Ethyl 3-mercaptobutyrate - ≥95% , CAS No.156472-94-5

CAS: 156472-94-5 Cat. No.: E1064997 Fórmula: C₆H₁₂O₂S Peso molecular: 148.22 Número EC: 435-460-5

GRADE & PURITY ≥95%

Storage

Store at 2-8°C,Protected from light,Argon charged

Shipped In

Wet ice

Specifications

Especificaciones y pureza

≥95%

Condiciones de almacenamiento de almacenamiento

Store at 2-8°C,Protected from light,Argon charged

Enviado en

Wet ice

Este producto requiere envío en cadena de frío. Los servicios terrestres y otros servicios económicos no están disponibles.

Pureza

≥95%

Nombres e identificadores

• Sonrisas canónicas: CCOC(=O)CC(C)S
• IUPAC Name: ethyl 3-sulfanylbutanoate
• InChIKey: FPBCNQQYLDBWMH-UHFFFAOYSA-N
• INCHI: 1S/C6H12O2S/c1-3-8-6(7)4-5(2)9/h5,9H,3-4H2,1-2H3
• Peso molecular: 148.22

Taxonomic Classification

Taxonomy Tree

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

• Kingdom: Organic compounds
• Superclass: Lipids and lipid-like molecules
• Clase: 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 Alkylthiols 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 - Alkylthiol - Organic oxygen compound - Organic oxide - Hydrocarbon derivative - Organosulfur compound - Organooxygen compound - Carbonyl group - Aliphatic acyclic compound
• Descripción: 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

Propiedades químicas y físicas

• Sensibilidad: Light sensitive；Air sensitive；Moisture sensitive
• Peso molecular: 148.230 g/mol
• XLogP3: 1.100
• Hydrogen Bond Donor Count: 1
• Hydrogen Bond Acceptor Count: 3
• Rotatable Bond Count: 4
• Exact Mass: 148.056 Da
• Monoisotopic Mass: 148.056 Da
• Topological Polar Surface Area: 27.300 Ų
• Heavy Atom Count: 9
• Formal Charge: 0
• Complexity: 93.100
• Isotope Atom Count: 0
• Defined Atom Stereocenter Count: 0
• Undefined Atom Stereocenter Count: 1
• 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

Not applicable. No validated bioassay protocols (e.g., WB, IHC, IF, FC) are associated with this small-molecule reagent in the Product Data. For synthetic applications, see the Reaction Conditions and Synthetic Utility sections for general laboratory guidance.

Biological Roles

This compound is a small synthetic aliphatic ester bearing a thiol; it is not a native metabolite or buffer component.

• General biochemical considerations (literature)

  • Thiols in biology commonly exist as cysteine or glutathione; low-molecular-weight aliphatic thiols can undergo oxidation to disulfides and react with electrophilic biomolecules.
  • Esters are susceptible to enzymatic hydrolysis (esterases) in biological systems, which would convert this reagent to 3-mercaptobutyric acid and ethanol; the free acid could further participate in standard thiol redox chemistry.

• Laboratory biology interface (non-clinical)

  • In chemical biology or materials contexts, the thiol can serve as a handle for thiol–maleimide or thiol–ene conjugations to biomolecules or surfaces; however, this compound is not tailored for bioconjugation selectivity or aqueous stability.

No specific endogenous role, receptor interaction, or pathway is attributed to Ethyl 3-mercaptobutyrate. For all biological experiments, ensure appropriate containment due to odor and potential irritancy, and limit exposure of cell systems given the reactivity of free thiols with proteins. Research use only.

Buffer Applications

Not typically applicable. Ethyl 3-mercaptobutyrate is a non-ionic organic reagent (ester/thiol) and does not serve as a buffering agent.

• Practical note: If used in aqueous or biphasic reactions, select an external buffer appropriate to your chemistry (e.g., NaHCO3/Na2CO3 for mild basic conditions during S-alkylation workups, phosphate buffers for controlled pH during conjugation chemistry). Avoid strongly oxidative buffers that could convert the thiol to disulfide.

Green Alternatives

While Ethyl 3-mercaptobutyrate itself is the reagent of interest, greener choices can be made around solvents, bases, and processing to minimize environmental impact and odor.

