Ethyl 2-methyl-2,3-butadienoate - ≥95% , CAS No.5717-41-9

CAS: 5717-41-9 Cat. No.: E487154 Formula: C₇H₁₀O₂ Peso molecolare: 126.15 Numero EC: 685-760-7

GRADE & PURITY ≥95%

Synonyms

2,3-Butadienoic acid, 2-methyl-, ethyl ester | SCHEMBL14882820 | Ethyl 2-methyl-2,3-butadienoate | starbld0045906 | DTXSID50453709 | Ethyl 2-methylbuta-2,3-dienoate

Storage

Store at 2-8°C

Shipped In

Wet ice

Specifications

Sinonimi

2,3-Butadienoic acid, 2-methyl-, ethyl ester | SCHEMBL14882820 | Ethyl 2-methyl-2,3-butadienoate | starbld0045906 | DTXSID50453709 | Ethyl 2-methylbuta-2,3-dienoate

Specifiche e purezza

≥95%

Condizioni di conservazione di stoccaggio

Store at 2-8°C

Spedito in

Wet ice

Questo prodotto richiede spedizione a catena fredda. I servizi di terra e altri servizi economici non sono disponibili.

Purezza

≥95%

Nomi e identificatori

Sorrisi canonici

CCOC(=O)C(=C=C)C

InChIKey

QFTBEYHBIFWGHJ-UHFFFAOYSA-N

INCHI

1S/C7H10O2/c1-4-6(3)7(8)9-5-2/h1,5H2,2-3H3

Isomeri SMILES

CCOC(=O)C(=C=C)C

WGK Germania

3

Numero UN

3272

Gruppo di imballaggio

III

Peso molecolare

126.15

Reaxy-Rn

1904377

Reaxys-RN_link_address

https://www.reaxys.com/reaxys/secured/hopinto.do?context=S&query=IDE.XRN=1904377&ln=

Taxonomic Classification

Taxonomy Tree

• Kingdom Organic compounds
  • Superclass Lipids and lipid-like molecules
    • Classe Fatty Acyls
      • Subclass Fatty acid esters

• Kingdom: Organic compounds
• Superclass: Lipids and lipid-like molecules
• Classe: Fatty Acyls
• Subclass: Fatty acid esters
• Intermediate Tree Nodes: Not available
• Direct Parent: Fatty acid esters
• Alternative Parents: Carboxylic acid esters Monocarboxylic acids and derivatives Organic oxides Hydrocarbon derivatives Carbonyl compounds
• Molecular Framework: Aliphatic acyclic compounds
• Substituents: Fatty acid ester - Carboxylic acid ester - Monocarboxylic acid or derivatives - Carboxylic acid derivative - Organic oxygen compound - Organic oxide - Hydrocarbon derivative - Organooxygen compound - Carbonyl group - Aliphatic acyclic compound
• Descrizione: This compound belongs to the class of organic compounds known as fatty acid esters. These are carboxylic ester derivatives of a fatty acid.
• External Descriptors: Not available

Data sources

1. Djoumbou Feunang Y, Eisner R, Knox C, Chepelev L, Hastings J, Owen G, Fahy E, Steinbeck C, Subramanian S, Bolton E, Greiner R, and Wishart DS. ClassyFire: Automated Chemical Classification With A Comprehensive, Computable Taxonomy. Journal of Cheminformatics, 2016, 8:61.

DOI: 10.1186/s13321-016-0174-y

Proprietà chimiche e fisiche

• Punto di infiammabilità (°F): 113 °F
• Punto di infiammabilità (°C): 45 °C
• Peso molecolare: 126.150 g/mol
• XLogP3: 1.000
• Hydrogen Bond Donor Count: 0
• Hydrogen Bond Acceptor Count: 2
• Rotatable Bond Count: 3
• Exact Mass: 126.068 Da
• Monoisotopic Mass: 126.068 Da
• Topological Polar Surface Area: 26.300 Ų
• Heavy Atom Count: 9
• Formal Charge: 0
• Complexity: 152.000
• Isotope Atom Count: 0
• Defined Atom Stereocenter Count: 0
• Undefined Atom Stereocenter Count: 0
• Defined Bond Stereocenter Count: 0
• Undefined Bond Stereocenter Count: 0
• The total count of all stereochemical bonds: 0
• Covalently-Bonded Unit Count: 1

Application Protocols

No biology-specific application protocols (e.g., WB, IHC, IF, FC) apply to this small-molecule reagent. For synthetic applications, consult the Reaction Conditions and Application notes herein and adapt to your substrates, catalysts, and scale.

