Question

1 Name the reagents used in the following reactions:
(i) Oxidation of a primary alcohol to carboxylic acid.
(ii) Oxidation of a primary alcohol to aldehyde.
(iii) Bromination of phenol to 2,4,6-tribromophenol.
(iv) Benzyl alcohol to benzoic acid.
(v) Dehydration of propan-2-ol to propene.
(vi) Butan-2-one to butan-2-ol.​

Answer 1

Answer:

(i) Acidified potassium permanganate

(ii) Pyridinium chlorochromate (PCC)

(iii) Bromine water

(iv) Acidified potassium permanganate

(v) 85% phosphoric acid

(vi) NaBH4 or LiAlH4

Answer 2

Explanation:

(i) Oxidation of a primary alcohol to carboxylic acid.

Acidified K

2 Cr2O7or acidified KMnO 4

(ii) Oxidation of a primary alcohol to aldehyde.

Pyridinium chlorochromate (PCC) in CH

2

Cl 2 or Pyridinimium dichromate (PDC) in CH 2Cl2

(iii) Bromination of phenol to 2,4,6-tribromophenol.

Aqueous bromine ( or bromine water)

(iv) Benzyl alcohol to benzoic acid.

Acidified or alkaline KMnO

4 followed by hydrolysis with dil H 2 SO4

(v) Dehydration of propan-2-ol to propene.

Conc. H

2 SO 4at 443 K

(vi) Butan-2-one to butan-2-ol.

NaBH

4or Ni/H 2