Organic: Isomerism Flashcards
Single bonds can freely rotate
True or False?
True
Double bonds can freely rotate
True or False?
False
How do you assign priority to an alkene?
Cut in half, assign priority to highest atomic number in each side
Priority 1 Groups on the same side take the letter Z
True or False?
True
Zame Zide
Groups with Priorities on opposite sides take the letter E
True or False?
True
An isomer with the same connectivity but different geometry is?
A stereoisomer
E.g VSEPR square planar vs tetrahedral
Molecules which can exist as pairs of mirrors images, with the same physical properties but are not superimposable are?
Enantiomers
Pairs of enantiomers have identical physical properties
True or False?
True
Enantiomers must have one chiral carbon
True or False?
True
R and S configuration
Atomic priority
S = anti-clockwise R = clockwise
If a tie, move to next element
Drawing enantiomers
Draw mirror image
Keep bonds the same but invert all stereogenic centres
Why are enantiomers also called optical isomers?
The chiral carbons will rotate the plane of polarised light
What type of isomerism displays structure which aren’t mirror images and are non superimposable
Diastereoisomers
All stereocentres are inverted in a diastereoisomer
True or False?
True/False
Some (not all) are inverted
What is the angle between two substituents on adjacent carbons?
DIHEDRAL ANGLE
180°
