Unit 4 Flashcards
Aromatic
What does plane polarised mean?
Light usually has electric fields pointing in many directions. If it meets a material that makes it point in one direction it is said to be plane polarised
What does chiral mean? And what does an carbon need in order to be chiral
cannot be superimposed and can rotate plane polarised light. Mirror images. A carbon needs 4 different atoms to bond to it
What is a chiral carbon usually called?
Stereogenic (hasn’t got symmetry)
What is the enantiomorphism?
type of isomerism concerned with chiral molecules
What is the mirror image pair of stereoisomers called?
Enantiomers (two molecules that are mirror images of each other but cant be superimposed)
What do a pair enantiomers have in common
same melting points boiling point nmr mass spectra…
How can you tell a pair of enantiomers apart?
By how they interact with plane polarised light rotates clockwise or anticlockwise . measure with polarimeter
What is a compound which can rotate the plane of polarised light called?/
optically active
What is a racemic mixture?
50% 50% of each enantiomer, it will have no affect on plane polarised light as the affects cancel each other. It is optically inactive
What numbers correspond to ortho meta para?
ortho- 1.2
Meta- 1,3
Para- 1,4
What conditions and reagents are needed to form bromobenzene from benzene?
Bromine and an acid catalyst
Benzene with sulfuric acid and nitric acid gives what?
Nitrobenzene
What is a diastereomer?
A molecule with two stereo-centres
If benzene is mixed with potassium permanganate will happen?
It wont react
What does a methyl substituent do on an aromatic ring?
Activating, ortho and para directing
