Secondary alcohols
Secondary alcohols connect alcohol oxidation to ketones and Grignard addition to aldehydes.
- Functional group
- R2CHOH
- Also known as
- secondary alcohol
Overview
Alcohols where the carbon bearing OH is attached to two carbon groups.
Secondary alcohols connect alcohol oxidation to ketones and Grignard addition to aldehydes.
A secondary alcohol has two carbon groups on its OH-bearing carbon and is oxidised to a ketone. A cyclic alcohol such as cyclohexanol follows the same local structural rule; belonging to a ring does not make it tertiary.
Identifiers
- Functional group
- R2CHOH
- Also known as
- secondary alcohol
Chemical identifiers
- SMILES
- CC(C)O
Properties
- Local structure
- R-CH(OH)-R′; one hydrogen remains on the carbon that becomes the carbonyl carbon.
- Methyl subgroup
- CH3CH(OH)R can give an iodoform result after oxidation; this does not apply to every secondary alcohol.
Diagnostic tests
acidified dichromate oxidation test
- Reagent
- acidified K2Cr2O7(aq)
- Conditions
- Add aqueous potassium dichromate(VI), acidified with dilute sulfuric acid, to the sample and warm gently in a water bath.
- Positive observation
- the orange solution turns green
- Negative observation
- the solution remains orange
- Interpretation
- A positive result is consistent with a secondary alcohol being oxidised to a ketone.
- Scope
- Secondary alcohols give this oxidation colour change.
- Limitations
- Secondary alcohols, primary alcohols and aldehydes can give this response.
- 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.
- Cyclohexanol
Cyclohexanol is an organic compound with the molecular formula C6H12O.
- L-Malic acid
L-Malic acid is an organic compound with the molecular formula C4H6O5.
- 1-Phenylethanol
A secondary benzylic alcohol formed by reducing acetophenone.
- Cyclopentanol
A secondary alcohol with its hydroxyl-bearing carbon inside a five-membered ring.
Connected reactions
- Oxidation: Secondary alcohols → Ketones
Oxidation of a secondary alcohol gives a ketone.
- Reduction: Ketones → Secondary alcohols
Reduction of a ketone gives a secondary alcohol.
- Carbonyl addition: Grignard reagents → Secondary alcohols
Grignard addition to aldehydes gives secondary alcohols after work-up.
- Grignard addition co reactant: Aldehydes → Secondary alcohols
Aldehydes plus Grignard reagents give secondary alcohols after acidic work-up.
References
- Organic Chemistry: Oxidation of AlcoholsJohn McMurry · OpenStax Organic Chemistry · 2023
Supports functional-group chemistry used to curate the linked examples. Checked 2026-09-16; named examples are applications of textbook scope, without claimed experimental yields.
- 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: Cyclohexanol (CID 7966)National Center for Biotechnology Information · PubChem
Identity, molecular formula, molecular weight and aliases retrieved via PUG REST on 2026-09-08.
- PubChem Compound Summary: L-Malic acid (CID 222656)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.
- PubChem Compound Summary: Cyclopentanol (CID 7298)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.