4,4′-Dimercaptostilbene is a dithiol molecule that can be coated on gold (Au) surfaces as it provides a rigid structure and has low susceptibility to chemical interactions. It modifies the surface of gold and enables an increase in enhancement factor (EF) for surface enhanced Raman spectroscopy.
This compound belongs to the class of organic compounds known as stilbenes. These are organic compounds containing a 1,2-diphenylethylene moiety. Stilbenes (C6-C2-C6 ) are derived from the common phenylpropene (C6-C3) skeleton building block. The introduction of one or more hydroxyl groups to a phenyl ring lead to stilbenoids.
External Descriptors
Not available
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.
Certificados (CoA, COO, BSE/TSE y tabla de análisis)
C of A & Other Certificates(BSE/TSE, COO):
Analytical Chart:
Propiedades químicas y físicas
Peso molecular
244.400 g/mol
XLogP3
4.500
Hydrogen Bond Donor Count
2
Hydrogen Bond Acceptor Count
2
Rotatable Bond Count
2
Exact Mass
244.038 Da
Monoisotopic Mass
244.038 Da
Topological Polar Surface Area
2.000 Ų
Heavy Atom Count
16
Formal Charge
0
Complexity
197.000
Isotope Atom Count
0
Defined Atom Stereocenter Count
0
Undefined Atom Stereocenter Count
0
Defined Bond Stereocenter Count
1
Undefined Bond Stereocenter Count
0
The total count of all stereochemical bonds
1
Covalently-Bonded Unit Count
1
Calculadoras de soluciones
Molarity Calculator
Determine the necessary mass, volume, or concentration for preparing a solution.
Dilution Calculator
Determine the dilution needed to prepare a stock solution.
Reconstitution Calculator
Reseñas
Reseñas de cliente
Application Protocols
No application protocols are specified for this catalog item. The following general-purpose outlines are provided for typical uses of aromatic dithiols; adapt to your system and consult primary literature.
A. Gold SAM preparation (outline):
Substrate cleaning: Use lab-approved method (e.g., UV–ozone 15–30 min). Handle with clean tools.
Solution: 0.5 mM thiol in absolute ethanol; filter (0.2 µm PTFE). Optional: Degas with N2 for 10 min.
Incubation: Immerse substrate 12–18 h at room temperature, dark.
Rinse/dry: Rinse with ethanol and briefly sonicate; dry under N2.
Characterization: Contact angle, ellipsometry, XPS, or IRRAS.
B. Thiol–ene coupling (outline):
Combine thiol (1.0 equiv –SH), alkene (1.2–2.0 equiv), photoinitiator (1–3 mol%), and solvent (MeCN or EtOAc). Degas by sparging.
Irradiate under 365–405 nm LEDs, 0.5–3 h, monitoring by TLC/LC-MS.
Workup via solvent removal and silica gel purification.
C. S‑alkylation to thioethers (outline):
Suspend thiol in dry DMF; add K2CO3 (2.5–3.0 equiv/–SH). Cool if exothermic.
Add alkyl bromide (1.2–1.5 equiv/–SH). Stir 2–16 h at rt.
Quench with water, extract with EtOAc, wash, dry, concentrate; purify by chromatography.
Note: These are general literature-style guides; they are not validated SOPs for this specific product.
Biological Roles
This molecule is a synthetic aromatic dithiol and is not known as a natural metabolite. No biological function is specified for this product; the following are general considerations relevant to thiol-containing compounds in biochemical contexts.
Redox chemistry: Thiols participate in reversible redox cycles (thiol/disulfide exchange). While endogenous systems primarily involve cysteine/cystine, synthetic dithiols can interact with disulfide bonds under certain conditions, a property exploited in biomaterials and surface passivation.
Surface biointerfaces: Aryl dithiols are used to form SAMs on gold that can be further functionalized with biomolecules (e.g., via maleimide–thiol chemistry or EDC/NHS coupling after installing appropriate terminal groups). The conjugated stilbene spacer offers structural rigidity that can affect protein adsorption and orientation on surfaces.
