3-Cyclohexylpropiolic acid - ≥97% , CAS No.4361-27-7

CAS: 4361-27-7 Cat. No.: C1360813 EC Number: 810-085-3 PubChem CID: 11378599

GRADE & PURITY ≥97%

Storage

Room temperature

Shipped In

Normal

Specifications

Specifications & Purity

≥97%

Storage

Room temperature

Shipped In

Normal

Purity

≥97%

Names and Identifiers

Canonical Smiles

C1CCC(CC1)C#CC(=O)O

IUPAC Name

3-cyclohexylprop-2-ynoic acid

InChIKey

KMRBXDYETYBRAQ-UHFFFAOYSA-N

INCHI

1S/C9H12O2/c10-9(11)7-6-8-4-2-1-3-5-8/h8H,1-5H2,(H,10,11)

Isomeric SMILES

C1CCC(CC1)C#CC(=O)O

Alternate CAS

4361-27-7

PubChem CID

11378599

Taxonomic Classification

Taxonomy Tree

• Kingdom Organic compounds
  • Superclass Organic acids and derivatives
    • Class Carboxylic acids and derivatives
      • Subclass Carboxylic acids

• Kingdom: Organic compounds
• Superclass: Organic acids and derivatives
• Class: Carboxylic acids and derivatives
• Subclass: Carboxylic acids
• Intermediate Tree Nodes: Not available
• Direct Parent: Carboxylic acids
• Alternative Parents: Monocarboxylic acids and derivatives Organic oxides Hydrocarbon derivatives Carbonyl compounds
• Molecular Framework: Aliphatic homomonocyclic compounds
• Substituents: Monocarboxylic acid or derivatives - Carboxylic acid - Organic oxygen compound - Organic oxide - Hydrocarbon derivative - Organooxygen compound - Carbonyl group - Aliphatic homomonocyclic compound
• Description: This compound belongs to the class of organic compounds known as carboxylic acids. These are compounds containing a carboxylic acid group with the formula -C(=O)OH.
• 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

Chemical and Physical Properties

• Molecular Weight: 152.190 g/mol
• XLogP3: 3.000
• Hydrogen Bond Donor Count: 1
• Hydrogen Bond Acceptor Count: 2
• Rotatable Bond Count: 0
• Exact Mass: 152.084 Da
• Monoisotopic Mass: 152.084 Da
• Topological Polar Surface Area: 37.300 Ų
• Heavy Atom Count: 11
• Formal Charge: 0
• Complexity: 200.000
• 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

Not applicable. No tested bioassay formats (e.g., WB, IHC, IF, FC) or dilution recommendations apply to this small-molecule reagent.

For synthetic applications, refer to the Reaction Conditions and Synthetic Utility sections for generalized procedural guidance.

Biological Roles

This product is a synthetic small molecule alkynoic acid and is not intended for biological administration. No endogenous biological role is associated with 3-cyclohexylpropiolic acid.

General/literature context:

• Carboxylic acids are common functional groups in metabolites, but the internal alkyne motif is rare in natural metabolism and primarily used in chemical biology as a spectroscopic handle.
• Internal alkynes provide an IR/Raman signature in the cellular “silent” region (approximately 1800–2300 cm−1), which can be exploited for label-free tracking of tagged biomolecules after derivatization (e.g., converting the acid into amides/esters with biomolecular ligands).
• Unlike terminal alkynes, internal alkynes are not suitable for classic CuAAC “click” reactions; they are more inert under bio-orthogonal conditions, which can be advantageous when a non-reactive, linear spacer is desired in probe design.

All uses are for research and laboratory development only; no clinical or in vivo claims are made or implied.

Buffer Applications

Not typically applicable. 3-Cyclohexylpropiolic acid is a hydrophobic carboxylic acid used as a synthetic building block rather than as a buffering agent.

• If pH control is needed during reactions or workup, standard laboratory buffers (e.g., phosphate, acetate) should be used separately. The compound itself is not employed to prepare analytical or biological buffers.
• For aqueous handling, form the carboxylate by adding base (e.g., NaHCO3, Na2CO3) to improve solubility; this is a reaction/workup tactic, not a buffering application.

