two enantiomers in equal proportions. If the starting materials of a reaction are achiral, and the products are chiral, they are formed as a racemic mixture of two enantiomers. Enantiomeric excess = how much more of the desired enantiomeric mixture was produced. Chan-ingold-prelog priority rules ***midterm**: looking at the first atoms of each, higher atomic number wins, list atoms attached to the first atom, in order of decreasing atomic number. At the first difference, higher atomic number wins.