• Greener media for common transformations (general)

  • Replace DCM with EtOAc or 2-MeTHF for coupling and S-alkylation steps when solubility allows.
  • Substitute DMF/DMSO with MeCN, propylene carbonate, or Cyrene (dihydrolevoglucosenone) for polar aprotic needs, noting reactivity and workup differences.
  • Favor alcohols (EtOH) or water/EtOH mixtures for thia-Michael additions; phase-transfer catalysis can enable biphasic aqueous systems.

• Base and catalyst choices

  • Use carbonate bases (K2CO3, Cs2CO3) instead of strong hydrides when feasible to reduce hazard and improve selectivity.
  • Organocatalysts (e.g., DBU, TBD) in low loadings can replace heavy-metal catalysts for Michael additions.

• Odor and emissions control

  • Implement closed reactors, cold traps, and activated carbon venting to capture thiol vapors.
  • Minimize open transfers; use Luer-lock syringes/valved septa to reduce fugitive emissions.

• Comparison (illustrative)

  • DCM vs EtOAc: EtOAc is biodegradable, lower toxicity; may require larger volumes but simplifies waste classification.
  • DMF vs MeCN/2-MeTHF: MeCN is less persistent; 2-MeTHF from renewable sources offers good solvency for S-alkylation and easier separations from aqueous phases.

Trade-offs: Some green solvents alter rates/selectivities or require different bases. Validate on small scale before adoption.

Pharmaceutical Uses

No pharmacopeial or excipient status is provided for this item; it is supplied for research use only.

• General context (non-clinical)

  • Sulfur-containing esters can appear in flavor/fragrance R&D or as intermediates en route to APIs/auxiliaries, but this specific item has no stated pharmaceutical grade or GMP status.
  • The free thiol can be a liability in drug product environments due to odor, oxidation, and potential for protein reactivity; transformations to amides or protected thiols are more typical in medicinal chemistry.

• If considering pre-formulation or medicinal chemistry screening

  • Verify identity/purity by in-house QC (GC, NMR) and assess stability (oxidation to disulfide; ester hydrolysis).
  • Avoid clinical/diagnostic use. For any regulated applications, source material with documented GMP and pharmacopeial compliance.

Physical Properties

• Item-specific values

  • Appearance: 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.

• Literature/general reference values (not product specifications)

  • Approximate molecular formula (literature): C6H12O2S
  • Approximate formula weight (literature): ~148.23 g/mol
  • Physical state: Expected liquid at ambient temperature (typical for short-chain alkyl esters and thiols).
  • Boiling point: Not firmly established; small aliphatic thiol esters of this size often boil in the 170–210 °C range at 1 atm (literature trend; verify experimentally for this compound).
  • Melting point: Typically below 0 °C for analogous compounds (literature trend).
  • Density (20–25 °C): Often in the 0.95–1.05 g/mL range for similar sulfur-containing esters (literature trend).
  • Refractive index (nD20): Commonly ~1.45–1.50 for small esters/thiols (literature trend).
  • Solubility: Expected to be miscible with many organic solvents (Et2O, DCM, EtOAc, MeOH, hexanes) and sparingly soluble in water due to ester and thio functionality (general chemistry expectation).
  • LogP: Small aliphatic esters bearing thiols often show moderate hydrophobicity (estimated logP ~1.5–2.0; literature estimation tools).

Note: Use these literature values only as planning guides. Do not treat them as specifications. For precise values applicable to this catalog item, consult the CoA/Spec Sheet.

Quality and Grades

• Item-specific details

  • Grade/Purity: Not specified for this item; refer to CoA/Spec Sheet.
  • Stabilizers/Inhibitors: Not specified for this item; refer to CoA/Spec Sheet.

• Interpreting common grades (general guidance)

  • Research or Reagent Grade: Suitable for most synthetic applications; typical control of common impurities but not necessarily low-UV or trace-metal qualified.
  • High-purity or GC/HPLC Grade (if applicable): Tighter control of volatile and UV-active impurities; useful if using analytical detection or odor-critical applications. Confirm UV cutoff and impurity limits on the CoA.