General lab protocol pointers (chemistry context):

• Verify reagent identity and purity by NMR/GC–MS prior to key experiments.
• Dry solvents and glassware; assemble inert-atmosphere setup when required.
• Run small-scale trials to screen catalysts/solvents and establish quench/workup.
• Document temperature control and addition rates to ensure reproducibility.

Biological Roles

This product is a synthetic organic building block intended for chemical research. It does not have established endogenous biological roles.

• General note: low-molecular-weight ethyl esters and allenoates are not typical biometabolites, and no specific metabolic/signaling function is attributed to this structure in standard biochemical pathways (literature context). Any interactions with biological systems would be incidental and highly context-dependent.

• Research use only: Per Product Data, this item is for research use only and is not intended for diagnostic, therapeutic, or other clinical applications.

Buffer Applications

Not typically applicable. Ethyl 2-methyl-2,3-butadienoate is a hydrophobic organic reagent, not a buffering agent. It is not used to prepare aqueous buffer systems or for pH control. For practical usage details, see Reaction & Applications, Synthetic Utility, and Reaction Conditions sections.

Green Alternatives

There is no direct “green substitute” for the unique reactivity of allenoates in MBH/annulation chemistry. However, greener choices can be made in the ancillary materials and process design.

• Solvent selection (replace chlorinated/air-sensitive media where feasible):

  • Consider ethyl acetate, 2-methyltetrahydrofuran (2-MeTHF), cyclopentyl methyl ether (CPME), or toluene instead of dichloromethane or diethyl ether when compatible with rate/selectivity.
  • Use acetonitrile or ethanol for certain organocatalytic MBH reactions where literature supports comparable outcomes.

• Process intensification:

  • Run at higher substrate concentrations to reduce solvent volumes.
  • Employ flow chemistry to improve heat/mass transfer and reduce solvent waste.

• Workup/purification:

  • Favor liquid–liquid extraction with greener solvents (EtOAc/brine) and minimize silica usage; crystallize downstream derivatives when possible.

• Reagent alternatives (reaction-design perspective):

  • In syntheses not strictly requiring the allenoate manifold, acrylates or enones may serve as more common electrophiles with broader solvent flexibility; acknowledge that this sacrifices the distinctive umpolung and annulation pathways of allenoates.

Comparison (general):

• DCM vs EtOAc: EtOAc offers lower toxicity and renewable feedstock routes; may modestly slow some Lewis acid–mediated steps but is often acceptable.
• THF vs 2-MeTHF: 2-MeTHF is bio-based, higher bp, and less peroxide-prone; drying requirements similar; check catalyst solubility.

Pharmaceutical Uses

No excipient or pharmacopeial role is specified for this item. As an allenoate reagent, it is used in synthetic organic chemistry and methodology development rather than in formulation.

• Formulation/excipient status: Not specified; not typically used as a pharmaceutical excipient.
• Manufacturing relevance: Potential intermediate or building block in discovery-scale synthesis; any GMP or pharmacopeial compliance would require separate qualification not provided for this catalog item.

Refer to your quality system and regulatory guidelines before considering any use beyond research chemistry.

Physical Properties

Item-specific physicochemical specifications (exact numeric specs) are not provided in the Product Data for this SKU.

• Item-specific specs:

  • Appearance: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Density, refractive index, UV cutoff, water/peroxide content: Not specified for this item; refer to CoA/Spec Sheet.

• General/literature expectations for substituted ethyl allenoates (informational only):

  • Physical state: typically colorless to pale-yellow liquid for low-mass allenoates.
  • Boiling point: often in the range of low- to mid-100s °C at ambient pressure for C6–C8 allenoates; exact BP for this specific compound should be verified from primary literature or CoA.
  • Solubility: miscible with most common organic solvents (e.g., dichloromethane, toluene, ethyl acetate, THF); negligible solubility in water (literature, typical for esters with small hydrophobic frameworks).
  • LogP: expected positive logP due to ester and hydrocarbon framework (literature trend).