Green Alternatives

Greener choices relate primarily to solvents and coupling reagents rather than the substrate itself.

• Solvent substitutions (general):

  • Replace DCM/CHCl3 with 2-MeTHF, CPME, or EtOAc where feasible (extractions, couplings, hydrogenations).
  • Prefer EtOH/i-PrOH for catalytic hydrogenation over nonrenewable solvents.
  • Use MeCN or 2-MeTHF instead of DMF/DMSO when coupling performance allows (easier removal, lower toxicity).

• Coupling reagent choices:

  • DMTMM or CDI are greener alternatives to HATU/HBTU/DCC, reducing urea waste and sensitizer hazards; water-compatible couplings may be possible for soluble amines.

• Workup/waste minimization:

  • Exploit acid/base partitioning to avoid silica-intensive purifications.
  • Crystallize products (esters/amides) from green solvent pairs (EtOAc/hexanes, IPA/water) when possible.

Comparison (general; literature):

• DCM vs EtOAc: Similar dissolving power for carboxylic acids; EtOAc offers better EHS profile and biodegradability.
• THF vs 2-MeTHF/CPME: Ethers of comparable performance; 2-MeTHF/CPME have better peroxide resistance and renewable sourcing (2-MeTHF from hemicellulose), though they may retain water more strongly and alter reaction rates.

Tradeoffs: Greener reagents/solvents may change reaction rates or selectivity (e.g., esterifications in EtOAc may need stronger acid or higher temperature than in toluene/DCM). Pilot small-scale trials to confirm performance.

Pharmaceutical Uses

No pharmacopeial grade or excipient status is specified for this item. It is offered for research use only.

General (non-clinical) context:

• As an intermediate: Alkynoic acids are commonly converted into amides, esters, or acid chlorides as steps in the synthesis of active pharmaceutical ingredient (API) candidates and tool compounds. The internal alkyne can serve as a linear, conformationally constrained linker affecting physicochemical properties.
• Prodrug and delivery chemistry: Conversion to alkyl/aryl esters can modulate permeability and lipophilicity for in vitro studies (research stage only).
• Spectroscopy: Internal alkynes provide an IR/Raman label in the silent region, useful for characterizing API conjugates in materials and formulation research.

No therapeutic claims are made. This material is not certified as an excipient or API; consult project-specific regulatory requirements if considering use beyond discovery research.

Physical Properties

Item-specific

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.

Computed/Literature (typical; not item-specific)

• Molecular formula: C9H12O2 (computed from structure)
• Molecular weight: ~152.19 g/mol (computed)
• Acid functionality: monoprotic carboxylic acid; pKa for related alkynoic acids typically ~2.5–3.5 (literature range; specific value for this compound not established here).
• Physical state: Small alkynoic acids with cycloalkyl substituents are often low-melting solids or high-boiling liquids; exact MP/BP for this item not specified.
• Solubility profile (qualitative, literature):
  • Miscible/soluble in common organic solvents (e.g., dichloromethane, ethyl acetate, acetonitrile, alcohols, THF).
  • Limited solubility in water at neutral pH; readily soluble in aqueous base as the carboxylate salt.
• Volatility: Expected low to moderate; carboxylic acid functionality diminishes vapor pressure versus hydrocarbons (literature expectation).
• Partitioning: The cyclohexyl group increases hydrophobicity; calculated logP for analogous cyclohexyl-alkynoic acids often ~2–3 (literature predictions; not measured for this item).
• Spectroscopic handles: Strong IR C≡C stretch in the 2100–2260 cm−1 region and C=O stretch near 1690–1725 cm−1 (literature ranges for internal alkynoic acids).

Note: Any exact numeric specifications (BP/MP, density, refractive index, UV cutoff, residuals) are not provided for this item; consult the CoA/Spec Sheet for definitive values.

Quality and Grades

Item-specific

• Grade/Purity: Not specified for this item; refer to CoA/Spec Sheet for actual assay, impurity profile, and residual solvent data.
• Stabilizers/Inhibitors: Not specified for this item.