• Thiol-specific quality considerations (general)

  • Oxidation state: Thiols can oxidize to disulfides on storage. Review CoA for S–S content and ensure inert handling if critical.
  • Residual solvents and moisture: Moisture accelerates hydrolysis and affects S-alkylation chemistry; Karl Fischer and GC residuals are often reported on CoA (item-specific data not provided here).
  • Odor purity: Trace high-odor impurities can disproportionately impact sensory work; consider fresh material and tight headspace control.

• Recommendations

  • Upon receipt, check the CoA for assay, GC purity profile, residual solvents, and peroxide/oxidation markers if reported.
  • If your use is odor- or analytical-critical, consider performing an incoming GC-FID/GC-MS check and, if needed, short-path distillation under reduced pressure immediately before use.

Reaction and Applications

Ethyl 3-mercaptobutyrate is a versatile bifunctional synthon featuring a nucleophilic thiol and a latent carboxylate (as an ethyl ester). Typical uses include:

• S-alkylation and thioether synthesis (general literature)

  • Convert to thiolate (e.g., K2CO3 or NaH in acetone/DMF) and react with primary alkyl halides, mesylates, or epoxides for linear thioethers bearing an ester handle.
  • Practical note: Keep temperatures moderate (0–25 °C) to minimize competing O-alkylation or ester cleavage.

• Thia-Michael additions

  • The thiol adds to activated alkenes (e.g., acrylates, maleimides, vinyl sulfones) to form C–S bonds under base or radical initiation. The embedded ester facilitates subsequent diversification (hydrolysis, amidation).

• Disulfide chemistry/oxidation-state toggling

  • Controlled oxidation (I2, air/O2 with base, or H2O2 traces) affords disulfides; reduction (DTT, TCEP) can recover thiols. Useful in polymer and surface chemistry.

• Ester functional group interconversions

  • Hydrolysis to 3-mercaptobutyric acid (acid/base conditions). Amidation via activation (EDC/DMAP, DIC) yields thio-bearing amides; transesterification adjusts protecting group patterns.

• Cyclization/annulation strategies

  • Intramolecular thioether formation onto tethered electrophiles to generate sulfur heterocycles (thietanes, thioethers) using the ester as a directing/spacing element.

• Odorant/materials chemistry

  • Sulfur esters are encountered in flavor/fragrance R&D and as reactive monomers for thiol–ene polymerizations (research use only). The ester provides handle for grafting to resins or surfaces after C–S bond formation.

Notes: Maintain an inert atmosphere to suppress thiol oxidation when high selectivity is required. Use freshly opened or distilled material for sensitive transformations.

Reaction Conditions

General literature guidance for transformations involving Ethyl 3-mercaptobutyrate (use as starting point; optimize per substrate):

• S-alkylation (thioether formation)

  • Base: K2CO3 (2–3 eq) or Cs2CO3 in acetone/MeCN at 20–50 °C; or NaH (1.1–1.5 eq) in THF/DMF at 0–25 °C for less reactive electrophiles.
  • Electrophiles: Primary halides/mesylates, benzyl halides, epoxides (ring-opening at less hindered carbon in polar aprotic solvents).
  • Typical times: 1–12 h. Monitor by TLC/GC; quench with NH4Cl.

• Thia-Michael additions

  • Conditions: Base-catalyzed (Et3N/DBU, 5–20 mol%) or photoinitiated (AIBN/UV) in MeCN, EtOH, or 2-MeTHF at 0–25 °C.
  • Michael acceptors: Acrylates, maleimides, vinyl sulfones. Reactions often reach completion within 0.5–4 h.

• Ester hydrolysis and amidation

  • Hydrolysis: 1–2 M NaOH or K2CO3 in MeOH/H2O (1:1) at 0–25 °C affords 3-mercaptobutyric acid; maintain inert atmosphere to limit disulfide formation.
  • Amidation: Activate the acid (post-hydrolysis) using EDC/HOBt or DIC/DMAP in DCM/DMF, 0–25 °C; or use direct aminolysis of the ester with primary amines under heat with catalysts (e.g., Ti(OiPr)4), noting potential thiol side reactions.

