6-Ethylpyridine-3-boronic acid - ≥95% , CAS No.1001907-69-2

CAS: 1001907-69-2 Cat. No.: E734699 Formula: C₇H₁₀BNO₂ Molecular Weight: 150.97 PubChem CID: 68104586

GRADE & PURITY ≥95%

Storage

Room temperature

Specifications

Specifications & Purity

≥95%

Storage

Room temperature

Purity

≥95%

Names and Identifiers

Canonical Smiles

B(C1=CN=C(C=C1)CC)(O)O

IUPAC Name

(6-ethylpyridin-3-yl)boronic acid

InChIKey

LPXSVMTZVQACFE-UHFFFAOYSA-N

INCHI

1S/C7H10BNO2/c1-2-7-4-3-6(5-9-7)8(10)11/h3-5,10-11H,2H2,1H3

Isomeric SMILES

B(C1=CN=C(C=C1)CC)(O)O

PubChem CID

68104586

Molecular Weight

150.97

Taxonomic Classification

Taxonomy Tree

• Kingdom Organic compounds
  • Superclass Organoheterocyclic compounds
    • Class Pyridines and derivatives

• Kingdom: Organic compounds
• Superclass: Organoheterocyclic compounds
• Class: Pyridines and derivatives
• Subclass: Not available
• Intermediate Tree Nodes: Not available
• Direct Parent: Pyridines and derivatives
• Alternative Parents: Heteroaromatic compounds Boronic acids Organic metalloid salts Azacyclic compounds Organopnictogen compounds Organonitrogen compounds Organoboron compounds Organic oxygen compounds Hydrocarbon derivatives
• Molecular Framework: Aromatic heteromonocyclic compounds
• Substituents: Pyridine - Heteroaromatic compound - Boronic acid - Boronic acid derivative - Azacycle - Organic metalloid salt - Organic nitrogen compound - Organic oxygen compound - Organopnictogen compound - Hydrocarbon derivative - Organic salt - Organonitrogen compound - Organoboron compound - Aromatic heteromonocyclic compound
• Description: This compound belongs to the class of organic compounds known as pyridines and derivatives. These are compounds containing a pyridine ring, which is a six-member aromatic heterocycle which consists of one nitrogen atom and five carbon atoms.
• 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: 150.970 g/mol
• Hydrogen Bond Donor Count: 2
• Hydrogen Bond Acceptor Count: 3
• Rotatable Bond Count: 2
• Exact Mass: 151.08 Da
• Monoisotopic Mass: 151.08 Da
• Topological Polar Surface Area: 53.400 Ų
• Heavy Atom Count: 11
• Formal Charge: 0
• Complexity: 121.000
• 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

XLogP3

Application Protocols

No item-specific, validated biological assay protocols are provided for this small-molecule reagent. For synthetic applications, consider the following general workflows (literature; not product specifications):

• Suzuki–Miyaura coupling setup: Charge aryl halide, base, solvent mixture (e.g., dioxane/H2O), and Pd catalyst to a dry vessel under inert gas. Add 6-ethylpyridine-3-boronic acid (1.2–1.5 equiv). Heat (e.g., 80 °C) until completion by TLC/LC-MS. Work up and purify by chromatography.
• Chan–Lam coupling: Combine boronic acid, nucleophile (amine/alcohol), Cu(OAc)2 (5–10 mol%), and MeOH or MeCN under air at rt–40 °C; stir until conversion.

For detailed, stepwise protocols tailored to your substrates, consult peer-reviewed procedures and optimize catalyst/ligand/base for the specific electrophile and heteroaryl system.

Biological Roles

Item-specific biological data: Not specified for this item; refer to literature and SDS. This product is supplied for research use only.

General/literature context:

• Boronic acids form reversible covalent complexes with cis-diols (e.g., in carbohydrates), a property exploited in sensor design, affinity materials, and separations. Heteroaryl boronic acids can tune binding affinity and pKa near physiological conditions.
• The pyridine nitrogen confers basicity and can participate in hydrogen bonding and metal coordination, useful in designing ligands, probes, and metal–organic frameworks.
• In medicinal chemistry, substituted pyridines are common heteroaromatic pharmacophores; boronic acids serve as synthetic linchpins to access such structures rather than acting as bioactive species themselves.

