organic Ichem exam 2

IR ~1500

ring

IR ~1700

C=O

IR ~1600

C=C

enantiomers

mirror images but not superimposable

diastereomers

non mirror images non superimposable

increased freq due to: (bonds)

less bonds

specific rotation (for chiral and conc)

higher the concentration, the greater the rotation

specific rotation equation

=observed rotation/(conc (g/mL) * path length (dm))

specific rotation enantiomers

same extent but opposit

stereoisomers

cis and trans (is the substituent flipped)

cis and trans diastereomers

flipped bonds

change in absorbance due to more e-neg atoms

C+/O- is less likely as the e-neg pulls the atoms towards it

makes it more stable (preferred res structure)

appears at higher wave lengths

Enantiomeric excess (ee)

measure of purity

how much of one enantiomers is in the mixture compared to the other

Enantiomeric excess (ee) formula

ee = specific rotation/observed rotation

Enantiomeric excess (ee) optical rotation formula

ee% = 100 x optical rotation

Enantiomeric excess (ee) percent formula

ee% = %major enantiomer - %minor enantiomer

Stronger bonds will be found

higher wave numbers

chirality

a molecule that is not superimposable on its mirror image

heavier molecules will be found at

lower wave numbers