General guidance on grades (for context)

• Research-grade alkynoic acids are typically supplied with GC/HPLC purity assays and may include water content (Karl Fischer) and residual solvent limits. If intended for spectroscopic or chromatographic applications, look for documentation noting low UV background and trace metal screening.
• Acid value/titrimetric assay can corroborate purity for carboxylic acids; NMR (1H/13C) should show the internal alkyne carbons (~70–90 ppm region for sp carbons) and a single carboxylic acid functionality.
• If ultra-low metal content is required (e.g., for catalytic studies), request trace metals analysis. For materials used in coupling chemistry, residual base/carbodiimide byproducts are typical checkpoints post-synthesis.

Please consult the Aladdin CoA/Spec Sheet for this specific SKU (C1360813) for definitive grade, purity, water, and stabilizer information.

Reaction and Applications

3-Cyclohexylpropiolic acid is a versatile alkynoic acid building block combining an internal alkyne with a carboxylic acid. It is useful across derivatization and alkyne-transforming reactions.

• Amide formation: Couples with amines using carbodiimides (DCC/EDC), uronium reagents (HATU/HBTU), or DMTMM to give alkynyl amides that retain the internal C≡C as a conformational/rigidity element or spectroscopic tag.
• Esterification: Fischer esterification (acid/alcohol, catalytic acid, heat) or Steglich esterification (DCC/DMAP) provides alkynyl esters useful as protecting groups or intermediates.
• Acid chloride activation: SOCl2 or (COCl)2 (cat. DMF) affords the acid chloride, enabling acylations of alcohols and amines under milder, often non-protic conditions.
• Hydrogenation/semihydrogenation (alkyne):
  • Lindlar catalyst (H2, Pd/CaCO3–Pb, quinoline) delivers predominantly Z-alkenoic acids.
  • Pd/C with controlled H2 can fully reduce to the saturated cyclohexylpropionic acid analog.
• Hydration/oxymercuration (alkyne): Acid- or Hg2+-catalyzed addition of water across the internal alkyne furnishes a β-keto acid, which can spontaneously decarboxylate to the corresponding methyl ketone (cyclohexyl methyl ketone derivative) under heat/acidic conditions.
• Hydroboration–oxidation (internal alkyne): Installation of carbonyls after rearrangement; conditions tuned to avoid over-oxidation of the acid.
• Radical/decarboxylative chemistry: Alkynoic acids can engage in photoredox or hypervalent iodine-mediated decarboxylation to access substituted alkynes or radicals (literature precedents).

Applications include materials and medchem intermediate synthesis where the internal alkyne imparts linear geometry, acts as a conformational spacer, or provides IR/Raman handles in the bio-orthogonal “silent” region (general/literature use, non-clinical).

Reaction Conditions

The following are general literature-style conditions for transformations of internal alkynoic acids; adjust for substrate and scale. These are not item-specific specifications.

• Amide coupling (EDC·HCl/HOBt or HATU):
  • Solvent: DCM, DMF, or MeCN (or greener 2-MeTHF).
  • Base/additives: DIPEA (2–3 equiv), catalytic DMAP (0.1 equiv) as needed.
  • Temperature: 0–25 °C; 2–16 h.
  • Typical isolated yields: 70–95% for unhindered amines (literature ranges).
• Steglich esterification (DCC/DMAP):
  • Solvent: DCM or toluene; 0–25 °C; 3–18 h.
  • Byproduct: dicyclohexylurea (filter off). Yields commonly 60–90%.
• Acid chloride formation:
  • Reagent: SOCl2 (3–5 equiv) or (COCl)2 (2–3 equiv) with a catalytic drop of DMF.
  • Conditions: reflux 0.5–2 h; remove excess under reduced pressure; use immediately.
• Semi-/hydrogenation of alkyne:
  • Lindlar (Pd/CaCO3, quinoline), 1 atm H2, EtOAc or MeOH, 20–25 °C, monitor to Z-alkenoic acid (2–8 h).
  • Full hydrogenation: Pd/C (5–10 wt%), 1–3 atm H2, EtOH or EtOAc, 20–40 °C, 2–12 h.
• Hydration to β-keto acid → decarboxylation to methyl ketone:
  • H2SO4 (aq) with catalytic HgSO4 in THF/H2O or neat aq acid; 50–80 °C; then heat to induce decarboxylation. Overall yields vary (40–80%) depending on conditions (literature).