Notes:

• Treat all values above as general literature guidance for similar structures only; do not use as purchase specifications or in lieu of the item’s CoA. For exact parameters relevant to your method (e.g., refractive index for GC purity tracking), consult the lot-specific documentation.

Quality and Grades

• Item-specific grade/purity: Not specified for this item; refer to CoA/Spec Sheet.

Guidance on typical quality considerations for allenoate reagents:

• Purity profile: For stereosensitive catalysis (e.g., enantioselective cycloadditions or Morita–Baylis–Hillman reactions), residual inhibitors, peroxides, or protic impurities can affect outcomes. Confirm GC/GC–MS purity and water content (Karl Fischer) where relevant. Item-specific numeric limits are not provided here.
• Stabilizers/inhibitors: Allenoates are sometimes supplied without polymerization inhibitors; if any stabilizer is present, it will be listed on the CoA. Absence/presence of stabilizers can influence reaction kinetics in radical or photochemical steps.
• Chromatography suitability: If LC or GC assay is planned, check the UV profile and volatility in the lot documentation. Low-UV backgrounds are essential for HPLC UV detection; these details are not specified for this item.
• Fit-for-purpose testing: For organocatalysis, test a small-scale reaction (e.g., benchmark MBH or cycloaddition) to confirm performance in your catalyst/solvent system. Documented assay conditions are preferable to simple purity numbers.

Always defer to the product’s lot-specific CoA/Spec Sheet for definitive purity, stabilizer content, residual solvent profile, and any metals/ionic impurity information.

Reaction and Applications

Ethyl 2-methyl-2,3-butadienoate is a versatile allenoate electrophile/nucleophile synthon widely used in methodology development and complex-molecule synthesis.

• Morita–Baylis–Hillman (MBH) and aza-MBH reactions (literature): allenoates are privileged Michael acceptors under tertiary amine or phosphine catalysis, furnishing densely functionalized allylic alcohols or amines after subsequent steps. The 2-methyl substituent can modulate reactivity and enhance regioselectivity.
• Nucleophile-catalyzed annulations: under phosphine catalysis (e.g., PPh3, trialkylphosphines), allenoates undergo [3+2], [4+2], and [2+2] annulations with activated alkenes, imines, or enones, providing cyclic scaffolds with high atom economy. The allenoate acts as a 2- or 4-carbon synthon via zwitterionic intermediates.
• Cycloadditions and cascade sequences: Lewis acid–mediated reactions with dienes/dienophiles yield cyclohexenes or cyclobutanes. Central allene substitution affects axial-to-planar chirality transfer and diastereoselection.
• Conjugate additions: soft nucleophiles (thiols, malonates, enamines) add to allenoates to form allylated adducts; subsequent isomerization or trapping enables diverse elaborations.
• Transition-metal catalysis: Pd- or Cu-catalyzed coupling/allylation of allenoates can introduce complexity with control over regio- and chemoselectivity; oxidative difunctionalizations are also known (literature).
• Building-block role: serves as a handle for installing substituted allylic motifs after isomerization/hydrogenation; the ester facilitates downstream acylation, reduction (to alcohols), or amidation.

Practical notes:

• Use dry, oxygen-free conditions to suppress polymerization and isomerization.
• Catalyst loading and base choice dramatically impact regioselectivity (γ- vs α-addition). Conduct small screens.
• Monitor by GC/LC or in situ IR due to potential overlap of allene UV maxima.

Reaction Conditions

The following ranges reflect general literature guidance for allenoates and should be optimized per substrate/catalyst system. They are not item-specific specifications.

• MBH/aza-MBH (tertiary amine catalysis):

  • Catalyst: DABCO, DBU, DMAP, quinuclidine (5–30 mol%).
  • Solvent: MeCN, DCM, THF, or neat.
  • Temperature: 0–25 °C (cooling can improve selectivity with reactive partners).
  • Time: hours to days depending on electrophile; monitor by TLC/GC.