No claims are made regarding physiological activity or therapeutic use of this specific compound. Any biological experiments should be conducted under appropriate laboratory approvals and conditions.

Buffer Applications

This compound is not used as a buffering agent. Boronic acids and pyridines do not provide defined buffering ranges suitable for common biochemical buffers. If your work involves interactions with saccharides or diols, note that boronic acids can bind diols in aqueous buffers (typically at pH above their boronic acid pKa), but the compound itself is not a buffer.

For buffer preparation in related workflows, consider standard systems such as phosphate (pH 6–8), Tris (pH 7–9), or MOPS (pH 6.5–7.9), selected to match your assay requirements.

Green Alternatives

Greener strategies relate primarily to solvent and reagent choices, since the core transformation (Suzuki/Chan–Lam) is well established.

Potential improvements (literature/guidance):

• Solvents: replace dioxane/DMF with greener choices such as water/ethanol, 2-MeTHF, CPME, or MeCN/water mixtures when compatible with the catalyst system.
• Bases: prefer carbonate/phosphate bases over strong hydroxides to minimize byproducts and improve safety.
• Catalysis: employ highly active Pd systems at low loadings, or heterogeneous Pd/C under flow to aid recovery. Copper-free protocols where feasible.

Comparison (general; not item-specific):

• Dioxane vs 2-MeTHF: 2-MeTHF has a better environmental profile (biorenewable origins, favorable EHS) and often mimics THF/dioxane in coupling performance.
• DMF/NMP vs MeOH/H2O: MeOH/H2O is less hazardous and often adequate for many Suzuki couplings with appropriate ligands.
• Aryl boronic acid vs pinacol boronate ester: esters can be more stable (less protodeboronation), enabling milder, aqueous/green conditions with reduced waste.

Trade-offs:

• Water-rich media may reduce solubility of hydrophobic partners; phase management or surfactants/micellar catalysis can help.
• Some green solvents require re-optimization of ligand/base to maintain rates and selectivity.

Pharmaceutical Uses

Item-specific pharmacopeial status or excipient use: Not specified for this item; refer to CoA/Spec Sheet. This product is for research use only.

General context in pharmaceutical R&D (literature):

• Role: heteroaryl boronic acids are synthetic building blocks for assembling drug-like pyridyl motifs. The boronic acid itself is typically an intermediate and not part of the final formulation.
• Applications: structure–activity relationship (SAR) exploration via rapid installation of the 3-pyridyl unit onto diverse aryl/vinyl halides using Suzuki–Miyaura coupling.
• Considerations: for GMP or clinical manufacturing, supply chain control, impurity profiles (including residual metals, boroxines), and robust analytical ID (qNMR, HPLC, HRMS) are required.

No therapeutic claims are made for this compound. It is not sold for human or veterinary use.

Physical Properties

Item-specific physicochemical specifications (melting point, water content, residual metals, UV cutoff, etc.): Not specified for this item; refer to CoA/Spec Sheet.

General/literature expectations for heteroaryl boronic acids (for planning only; not product specifications):

• Physical state: typically crystalline solids; many pyridyl boronic acids are off‑white solids.
• Acid–base behavior:
  • Boronic acid pKa (B(OH)2 ⇌ B(OH)O− + H+): often ~8–9 (literature, varies with ring substitution and heteroatoms).
  • Pyridine ring basicity: conjugate acid pKa typically ~5–6 for unsubstituted pyridines; a 6‑ethyl group is weakly electron donating, while a 3‑boronic acid is mildly withdrawing; net effect modest (qualitative).
• Solubility profile (qualitative):
  • Moderately soluble in polar aprotic organics (DMSO, DMF, acetonitrile) and alcohols; limited solubility in nonpolar hydrocarbons; increased aqueous solubility under basic conditions via boronate formation.
• Thermal behavior: many aryl/heteroaryl boronic acids melt/decompose in the 80–250 °C range; some can dehydrate to boroxines upon heating/drying (literature).
• Hygroscopicity: low-to-moderate; can form hydrogen-bonded networks; boroxine formation is reversible with moisture.