Fluorescence/photophysics: Stilbene scaffolds often display UV-induced E/Z isomerization and fluorescence; derivatization of the thiols enables probes or photoresponsive surfaces. Specific photophysical parameters for 4,4′-dimercaptostilbene are not provided here.
Biocompatibility: Not specified for this item; any biological exposure/use should be evaluated empirically. Handle strictly as a research chemical.
Research Use Note (from Product Data): For research use only. Not for use in humans or clinical diagnostics.
Buffer Applications
This product is a hydrophobic aromatic dithiol and is not typically employed as a buffering agent. It has low expected water solubility and no defined acid/base pair appropriate for maintaining pH in aqueous systems.
Practical note:
If used in biochemical workflows (e.g., surface modification prior to buffer-based assays), prepare stock solutions in compatible organic solvents (e.g., ethanol, DMF, DMSO) and introduce into aqueous buffers via dilution, co-solvent strategies, or surface-immobilization steps. Validate that residual organic content is acceptable for your system.
For true buffer preparation (pH control), choose established buffering agents (e.g., phosphate, HEPES, Tris) with well-characterized pKa values and buffering ranges.
Green Alternatives
Greenness considerations revolve around solvent choice, odor/toxicity of thiols, and lifecycle of metal-binding ligands.
Opportunities for greener practice (literature/general):
Solvents: Replace chlorinated solvents (DCM, CHCl3) with safer alternatives where feasible.
Odor/toxicity: Consider handling strategies (closed systems, scavengers) to reduce thiol emissions; where chemistry allows, use protected/disulfide precursors that release thiol in situ.
Energy: Many surface-assembly and thiol–ene processes proceed at ambient temperature and can leverage photochemistry with LEDs to reduce energy and improve selectivity.
Comparison examples (general guidance):
Topic: Solvent for SAM formation
Conventional: Ethanol (green) or THF (less green).
Greener option: Ethanol or isopropanol remain preferred for SAMs due to low toxicity/biodegradability, with careful waste segregation.
Topic: Thiol–ene coupling
Conventional: DCM or toluene with radical initiators (AIBN).
Greener option: Acetonitrile or ethyl acetate; photoinitiation using visible-light photoredox catalysts or Type I photoinitiators with LED sources.
Topic: Surface ligand exchange on AuNPs
Conventional: DMF/DMSO (effective but problematic for EHS).
Greener option: Aqueous–alcohol mixtures when colloidal stability allows, or 2-MeTHF/EtOAc for organic-phase exchanges.
Trade-offs:
Aqueous systems reduce VOCs but may not solubilize hydrophobic aryl dithiols; co-solvents or surfactants may be necessary.
Protected/disulfide forms mitigate odor but add synthetic steps and may require reductants (e.g., TCEP, DTT), impacting waste profile.
Pharmaceutical Uses
No pharmacopeial monograph or excipient role is specified for this item. 4,4′-Dimercaptostilbene should be treated as a research chemical intended for laboratory use.
Surface modification: Aryl dithiols can functionalize gold surfaces used in biosensors or analytical devices that may interface with pharmaceutical analytics (e.g., SPR chips), enabling subsequent ligand immobilization.
Redox-responsive materials: The reversible thiol/disulfide chemistry can be incorporated into polymer networks for controlled-release matrices in research; any translation to regulated products would require extensive safety and quality assessment.
Linker chemistry: The bifunctional –SH groups can be transformed into thioethers or further elaborated into maleimide/iodoacetamide-reactive handles for bioconjugation workflows conducted under GMP-like analytical controls in later development — this item itself is not specified for GMP use.
Compliance note:
No medical or therapeutic claims are made. For any use related to pharmaceutical manufacturing or diagnostics, verify specifications (purity, residual solvents, elemental impurities) on the CoA and qualify per your internal quality system.