• Phosphine-catalyzed annulations:

  • Catalyst: PPh3 or trialkylphosphines (5–20 mol%).
  • Partner: activated alkenes or imines (1.0–1.5 equiv relative to allenoate).
  • Solvent: toluene, DCM, THF, or EtOAc.
  • Temperature: 0–60 °C; elevated temperatures accelerate formation of zwitterionic intermediates but may broaden product mixtures.

• Conjugate additions (thiols, malonates, amines):

  • Base/catalyst: tertiary amines or weak bases (5–50 mol%).
  • Solvent: DCM, THF, MeCN.
  • Temperature: 0–25 °C.

• Transition-metal-mediated transformations (illustrative):

  • Pd-catalyzed isomerization/allylation: 0.5–5 mol% Pd; toluene or dioxane; 25–80 °C.
  • Cu-catalyzed additions: Cu(I)/NHC or phosphine ligands; THF, toluene; 0–50 °C.

Tips:

• Conduct reactions under inert atmosphere (N2/Ar) to limit oxidation/polymerization.
• Add allenoate slowly to strongly nucleophilic media to avoid runaway exotherms.
• Quench carefully (buffered conditions) to minimize ester hydrolysis; work up at low temperature when selectivity is moisture/acid/base sensitive.

Safety and Handling

• GHS classification (item-specific): Not specified for this item; refer to SDS.
• Signal word / H-statements / pictograms: Not specified for this item; refer to SDS.

General laboratory safety guidance for low-molecular-weight unsaturated esters and allenoates (informational, defer to SDS):

• Likely hazards: flammable liquid/vapor, skin/eye irritation, and respiratory irritation are common for analogous esters; allenoates can be lachrymatory for some users. Confirm actual classification in the SDS before use.
• PPE: safety glasses or goggles, lab coat, appropriate chemically resistant gloves (e.g., nitrile), and use in a certified fume hood to avoid inhalation of vapors.
• Handling:
  • Avoid heat, sparks, and open flames. Employ grounding/bonding when transferring bulk quantities.
  • Keep container tightly closed; limit headspace and air exposure to minimize hydrolysis or slow polymerization.
  • Avoid contact with strong bases and strong acids which can catalyze addition, isomerization, or hydrolysis of the ester.
• Incompatibilities (general): strong nucleophiles/bases (promote Michael-type addition to allenoate), strong oxidants, and moisture for extended periods (ester hydrolysis risk).
• First aid overview: rinse skin/eyes with water for ≥15 min upon contact; move to fresh air if inhaled; seek medical attention if symptoms persist. Refer to SDS for detailed measures.
• Fire-fighting: use CO2, dry chemical, or alcohol-resistant foam. Combustion may release CO/CO2 and acrid fumes.
• Waste: collect organic waste in halogenated or non-halogenated streams as appropriate to the solvent matrix and local regulations.

Solvent Selection

This product is a reactive building block (allenoate ester), not a solvent. Solvent selection therefore refers to media used to dissolve/handle it in synthesis.

• Polarity/miscibility (general expectations): soluble in a wide range of organic solvents such as dichloromethane (DCM), toluene, ethyl acetate, THF, and acetonitrile; poorly soluble in water (literature for analogous ethyl allenoates).
• Choosing a medium by transformation:
  • Organocatalytic MBH/aza-MBH: polar aprotic solvents (e.g., MeCN, DMSO, DMF) or neat conditions can accelerate rates; DCM and THF are common for balancing rate and selectivity.
  • Cycloadditions (e.g., [2+2], [4+2] with dienes under Lewis acids): toluene, DCM, or ether solvents are frequently used to tune exo/endo selectivity and suppress polymerization.
  • Transition-metal catalysis (e.g., Pd, Cu): toluene, THF, dioxane, or MeCN depending on ligand solubility and base.
  • Conjugate additions: DCM or THF with amine/base catalysts; ensure controlled addition to manage exotherms.
• Practical tips:
  • Dry, oxygen-light conditions reduce side reactions (isomerization/hydrolysis). Sparge solvents with N2/Ar when moisture/oxygen-sensitive catalysts are used.
  • For scale-up, choose solvents with higher flash points (e.g., toluene, EtOAc) and consider mixture viscosity for mass transfer.

Always validate solvent choice against your specific catalyst/base and target selectivity; small solvent screens often give outsized improvements for allenoate chemistry.