• Oxidation to disulfide

  • Mild: I2 (0.5 eq) in MeOH/DCM at 0–10 °C; or air/O2 with base and catalytic Cu salts. Monitor closely to avoid overoxidation to sulfonic derivatives.

Yields vary widely by substrate; for simple S-alkylations, isolated yields of 70–95% are common in literature. Always perform small-scale screens to balance reactivity versus preservation of the ester and thiol.

Safety and Handling

• Item-specific hazard information

  • Signal Word: Not specified for this item; refer to SDS.
  • H-Statements: Not specified for this item; refer to SDS.
  • GHS Classification/Pictograms: Not specified for this item; refer to SDS.

• General safety considerations for thiol-containing esters (literature/good practice)

  • Odor: Low-molecular-weight thiols are strongly odorous; handle in a well-functioning fume hood.
  • Flammability: Many aliphatic esters are flammable liquids. Keep away from ignition sources until specific flash point is confirmed.
  • Irritation/sensitization: Thiols can be skin/eye irritants and may cause sensitization in susceptible individuals.
  • Peroxide formation: Not a classical peroxide former like ethers; however, avoid prolonged air/UV exposure that can lead to oxidative byproducts (e.g., disulfides).
  • Incompatibilities: Strong oxidizers (risk of thiol oxidation), strong bases (can generate thiolate; may accelerate hydrolysis or undesired S-alkylation), strong acids (ester hydrolysis), and reactive metals for the free thiol.

• PPE and handling

  • Wear protective gloves (nitrile), lab coat, and splash goggles. Use in a fume hood.
  • Avoid inhalation and skin contact; promptly contain and clean up spills with absorbent while minimizing odor spread.

• First aid (overview; defer to SDS)

  • Inhalation: Move to fresh air; seek medical attention if symptoms persist.
  • Skin/eye contact: Rinse with plenty of water for at least 15 minutes; remove contaminated clothing; seek medical attention as needed.
  • Ingestion: Rinse mouth; do not induce vomiting; obtain medical attention.

Always consult the product’s SDS for authoritative hazard, exposure limits, and emergency procedures.

Solvent Selection

This product is a reagent/substrate rather than a solvent. Selection here refers to choosing media to dissolve and react Ethyl 3-mercaptobutyrate effectively.

• Polarity and miscibility (general chemistry)

  • Expected to dissolve well in moderately polar and nonpolar organic solvents: EtOAc, THF, DCM, toluene, acetone, MeOH/EtOH, and hexanes.
  • Water solubility is expected to be low to moderate; aqueous-organic biphasic systems (e.g., toluene/NaHCO3 aq) are common for S-alkylation or acylation workflows.

• Choosing solvents by transformation

  • S-alkylation (thiolate formation): Polar aprotic solvents (DMF, DMSO, MeCN, acetone) promote SN2 reactions; milder bases (K2CO3, Cs2CO3) in acetone/MeCN often work well.
  • Thia-Michael additions: Alcohols (MeOH, EtOH), MeCN, or water/EtOH mixed media with base or nucleophilic catalysts (e.g., DBU) facilitate reaction.
  • Ester transformations (hydrolysis, transesterification): Alcoholic solvents for transesterification (with acid/base catalysts); aqueous-organic mixtures for hydrolysis.
  • Amidation via activation (EDC/HOBt, DIC/DMAP): Use DCM, DMF, or MeCN depending on substrate solubility and downstream workup.

• Practical tips

  • Odor control: Prefer closed systems and low-volatility solvents (e.g., MeCN, EtOAc) to reduce headspace odor.
  • Avoid prolonged exposure in strongly basic alcoholic media if the free thiol is to be preserved (risk of oxidation/transesterification).
  • For green chemistry goals, consider 2-MeTHF or EtOAc as replacements for DCM/DMF where feasible (see Green Alternatives).

Storage and Reconstitution

• Item-specific storage

  • Storage Conditions: Room temperature (per Product Data).
  • Shipped In: Not specified for this item; refer to CoA/Spec Sheet.