Always run small-scale trials, monitor by TLC/LC–MS/NMR, and optimize stoichiometry and temperature for your specific substrates.

Safety and Handling

Item-specific

• GHS classification, signal word, pictograms, H-statements: Not specified for this item; refer to the SDS.
• Storage: Room temperature (per Product Data). Ship under normal conditions.

General laboratory safety (carboxylic acids; internal alkynes)

• Hazards: Carboxylic acids are typically skin/eye irritants and can cause respiratory irritation; internal alkynes are generally stable but flammable organic compounds should be handled away from ignition sources. Treat as harmful if swallowed or inhaled. Always consult the SDS for authoritative guidance.
• PPE: Lab coat, safety glasses or chemical splash goggles, and appropriate chemically resistant gloves (e.g., nitrile). Work in a fume hood to avoid inhalation of vapors or aerosols.
• Handling: Avoid breathing vapors/mist. Prevent contact with skin/eyes. Keep containers tightly closed. Ground/bond equipment if transferring flammable solutions.
• Incompatibilities: Strong bases (exothermic neutralization), strong oxidizers, strong reducing agents (which could reduce the alkyne), and reactive metals. Avoid acid chlorination reagents unless performing controlled derivatization.
• Spill/first aid (overview):
  • Skin/eyes: Rinse promptly with water for ≥15 minutes; remove contaminated clothing. Seek medical attention if irritation persists.
  • Inhalation: Move to fresh air; obtain medical advice if symptoms occur.
  • Ingestion: Rinse mouth; do not induce vomiting; seek medical attention.
• Fire: Use CO2, dry chemical, or foam. Combustion may produce CO/CO2; firefighters should wear self-contained breathing apparatus.

Always defer to the product SDS and institutional protocols for final safety requirements.

Solvent Selection

This compound is a moderately hydrophobic carboxylic acid with an internal alkyne and a cyclohexyl moiety.

• Polarity class: Amphiphilic organic acid; overall nonpolar-to-moderately polar due to cyclohexyl ring with a polar acid headgroup.
• Solubility/miscibility (literature expectations):
  • Good solubility in aprotic solvents (DCM, chloroform, THF, MTBE, CPME) and polar organics (MeOH, EtOH, AcOH, MeCN, DMF, DMSO).
  • Limited solubility in water at neutral pH; highly soluble in aqueous base as the carboxylate salt (pH > pKa).
• Typical use scenarios:
  • Coupling chemistry (amide/ester formation): DMF, DCM, THF, or MeCN are commonly selected; 2-MeTHF or EtOAc provide greener options.
  • Hydrogenation or semi-hydrogenation: EtOH, EtOAc, or green ethers (2-MeTHF/CPME) are practical media with Pd or Lindlar catalysts.
  • Acid chloride formation: Anhydrous chlorinated solvents (DCM) or neat SOCl2/oxalyl chloride with catalytic DMF.
• Practical tips:
  • For aqueous workups, adjust pH to switch between acid (extract into organics) and carboxylate (partition into water). Acidify to pH ~1–2 to re-extract the free acid (general practice).
  • If crystallization is desired, test solvent pairs such as EtOAc/hexanes or toluene/hexanes.

Small comparison (general):

• DCM: excellent dissolving power; volatile but non-green. EtOAc/2-MeTHF: greener, good for extractions and many couplings. MeOH/EtOH: useful for esterifications and catalytic hydrogenations.

Storage and Reconstitution

Item-specific

• Storage temperature: Room temperature (per Product Data).
• Shipping: Normal conditions.

General guidance (small organic acids)

• Store tightly closed in a dry, well-ventilated place. Protect from prolonged exposure to moisture; although stable, the free acid can absorb moisture and trace bases.
• If transferring to working containers, consider inert gas backfill (N2/Ar) to minimize oxidative or moisture-related degradation of sensitive derivatives; the parent internal alkyne is typically stable.
• No reconstitution is required. If preparing stock solutions:
  • Organic stocks: Dissolve in DCM, MeCN, MeOH, EtOH, THF, DMF, or DMSO as appropriate; prepare fresh for sensitive transformations.
  • Aqueous handling: Convert to the carboxylate with base (e.g., NaOH/NaHCO3) for temporary solubilization; neutralize to recover the free acid.
• Freeze–thaw: Not applicable to the neat solid/liquid. For solutions, store at 2–8 °C or −20 °C as needed and avoid repeated freeze–thaw cycles to prevent concentration drift.

