Ch 18 Aromatic compounds

Question 1

Phenol

Answer 1

Ph-OH

Question 2

Anisole

Answer 2

Ph-O-CH₃

Question 3

Aniline

Answer 3

Ph-NH₂

Question 4

Benzoic acid

Answer 4

Ph-COOH

Question 5

Benzaldehyde

Answer 5

Ph-COH

Question 6

Acetophenone

Answer 6

Ph-COCH₃

Question 7

Styrene

Answer 7

Ph-CH=CH₂

Question 8

Dimmethyl derivatives of benzene are called

Answer 8

Xylene

Question 9

Huckel’s rule

Answer 9

A compound can only be aromatic if the number of pi electrons in the ring is 2,6,10,14,18 and so on, 4n+2’where n is a while number.

Question 10

Anti aromatic

Answer 10

FIX: Special molecular instability associated with a closed loop of adjacent, parallel, overlapping p orbitals which contains 4n pi electrons (n = 0, 1, 2, 3, etc.)

Question 11

Nonaromatic

Answer 11

Def:: A molecule that is neither aromatic or antiaromatic.

Question 12

Annulenes

Answer 12

Compounds consisting of a single ring containing A fully conjugated pi system

Question 13

Hetercycles

Answer 13

Cyclic compounds containing heteratoms (such as S,N or O)

Question 14

Since the lone pair of pyridine does not participate in resonance or aromaticity , it is free to function as a_____.

Answer 14

Base. Pyridine can function as a base because protonation of the nitrogen atom does no destroy the aromaticity

Question 15

Benzylic position

Answer 15

Any carbon atom attached directly to a benzene ring

Question 16

Toluene

Answer 16

Ph-CH₃

Question 17

Chromic acid (Na₂Cr₂O₇/H₂SO₄,H₂O) will react with ______ but not benzene or alkanes. Draw reaction

Answer 17

Alkylbenzenes are readily oxidized by chromic acid but selectively at the benzylic position,the benzylic position must have a least one proton.

Question 18

Free radical bromination (NBS) of a benzylic position is highly _____________.

Answer 18

Regions selective , bromination occurs primarily at the benzylic position due to resonance stabilization of the intermediate benzylic radical.this reaction is important because it allows us to install a functional group at the benzylic Position which can then be exchanged for a different group

Question 19

Benzylic halide +H₂O—->

Answer 19

Alcohol, benzylic halides undergo SN1 reactions very rapidly since the benzylic carbocations is resonance stabilized

Question 20

When treated with (conc. H₂SO₄ or NaOEt) benzylic halides undergo _______.

Answer 20

Elimination reactions to form alkenes

Question 21

PCC will convert an alcohol to an _____

Answer 21

Aldehyde

Question 22

H₂ followed by Pt/2 atm 25 C will _______ in the presence of an aromatic ring

Answer 22

selectively hydrogenate a vinyl in the presence of an aromatic ring

Question 23

Three equivalents of molecular hydrogen in the presence of nickel at 100 atm,150C will __________ a benzene

Answer 23

Hydrogenate

Question 24

Na,CH₃OH/NH₃ will reduce a benzene will be reduced to _______.

Answer 24

1,4-cyclohexadiene, birch reduction

Question 25

Birch mech

Answer 25

Question 26

Birch reductions will reduce EWG but not_____.

Answer 26

EDG