Isomery Flashcards
What is isomery/isomers?
Isomery is the presence of isomers
Isomers are molecules that share the exact same formula with each other but are arranged differently
What are the two main types of isomery?
structural/planar and spatial
What are the two sub-categories of spatial isomery?
Geometric: Isomers differ in their spatial arrangement about a double bond.
Optical: Isomers differ in the arrangement of atoms in 3D space which create mirror images of each other
What are the two sub-categories of geometric isomery and their definitions?
Cis isomery: when the highest priority functional groups within a molecule all lay on one side of the reference axis
Trans isomery: when the highest priority functional groups lay on OPPOSITE sides of the reference axi
What is the central piece of optical isomery?
The chiral carbon, also called the chiral center or asymetric center
What are the three characteristics of a chiral carbon?
It must be SP3 (tetrahedral) and must be attached to four UNIQUE groups, they cannot be the same.
Furthermore, chiral carbons with equal groups but of different isomery cannot be superimposed onto one another
What are the two classifications of light bending as a result of optical isomery?
Dextrógiro: Luz desviada para a direita
Levógiro: Luz desviada para a esquerda
How to find the amount of optical isomers in a molecule
Isomers = 2^n
Where n = number of chiral carbons in the molecule
Optically inactive isomers are always half the total number of isomers
What is a mesocompound and how can they be accounted for?
Mesocompounds are spatial isomers with two or more equal chiral centers that cancel each other out (optically inactive). Since they are both the same, there is only one optically inactive arrangement for any pair of equal chiral centers.