Physical Properties
Item-specific specifications (this product):
Appearance: Not specified for this item; refer to CoA/Spec Sheet.
Molecular Formula: Not specified for this item; refer to CoA/Spec Sheet.
• Informational (literature/structure-based): C14H12S2
Molecular Weight: Not specified for this item; refer to CoA/Spec Sheet.
• Informational (computed for C14H12S2): ~244.36 g/mol
Storage Conditions (from Product Data): Room temperature
Shipping: Not specified for this item; refer to CoA/Spec Sheet.
Literature/general physicochemical notes for aryl dithiols of this type:
Phase: Typically a crystalline solid or low-melting solid; exact mp/bp for this CAS not located in standard references consulted (literature not readily available).
Solubility: Poorly soluble in water; soluble in common organic solvents (e.g., ethanol, THF, acetone, dichloromethane, DMF, DMSO) — qualitative, literature-general for aryl thiols.
Acidity: Aryl thiols are weakly acidic; typical pKa for para-substituted thiophenols ~6.5–7.2 (literature range, compound-specific value not confirmed).
LogP: Conjugated aryl dithiols are generally hydrophobic (positive logP); specific value for this compound not located.
Optical properties: Conjugated stilbene core often displays UV absorption in the near-UV; exact UV–vis maxima for this compound not located.
Important note: Where exact numerical specifications (mp, bp, density, UV cutoff, metals, residual solvents, etc.) are required for method validation or materials qualification, rely on the item’s CoA/Spec Sheet.
Quality and Grades
Item-specific quality information:
Grade/Purity: Not specified for this item; refer to CoA/Spec Sheet.
Appearance: Not specified for this item; refer to CoA/Spec Sheet.
How to interpret grades (general guidance for materials science/reagent chemicals):
Research grade indicates suitability for R&D and prototyping. Purity is typically expressed as area% (GC/HPLC) or assay% (qNMR/elemental), and residual metals/solvents are provided where relevant.
High-purity materials for surface science (e.g., formation of self-assembled monolayers on Au) often require additional controls: low disulfide content, low non-volatile residue (NVR), and defined isomeric purity (E/Z for stilbene core when relevant).
Stabilizer-free versus inhibitor-stabilized: Aromatic thiols are generally supplied without polymerization inhibitors, but oxygen exclusion may be important to limit oxidative dimerization to disulfides. If a stabilizer or antioxidant is used, it will be noted on the CoA and may need removal before sensitive applications.
Recommendations for this product class:
For surface functionalization and nanomaterials work, request CoA metrics pertinent to your workflow: thiol content (iodometric or Ellman’s assay), disulfide impurity, water content (Karl Fischer), inorganic contaminants (ICP‑MS) if the surface process is metal-sensitive, and UV–vis purity if optical properties are critical.
If LC/GC methods are used downstream, confirm UV cutoff and baseline characteristics for your specific mobile phase; these are not specified here and should be verified experimentally.
Reaction and Applications
This bifunctional aryl dithiol is valuable across materials science and synthesis due to its two thiol handles and rigid, conjugated spacer.
Materials science (aligned with catalog category):
Gold and coinage-metal surface modification: Forms Au–S bonds to create self-assembled monolayers (SAMs). The para–para spacing and conjugated core provide defined intermolecular packing and tunable electronic coupling through the stilbene bridge.
Molecular electronics and plasmonics: The dithiol enables two-point attachment to electrodes/nanoparticles for single-molecule junctions and conductive linkers; the stilbene can support photoisomerization-based switching (literature-general for stilbenes).
Nanoparticle functionalization: Acts as a linker between metal surfaces and organic/inorganic phases; promotes ligand exchange on AuNPs and AgNPs.
Synthetic chemistry:
Thiol–ene and thiol–yne additions: Under radical or photochemical initiation, –SH adds across activated alkenes/alkynes to yield thioethers; bifunctionality enables crosslinking.
