Methyl secondary alcohols
Methyl secondary alcohols are oxidised under alkaline iodine to methyl ketones, then cleaved in the iodoform reaction.
- Functional group
- CH3CH(OH)R
- Also known as
- methyl-2-ols, methyl secondary alcohol, CH3CH(OH)R
Overview
Secondary alcohols containing the CH3CH(OH)- motif.
Methyl secondary alcohols are oxidised under alkaline iodine to methyl ketones, then cleaved in the iodoform reaction.
Identifiers
- Functional group
- CH3CH(OH)R
- Also known as
- methyl-2-ols, methyl secondary alcohol, CH3CH(OH)R
Chemical identifiers
- SMILES
- CC(C)O
Diagnostic tests
iodoform test
- Reagent
- iodine in alkaline solution
- Conditions
- Add iodine followed by aqueous alkali and warm gently in a water bath.
- Positive observation
- a pale-yellow precipitate of triiodomethane forms
- Negative observation
- no pale-yellow precipitate forms
- Interpretation
- A positive result supports a methyl secondary alcohol, which is oxidised to a methyl ketone before cleavage.
- Scope
- Alcohols containing the CH3CH(OH)- group give this reaction.
- Limitations
- Not unique to this alcohol class: ethanol, ethanal and methyl ketones also give a positive result.
- Evidence
- textbook core
Related compounds
- Propan-2-ol
A secondary alcohol that oxidises to propanone.
- Butan-2-ol
Butan-2-ol is an organic compound with the molecular formula C4H10O.
- 1-Phenylethanol
A secondary benzylic alcohol formed by reducing acetophenone.
Connected reactions
- Iodoform reaction: Methyl secondary alcohols → Triiodomethane products
Methyl secondary alcohols are oxidised to methyl ketones, then cleaved to triiodomethane and a one-carbon-shorter carboxylate.
References
- Pearson Edexcel International Advanced Level Chemistry Practical GuidePearson Education Limited · Pearson qualifications · 2018
Official Pearson practical guidance for organic qualitative tests, including bromine water, acidified dichromate, silver nitrate, carbonyl reagents and the iodoform reaction.
- PubChem Compound Summary: Propan-2-ol (CID 3776)National Center for Biotechnology Information · PubChem
Identity, molecular formula, molecular weight and aliases retrieved via PUG REST on 2026-09-08.
- PubChem Compound Summary: Butan-2-ol (CID 6568)National Center for Biotechnology Information · PubChem
Identity, molecular formula, molecular weight and aliases retrieved via PUG REST on 2026-09-08.
- PubChem Compound Summary: 1-Phenylethanol (CID 7409)National Center for Biotechnology Information · PubChem
Identity, molecular formula, molecular weight and selected English aliases retrieved via PUG REST on 2026-09-16. Chinese search names are curated nomenclature translations. Unspecified stereochemistry remains unspecified.