Always refer to the SDS and the item’s CoA/Spec Sheet for any additional, product-specific storage notes.

Structure and Identity

Item-specific (from Product Data)

• Product name: 3-Cyclohexylpropiolic acid
• CAS: 4361-27-7
• CID: 11378599
• InChIKey: 184128 (as provided)
• Storage conditions: Room temperature
• Shipped: Normal

Computed/Literature (structure description; not item-specific specs)

• Preferred IUPAC-style name (literature): 3-cyclohexylprop-2-ynoic acid; equivalently cyclohexyl–C≡C–CO2H
• Molecular formula (computed): C9H12O2
• Molecular weight (computed): ~152.19 g/mol
• SMILES (representative, literature): O=C(O)C#CC1CCCCC1
• InChI (representative, literature): InChI=1S/C9H12O2/c10-9(11)6-5-8-3-1-2-4-7-8/h5-6,8H,1-4,7H2,(H,10,11)

Structural features (general)

• Functional groups: carboxylic acid (–CO2H); internal alkyne (–C≡C–) directly alpha to the acid carbonyl.
• Ring system: saturated cyclohexyl substituent attached to the β-carbon of the alkyne.
• 2D description: a cyclohexyl ring is bonded to one carbon of an sp-hybridized C≡C unit; the adjacent sp-carbon is bonded to a carbonyl carbon of a carboxylic acid. No stereogenic centers; linear C≡C segment connects a bulky cyclohexyl group to the acid moiety.

Synthetic Utility

Key reactivity of 3-cyclohexylpropiolic acid arises from the combination of a carboxylic acid and an internal alkyne.

• Carboxyl activation:
  • Acid chlorides via SOCl2 or oxalyl chloride (cat. DMF), enabling acylation of alcohols (esters) and amines (amides).
  • Carbodiimide-mediated coupling (DCC/EDC) with DMAP or HOBt/HOAt additives; greener alternatives include DMTMM or CDI for urea-free protocols.
  • Steglich esterification for base/heat-sensitive alcohol partners.
• Alkyne transformations:
  • Catalytic hydrogenation to Z-alkenoic acids (Lindlar) or full saturation (Pd/C) to alkylpropionic acid derivatives.
  • Electrophilic hydration (H2SO4/HgSO4 or Au-catalysis) to β-keto acids; facile decarboxylation yields the corresponding methyl ketone (cyclohexyl methyl ketone derivative).
  • Metal-catalyzed additions (e.g., hydroboration of internal alkynes) followed by oxidation to carbonyls, with care to preserve the acid group.
• Strategic roles:
  • Linear, rigid spacer in amide/ester-linked libraries (e.g., medchem SAR).
  • Precursor to diversified scaffolds via selective modification of either the acid or alkyne, enabling orthogonal synthesis routes.

Workup/Isolation Tips:

• Phase switching by pH allows efficient separations. After coupling, extract basic impurities into aqueous acid; recover product into organics at low pH.
• For acid chlorides, exclude moisture and vent appropriately; quench residual reagents carefully (ice–aqueous NaHCO3).

Target Specificity

Not applicable. This product is a small-molecule reagent, not a biological macromolecule or affinity reagent. No antigen/epitope or species reactivity data are relevant.

Frequently Asked Questions

What is the purity of this product?

This product is supplied at ≥97% purity (chemical assay). Lot-specific values are stated on the Certificate of Analysis.

How should this product be stored?

Store at room temperature.

How is this product shipped?

This product ships under standard ambient conditions. No temperature-controlled packaging is required.

What are the CAS number, molecular formula and molecular weight?

The CAS Number is 4361-27-7. InChIKey KMRBXDYETYBRAQ-UHFFFAOYSA-N.

What documentation is provided?

Available product documentation, including Certificates of Analysis (COA), Safety Data Sheets (SDS), and specification sheets, is shown in the product document area. Document availability and access follow the current site policy.