S‑Alkylation/S‑arylation: After base activation (ArS−), undergoes SN2 with alkyl halides or cross-coupling (e.g., C–S formation via Pd/Ni catalysis) to give bis(thioether) products.
Oxidation/reduction: Readily oxidized to disulfides; selective mono- versus di-oxidation can be controlled stoichiometrically. Disulfides may serve as reversible crosslinks in redox-responsive materials.
Metal coordination: As a dithiolate (2−), can chelate soft metals in coordination assemblies.
Practical tips (general):
Minimize oxygen exposure to limit disulfide formation; store and operate under inert gas when free thiol is required.
For SAMs, use freshly prepared, filtered solutions (0.1–1 mM) in ethanol/isopropanol and clean substrates; allow sufficient assembly time (overnight) and rinse comprehensively.
For thiol–ene coupling, select photoinitiators compatible with the chromophore and employ wavelengths avoiding strong substrate absorbance.
Reaction Conditions
The following conditions are general literature guidance for aromatic dithiols and stilbene-derived thiols; adjust to your substrates and scale. No item-specific validated protocols are provided.
S‑Alkylation (bis-thioether formation):
Base: K2CO3 or Cs2CO3 (2.2–3.0 equiv per –SH) in dry DMF; or NaH (60% dispersion) in dry THF.
Temperature/time: 0–25 °C to start; 2–16 h. Monitor by TLC/LC-MS. Typical literature yields: 60–90% depending on sterics.
Thiol–ene coupling (photochemical):
Initiation: 365–405 nm LED; photoinitiator such as DMPA (1–3 mol%) or Eosin Y with a sacrificial amine under visible light.
Solvent: MeCN, EtOAc, toluene, or DCM; degas to limit oxygen quenching.
Stoichiometry: 1.0–2.5 equiv alkene per –SH. 0.5–4 h irradiation. Often near-quantitative conversions for activated alkenes.
Disulfide formation (controlled oxidation):
Reagents: I2 (0.5 equiv per –SH pair) in MeOH/DCM with base (NaHCO3); or air/O2 bubbling with catalytic base; or H2O2 (dilute) at 0–5 °C to control over-oxidation.
Workup: Thiosulfate quench for I2; careful purification to remove elemental sulfur/iodo byproducts.
SAM formation on gold (surface assembly):
Clean Au substrates (piranha/UV-ozone; follow EHS policies). 0.1–1.0 mM thiol in absolute ethanol or isopropanol; optional N2 sparge.
Incubation: 8–24 h at rt in the dark; rinse with solvent and sonicate briefly to remove physisorbed species; dry under N2.
Deprotection (if using thioacetate precursors):
Conditions: K2CO3/MeOH or hydrazinolysis in EtOH; 0–25 °C, 0.5–2 h.
Note: The stilbene chromophore can absorb UV; avoid overlap with photoinitiation wavelengths when undesired.
Safety and Handling
Authoritative safety data should be obtained from the product’s SDS. The following are general precautions for aromatic dithiols/thiophenols and conjugated stilbene derivatives.
GHS classification (product-specific):
Signal Word: Not specified for this item; refer to SDS.
Hazard Statements, Pictograms, Classification: Not specified for this item; refer to SDS.
General hazards and characteristics (literature/chemical-class based):
Thiols often have strong, persistent odors and low odor thresholds; work in a well-ventilated fume hood.
Aryl thiols can cause skin/eye irritation and may be harmful if swallowed or inhaled.
Readily oxidizes to disulfides in air/oxygen; peroxides are not the principal concern (unlike ethers), but oxidative byproducts can form.
PPE and engineering controls:
Use chemical-resistant gloves (e.g., nitrile), lab coat, splash goggles. Handle in a fume hood.
Avoid breathing dust/particles. Use local exhaust/containment for weighing and transfers.
Storage and incompatibilities:
Store tightly closed at room temperature (per Product Data), protected from light and air to minimize oxidation. Consider storing under inert gas and including a reducing atmosphere/scavenger packet when appropriate.
