Eschenmoser–Claisen rearrangement
E398759
The Eschenmoser–Claisen rearrangement is a variant of the Claisen rearrangement in organic chemistry that converts allylic alcohols and amides into γ,δ-unsaturated carbonyl compounds via a [3,3]-sigmatropic rearrangement.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Eschenmoser–Claisen rearrangement canonical | 3 |
How this entity was disambiguated
This entity first appeared as the object of triple T3935407 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Eschenmoser–Claisen rearrangement Context triple: [Albert Eschenmoser, knownFor, Eschenmoser–Claisen rearrangement]
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A.
Barton reaction
The Barton reaction is an organic photochemical transformation that converts nitrite esters into δ-nitroso alcohols via intramolecular hydrogen abstraction and radical rearrangement.
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B.
Barton–McCombie deoxygenation
Barton–McCombie deoxygenation is an organic chemistry reaction that converts alcohols into the corresponding hydrocarbons via radical-mediated removal of the hydroxyl group.
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C.
Buchwald–Hartwig amination
The Buchwald–Hartwig amination is a palladium-catalyzed cross-coupling reaction that forms carbon–nitrogen bonds by coupling aryl (or vinyl) halides with amines, widely used in the synthesis of pharmaceuticals and fine chemicals.
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D.
Suzuki coupling
Suzuki coupling is a widely used palladium-catalyzed cross-coupling reaction that forms carbon–carbon bonds between organoboron compounds and organic halides, fundamental in organic synthesis and pharmaceutical chemistry.
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E.
Sharpless epoxidation
Sharpless epoxidation is a landmark asymmetric oxidation reaction in organic chemistry that enables the enantioselective conversion of allylic alcohols to epoxides using chiral catalysts.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Eschenmoser–Claisen rearrangement Target entity description: The Eschenmoser–Claisen rearrangement is a variant of the Claisen rearrangement in organic chemistry that converts allylic alcohols and amides into γ,δ-unsaturated carbonyl compounds via a [3,3]-sigmatropic rearrangement.
-
A.
Barton reaction
The Barton reaction is an organic photochemical transformation that converts nitrite esters into δ-nitroso alcohols via intramolecular hydrogen abstraction and radical rearrangement.
-
B.
Barton–McCombie deoxygenation
Barton–McCombie deoxygenation is an organic chemistry reaction that converts alcohols into the corresponding hydrocarbons via radical-mediated removal of the hydroxyl group.
-
C.
Buchwald–Hartwig amination
The Buchwald–Hartwig amination is a palladium-catalyzed cross-coupling reaction that forms carbon–nitrogen bonds by coupling aryl (or vinyl) halides with amines, widely used in the synthesis of pharmaceuticals and fine chemicals.
-
D.
Suzuki coupling
Suzuki coupling is a widely used palladium-catalyzed cross-coupling reaction that forms carbon–carbon bonds between organoboron compounds and organic halides, fundamental in organic synthesis and pharmaceutical chemistry.
-
E.
Sharpless epoxidation
Sharpless epoxidation is a landmark asymmetric oxidation reaction in organic chemistry that enables the enantioselective conversion of allylic alcohols to epoxides using chiral catalysts.
- F. None of above. chosen
Statements (44)
| Predicate | Object |
|---|---|
| instanceOf |
Claisen rearrangement variant
ⓘ
[3,3]-sigmatropic rearrangement ⓘ organic reaction ⓘ |
| application |
natural product synthesis
ⓘ
stereocontrolled C–C bond formation ⓘ synthesis of γ,δ-unsaturated carbonyl building blocks ⓘ |
| bondCleavage | C–O bond cleavage in imidate or amide acetal ⓘ |
| bondFormation | new C–C bond at γ-position ⓘ |
| bondReorganization | [3,3]-sigmatropic shift ⓘ |
| category | named reaction in organic chemistry ⓘ |
| conditions | thermal conditions ⓘ |
| developedBy | Albert Eschenmoser ⓘ |
| drivingForce | formation of conjugated carbonyl system ⓘ |
| field | organic chemistry ⓘ |
| governingRules |
Woodward–Hoffmann rules for pericyclic reactions
ⓘ
linked to:
Woodward–Hoffmann rules
|
| keyIntermediate |
amide acetal
ⓘ
imidate ester ⓘ |
| limitation | requires formation of suitable imidate or amide acetal precursor ⓘ |
| mechanism | concerted pericyclic process ⓘ |
| namedAfter | Albert Eschenmoser ⓘ |
| notation | [3,3]-sigmatropic rearrangement of imidates or amide acetals ⓘ |
| product |
γ,δ-unsaturated amides
ⓘ
γ,δ-unsaturated carbonyl compounds ⓘ γ,δ-unsaturated esters ⓘ |
| reactionClass |
Claisen-type rearrangement
ⓘ
linked to:
Ireland–Claisen rearrangement
|
| reactionType |
pericyclic reaction
ⓘ
sigmatropic rearrangement ⓘ |
| relatedTo |
Claisen rearrangement
ⓘ
Ireland–Claisen rearrangement ⓘ Johnson–Claisen rearrangement ⓘ
linked to:
Claisen rearrangement
Overman rearrangement ⓘ |
| scope | broad range of allylic substrates ⓘ |
| selectivity | predictable regiochemistry ⓘ |
| startingMaterial |
allylic alcohol-derived amides
ⓘ
allylic alcohol-derived imidates ⓘ allylic alcohols ⓘ allylic amides ⓘ |
| stereochemicalOutcome | chirality transfer from allylic center ⓘ |
| stereochemistry | stereospecific rearrangement ⓘ |
| thermodynamicFeature | irreversible under typical conditions ⓘ |
| transitionState | six-membered cyclic transition state ⓘ |
| usesReagent |
N,N-dialkylformamides or related amide acetals
ⓘ
orthoformates or formamides to generate imidates ⓘ |
| yearDescribedApprox | 1960s ⓘ |
How these facts were elicited
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Instruction
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Input
Subject: Eschenmoser–Claisen rearrangement Description of subject: The Eschenmoser–Claisen rearrangement is a variant of the Claisen rearrangement in organic chemistry that converts allylic alcohols and amides into γ,δ-unsaturated carbonyl compounds via a [3,3]-sigmatropic rearrangement.
Referenced by (3)
Full triples — surface form annotated when it differs from this entity's canonical label.