• General handling recommendations (thiol-containing esters)

  • Store tightly sealed under inert gas (N2 or Ar) to minimize oxidation to disulfide and odor permeation, even if room temperature storage is acceptable.
  • Protect from light and air if long-term storage is anticipated. A desiccated cabinet is preferred to limit hydrolysis.
  • If the material crystallizes or shows phase separation (unlikely for this class but possible due to impurities), gently warm to ambient and homogenize before sampling.

• Reconstitution/use

  • Typically supplied as a neat liquid; no reconstitution required.
  • For solution preparation, use dry, oxygen-free solvents when selectivity is critical (e.g., S-alkylation, Michael additions). Prepare working solutions fresh to limit oxidation.

• Stability notes

  • Free thiols can slowly oxidize; periodic QC (GC, 1H NMR for disulfide signals) is advisable for materials stored >3–6 months.

Always defer to the product’s CoA and SDS for definitive storage and handling instructions. Research use only.

Structure and Identity

Brief description: Ethyl 3-mercaptobutyrate is a sulfur-containing aliphatic ester bearing a free thiol group on the β-position relative to the carbonyl, making it a bifunctional building block (ester + thiol).

• Item-specific (from Product Data)

  • SKU: E1064997
  • Product Name: Ethyl 3-mercaptobutyrate
  • CAS: 156472-94-5
  • PubChem CID: 9833996
  • InChIKey: 88437 (format appears incomplete; verify against CoA/SDS)
  • Storage Conditions: Room temperature
  • Grade/Purity: Not specified for this item; refer to CoA/Spec Sheet.

• Literature/computed identity (for reference; not item-specific specs)

  • Expected molecular formula (literature): C6H12O2S
  • Expected molecular weight (literature): ~148.23 g/mol
  • Typical SMILES (literature): CCOC(=O)CC([SH])C
  • Functional groups: ethyl ester (–CO2Et), thiol (–SH), secondary carbon bearing the thiol (chiral center possible → racemate unless specified).

• Structural features (general description)

  • Linear four-carbon backbone for the butyrate moiety with the thiol on C-3 (β to the carbonyl).
  • The ester portion is ethyl, contributing moderate lipophilicity and typical ester reactivity (hydrolysis, transesterification, amidation via activation).
  • The thiol is nucleophilic and redox-active (can form disulfides). Presence of –SH imparts strong odor typical of low-MW thiols.
  • 2D description: EtO–C(=O)–CH2–CH(SH)–CH3; one stereogenic center at the thiolated carbon; no ring systems; no additional heteroatoms beyond O and S.

Synthetic Utility

Functional handles and reactivity make Ethyl 3-mercaptobutyrate valuable in synthesis:

• Thiol functionality (S–H)

  • Nucleophilic substitution: Formation of thioethers via SN2 on alkyl halides/mesylates. Base selection (K2CO3/Cs2CO3 vs NaH) tunes reactivity and minimizes side reactions.
  • Conjugate additions: Thia-Michael to α,β-unsaturated carbonyls and sulfones; radical thiol–ene additions under UV/initiators create C–S bonds rapidly.
  • Protection/derivatization: Temporary masking as thioacetate, trityl (Trt), or acetamidomethyl (Acm) for multi-step sequences.
  • Oxidation/reduction: Disulfide formation and cleavage enable reversible linking strategies.

• Ester functionality (–CO2Et)

  • Hydrolysis to the carboxylic acid for coupling (EDC/HATU/DIC) to make amides, ureas, or linkers bearing thioethers.
  • Transesterification to alter protecting group patterns or polymerizable esters.
  • α-Functionalization: The methylene α to carbonyl (adjacent to –CO2Et) can participate in enolate chemistry after suitable deprotonation (taking care to avoid S-alkylation/overreaction).

• Retrosynthetic value

  • Serves as a masked 3-mercaptobutyric acid equivalent with an ethyl leaving group after hydrolysis, while the –SH enables rapid diversification early in the route.

• Practical notes

  • Inert atmosphere and anhydrous conditions help preserve thiol integrity and limit ester cleavage.
  • For high-purity thioethers, distill or purify immediately before key steps to remove oxidized/disulfide impurities.

Target Specificity

Not applicable. This product is a small-molecule reagent and is not an antibody, enzyme, or affinity probe. No antigen/epitope specificity, species reactivity, clone, or isotype information applies to this item.