Keep away from strong oxidizers (e.g., peroxides, nitric acid), strong bases (promote thiolate formation), and strong electrophiles that may alkylate the thiol.
First-aid overview (general):
Inhalation: Move to fresh air; seek medical attention if symptoms persist.
Skin/eye contact: Rinse with water for several minutes; remove contaminated clothing; obtain medical evaluation.
Ingestion: Rinse mouth; do not induce vomiting; seek medical attention.
Spill/leak response:
Contain and adsorb with inert material; avoid odor spread; dispose of according to local regulations. Decontaminate tools to remove residual odor-causing thiols.
Solvent Selection
Chemical class context: 4,4′-Dimercaptostilbene is a hydrophobic, aromatic dithiol with a conjugated stilbene spacer. It is expected to be sparingly soluble in water and soluble in common organic solvents.
Polarity/miscibility (literature-general):
Good solubility in polar aprotic solvents (DMF, DMSO, NMP) and many moderately polar organics (THF, acetone, ethyl acetate).
Soluble in nonpolar aromatics (toluene) and chlorinated solvents (DCM, CHCl3). Aqueous solubility is low.
Dielectric context: Select higher-dielectric media (DMF, DMSO) to stabilize thiolate anions for S-alkylation; choose less polar solvents (toluene, DCM) for radical thiol–ene or for Au–S self-assembly solutions where moderate polarity aids clean monolayer formation.
Acid–base considerations: For deprotonation (to aryl thiolate), use dry polar aprotics (DMF, THF) with bases (e.g., K2CO3, Cs2CO3, NaH). Avoid protic solvents that suppress nucleophilicity.
When to choose vs alternatives:
For self-assembled monolayers (SAMs) on gold: Ethanol or isopropanol is commonly used for 0.1–1 mM thiol solutions; ensure oxygen-minimized handling to limit oxidative disulfide formation.
For thiol–ene coupling: Use low-absorbing solvents for photochemistry (e.g., acetonitrile, DCM) to avoid inner-filter effects.
For S-alkylation/arylation: DMF or DMSO enable efficient base-promoted generation of the thiolate and facilitate SN2 or cross-coupling steps.
Note: Final solvent choice should be optimized based on target transformation, base/catalyst compatibility, and substrate solubility. No item-specific solvent specifications are provided.
Storage and Reconstitution
Storage conditions (from Product Data):
Store at room temperature.
Additional best practices for this chemical class (general):
Air/light sensitivity: Aromatic thiols oxidize to disulfides; minimize headspace oxygen and protect from strong light. For long-term storage, consider inert-atmosphere packaging (argon/nitrogen) and amber glass.
Container: Use tightly sealed vials with PTFE-lined caps to limit permeation and odor. Avoid reactive metals.
Stability: Avoid prolonged exposure to bases or oxidants. Check for disulfide formation by TLC/LC-MS before critical uses; reducing agents (e.g., TCEP) can regenerate thiols if needed.
Reconstitution/dissolution:
Solubility: Expect poor water solubility; readily dissolves in organic solvents such as ethanol, DMSO, DMF, THF, DCM (literature-general). Start with 1–10 mg/mL test solutions.
Stock solutions: For SAMs, prepare 0.1–1.0 mM solutions in ethanol/isopropanol immediately before use. For synthetic use, 0.05–0.5 M solutions in dry DMF/DMSO/THF are common.
Filtration: Use 0.2 µm PTFE filters to remove particulates prior to surface assembly.
Freeze–thaw guidance:
Not typically necessary at room-temperature storage, but if preparing aliquots of stock solutions, store under inert gas at 2–8 °C and avoid repeated freeze–thaw cycles to limit oxidation.
Always refer to the item’s CoA/Spec Sheet and SDS for definitive storage and handling instructions.
Structure and Identity
Brief overview: 4,4′-Dimercaptostilbene is a para–para dithiolated stilbene, featuring a conjugated trans/cis ethene linker between two thiophenyl rings, each bearing a thiol (–SH) at the para position.