For exact values for this lot (mp, assay, impurity profile, residual solvents/metals), consult the CoA/Spec Sheet.

Quality & Grades

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

Guidance on typical grades for boronic acid building blocks (general information):

• Research/technical grade: suitable for routine synthetic use; assay typically >95% with trace organic/elemental impurities controlled to practical levels for cross-coupling.
• High-purity/HPLC grade: tighter control of organic impurities and UV-absorbing contaminants; beneficial for sensitive medicinal chemistry or analytical workflows.
• Trace metal specifications: for cross-coupling, residual Pd, Ni, Cu from manufacturing are sometimes reported; if critical, request ICP-MS data.

Stabilizer implications: Boronic acids are generally provided neat without stabilizers. Some vendors offer pinacol boronate esters or MIDA boronates for enhanced stability/handling—these are different materials with distinct specifications.

What to check on the CoA for this item:

• Assay/purity method (qNMR, HPLC, GC)
• Identity confirmation (1H/13C NMR, HRMS)
• Water content (Karl Fischer) and evidence of boroxine content if relevant
• Residual solvents and heavy metals (if applicable)

For regulated applications (e.g., GMP intermediates), request supporting documentation and batch-specific analytical data.

Reaction & Applications

Primary application: as a heteroaryl boronic acid, this reagent is designed for C–C bond formation via palladium-catalyzed cross-coupling.

Key reaction families (literature):

• Suzuki–Miyaura coupling with aryl/vinyl halides or pseudohalides (Ar–X, X = I, Br, Cl, OTf).
  • Mechanistic note: transmetalation of the boronate to Pd(II) is base-assisted; heteroaryl systems can coordinate Pd, so ligand choice is important to suppress off-cycle binding.
• Chan–Lam coupling (Cu-mediated) with N- or O-nucleophiles to give C–N/C–O bonds, typically under aerobic conditions at ambient temperature.
• One-pot or in situ transformations: protodeboronation (to 6-ethylpyridine) is a possible side pathway at elevated temperature/strong base; mitigated by milder bases and optimized ligands.

Practical tips:

• Base selection: K2CO3, Cs2CO3, Na2CO3, K3PO4, or aqueous NaOH; for heteroaryl boronic acids, milder bases and lower temperatures often reduce protodeboronation.
• Solvent systems: dioxane/H2O, THF/H2O, MeOH/H2O, or MeCN/H2O are common; ensure adequate dissolution/phase mixing.
• Catalyst/ligands: Pd(PPh3)4, Pd2(dba)3 with dialkylbiaryl phosphines (e.g., SPhos, XPhos), or Buchwald precatalysts. For aryl chlorides, employ more active ligands.
• Handling: avoid prolonged heating in strongly basic aqueous media; consider using the corresponding pinacol boronate ester if instability is observed, then hydrolyze in situ.

Use cases:

• Assembly of ethyl-substituted pyridyl motifs in agrochemical and medicinal chemistry programs.
• Late-stage diversification of heteroaromatic scaffolds via C–C and C–N/O couplings.

Reaction Conditions

General literature guidance for couplings of pyridyl boronic acids (optimize per substrate):

Suzuki–Miyaura coupling

• Representative conditions:
  • Electrophile: aryl/vinyl bromide or chloride (1.0 equiv)
  • 6-Ethylpyridine-3-boronic acid: 1.2–1.5 equiv
  • Catalyst: 1–3 mol% Pd(PPh3)4 or 0.5–2 mol% Pd2(dba)3 + 1–4 mol% SPhos/XPhos; for aryl chlorides use more active ligands (e.g., RuPhos, tBu-XPhos)
  • Base: 2–3 equiv K2CO3, Cs2CO3, K3PO4, or Na2CO3 in H2O
  • Solvent: dioxane/H2O (3:1), THF/H2O, MeOH/H2O, or MeCN/H2O
  • Temperature/time: 50–100 °C, 2–16 h
• Notes: Maintain moderate basicity to limit protodeboronation; degas solvents; consider microwave heating for rate enhancement.