Storage and Reconstitution

• Storage conditions (item-specific): Store at 2–8 °C. Shipped on wet ice (per Product Data). Protect from heat and direct sunlight. Keep container tightly closed under inert gas if long-term storage is anticipated to limit oxidation and hydrolysis.
• Stability considerations (general for allenoates):
  • Sensitive to strong acids/bases and prolonged moisture exposure (risk of hydrolysis/isomerization/polymerization). Minimize headspace and avoid repeated freeze–thaw cycles of neat material.
  • For extended storage, consider aliquoting under nitrogen/argon in amber vials.
• Reconstitution/handling:
  • Supplied as a neat liquid or solution (appearance not specified). If solidification occurs at low temperature, allow to warm to ambient and mix thoroughly before use.
  • If dilution is needed, use dry, oxygen-free solvents (e.g., toluene, DCM, THF, EtOAc) compatible with your planned reaction.
• Shelf-life and specifications: Not specified for this item; refer to CoA/Spec Sheet and SDS for any additional storage notes and stability testing data.

Research Use Note: For research use only.

Structure and Identity

Ethyl 2-methyl-2,3-butadienoate is an allenoate ester bearing a cumulated diene (allene) adjacent to an ethyl ester. The 2-position (the central allene carbon) is methyl-substituted, increasing substitution at the allene and influencing reactivity and stereochemical outcomes in pericyclic and nucleophile-catalyzed processes.

• Item-specific identifiers (Product Data):

  • CAS: 5717-41-9
  • CID: 11062389
  • InChIKey: 295743 (as provided)
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.

• Structural features (general/literature description):

  • Functional groups: allene (C=C=C) directly α to an ethyl ester (–CO2Et); one methyl substituent on the central allene carbon.
  • Conjugation/polarization: the α,β-unsaturated character of allenoates (vinylogous to the ester) supports nucleophile-addition and pericyclic reactivity; the allene is cumulated, featuring orthogonal π systems.
  • 2D description: an ethyl carboxylate linked to an sp2 α-carbon that is the terminal of a C=C=C unit; the central allene carbon bears a methyl substituent, giving a substituted allene chain terminating in –CH2.
  • Stereochemistry: allenes can be axial-chiral when disubstituted at both termini; here, substitution pattern typically does not confer axial chirality (literature), but can impact diastereoselectivity in reactions.

Synthetic Utility

Key reactivity arises from the cumulated C=C=C adjacent to an electron-withdrawing ester, enabling multiple, tunable reaction modes.

• Functional groups and roles:

  • Allenoate (α,β-unsaturated cumulated system): serves as an activated Michael acceptor and as a 2C/3C/4C synthon under nucleophile catalysis.
  • Ethyl ester: enables downstream transformations (amidation, reduction to alcohols/aldehydes, saponification, decarboxylative variants).
  • 2-Methyl substitution: modulates LUMO energies and sterics, impacting regioselectivity (γ- vs α-addition) and diastereocontrol in annulations.

• Named reactions and modes (literature):

  • Morita–Baylis–Hillman/aza-MBH (tertiary amine or phosphine catalysis).
  • Phosphine-catalyzed [3+2], [4+2], and [2+2] annulations with electron-poor alkenes/imines.
  • Conjugate additions (soft nucleophiles), giving allylated adducts amenable to further elaboration (e.g., cross-couplings after halogenation, olefinations).
  • Isomerization to dienes/allyl esters under Pd or base; hydrogenation to saturated esters.

• Retrosynthetic value:

  • Access to carbo-/heterocycles with contiguous stereocenters.
  • Rapid complexity generation via cascade sequences (addition–cyclization–trapping) using a single allenoate input.

Practical guidance:

• Control moisture and temperature; bases/acids can trigger side reactions (hydrolysis, isomerization).
• Select catalyst and solvent to favor desired regiochemical outcome; screen nucleophile catalyst (e.g., PPh3 vs PBu3) for rate/selectivity trade-offs.

Target Specificity

Not applicable. This product is a small-molecule reagent, not a biological targeting agent (e.g., antibody, enzyme inhibitor with defined biomolecular target for this catalog entry). No antigen/epitope, species reactivity, clone, or isotype information applies.