SKU: D463025
Product Name: 4,4′-Dimercaptostilbene
CAS: 614756-39-7 (as provided)
CID: 19977316 (as provided)
InChIKey: 88375 (as provided; note this is a nonstandard format for InChIKey)
SMILES: Not specified for this item; refer to CoA/Spec Sheet.
Molecular Formula: Not specified for this item; refer to CoA/Spec Sheet.
• Literature/structure-based formula for 4,4′-dimercaptostilbene: C14H12S2 (informational)
Molecular Weight: Not specified for this item; refer to CoA/Spec Sheet.
• Literature/computed for C14H12S2: ~244.36 g/mol (informational)
Structural features (general, from chemical name):
Core: Stilbene (diphenylethene) with a central C=C double bond connecting two phenyl rings; E/Z isomerism possible.
Substitution: Para thiol groups on both rings (4,4′-bis(mercapto)).
Functional groups: Two aryl thiols (Ar–SH) capable of oxidation to disulfides and nucleophilic substitution after deprotonation (ArS−).
Conjugation: Extended π-system across both aryls and the ethene linker, enabling π–π stacking and photoisomerization behavior typical of stilbenes.
2D structure in words: Two benzene rings are connected by a central C=C double bond; at the para positions (relative to the ethene linkage) on each ring is an –SH substituent. This yields a symmetric, bifunctional aromatic dithiol across a rigid, conjugated spacer.
Synthetic Utility
Functional group set: Two para-position aryl thiols on a stilbene scaffold. Key reactivity arises from S–H acidity, nucleophilicity of the thiolate (ArS−), redox activity (disulfide formation/cleavage), and the photochemical responsiveness of the stilbene core.
Synthetic roles (literature-general):
Bis-thioether synthesis: Sequential or concurrent S-alkylation with alkyl halides/tosylates under basic conditions (K2CO3/Cs2CO3 in DMF; NaH in THF) yields symmetric or unsymmetric bis(thioethers). The rigid spacer benefits molecular rods/spacers.
Thiol–ene/–yne ligations: Radical or photoinitiated addition of the thiol across activated alkenes/alkynes constructs C–S bonds efficiently; bifunctionality allows crosslinking or end-functionalization at both termini of a polymer or oligomer.
Disulfide toggling: Controlled oxidation (I2, air/O2 with base, or H2O2) affords disulfides; reduction (TCEP, DTT, NaBH4) regenerates thiols — useful for redox-switchable materials.
Metal interfaces: As a dithiol, it anchors to coinage metals (Au, Ag, Cu) enabling bottom-up construction of nanoarchitectures; further orthogonal chemistry on the stilbene or appended groups broadens scope.
Cross-coupling via C–S formation: Pd- or Ni-catalyzed aryl–S bond formation from aryl electrophiles provides advanced structures; conversely, conversion to sulfenyl halides or sulfenamides expands electrophilic sulfur chemistry.
Practical considerations:
Protecting strategies (e.g., thioacetates, trityl) may be employed to control selectivity and odor; deprotection under mild conditions restores –SH.
The stilbene C=C can undergo E/Z isomerization under UV; minimize unintended photoisomerization during handling by shielding from strong UV.
Target Specificity
Not applicable. This product is a small-molecule reagent, not a biological targeting agent or antibody. No antigen/epitope, clone, isotype, or species reactivity information applies.
Utilizamos cookies para garantizar el correcto funcionamiento del sitio web y, cuando esté permitido, para mejorar su experiencia. Puede gestionar sus preferencias en cualquier momento en Configuración. Más información en nuestra Política de Cookies.
¿Quieres que te enviemos un mensaje cuando tengamos descuentos disponibles?
Recordármelo más tarde
¡Gracias! Por favor, revisa tu bandeja de entrada de correo electrónico para confirmar.
Products are supplied to verified businesses, institutions, and qualified professionals for research and development use only. Not for use in humans, animals, diagnosis, or therapy.