Chan–Lam coupling (C–N/C–O)

• Conditions:
  • Copper(II) acetate or copper salts (5–20 mol%), pyridine base or amine partner as ligand
  • Solvent: MeOH, MeCN, DCM/MeOH, or toluene/MeOH mixtures
  • Ambient temperature to 40 °C; air or O2 as terminal oxidant
  • Time: 6–24 h

Workup/purification:

• Quench with water; extract with suitable organic solvent; remove catalyst residues by silica, scavengers, or activated carbon. Monitor potential boroxine impurities; aqueous base washes can revert boroxines to boronic acids for cleaner chromatography.

Safety & Handling

Hazard classification for this specific item:

• 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 guidance for heteroaryl boronic acids (literature/good practice):

• Expected hazards: typically low-to-moderate acute toxicity; may cause irritation to skin, eyes, and respiratory tract. Avoid dust generation and inhalation.
• PPE: lab coat, safety glasses or goggles, and appropriate gloves (e.g., nitrile). Use in a chemical fume hood to minimize dust exposure.
• Incompatibilities: strong oxidizers; strong bases/acids can alter speciation (boronate/boroxine formation). Avoid prolonged heating that can drive dehydration to boroxines.
• First aid (general):
  • Inhalation: move to fresh air; seek medical attention if symptoms persist.
  • Skin/Eye contact: rinse with water for at least 15 minutes; remove contaminated clothing; seek medical advice if irritation continues.
  • Ingestion: rinse mouth; do not induce vomiting; seek medical attention.
• Spill response: avoid dust; collect mechanically or dampen and absorb; place in appropriate container for disposal according to local regulations.

Storage per product data: store at room temperature. Keep container tightly closed, dry, and protected from excessive heat and moisture. Always defer to the product SDS for authoritative safety information.

Solvent Selection

As a heteroaryl boronic acid, 6-ethylpyridine-3-boronic acid exhibits moderate polarity and hydrogen-bonding capability via –B(OH)2.

General solvent behavior (literature/guidance):

• Polar aprotic solvents: DMSO, DMF, NMP, and acetonitrile typically dissolve well and are preferred for stock solutions and high-throughput screening of coupling conditions.
• Alcohols: methanol, ethanol, i-PrOH dissolve many boronic acids; useful as co-solvents in Suzuki couplings and in purification.
• Aqueous media: solubility increases under basic conditions (formation of boronate anion). Aqueous-organic mixtures are routine for cross-coupling.
• Nonpolar: poor solubility in hexanes/toluene alone; often needs a polar co-solvent or phase-transfer conditions.

Selection tips for applications:

• Suzuki–Miyaura coupling: dioxane/H2O, THF/H2O, MeOH/H2O, or MeCN/H2O are common. Choice depends on base, aryl halide, and catalyst system.
• Handling solutions: prepare fresh solutions to limit slow dehydration or speciation changes; store cold and basic if prolonged storage is required.

Small comparison (general):

• Dioxane/H2O: balances substrate solubility and catalyst stability; good for heteroaryl systems.
• MeOH/H2O: greener, inexpensive; may require ligand/catalyst compatible with protic media.
• MeCN/H2O: good for higher polarity substrates; facilitates workup by evaporation.

Confirm compatibility with your specific catalyst/base system before scale-up.

Storage & Reconstitution

Storage conditions (item-specific):

• Store at room temperature (per product data). Keep container tightly closed in a dry, well-ventilated place. Protect from excessive moisture and heat to minimize dehydration to boroxines.

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

Reconstitution and handling (general guidance):

• Solubility: readily prepared as stock solutions in DMSO, DMF, MeOH, EtOH, or MeCN. For aqueous applications, dissolve in minimal organic solvent, then dilute with water/base as needed.
• Stock solutions: prepare fresh when possible. If storing solutions, keep under inert gas at 2–8 °C and avoid prolonged storage in strongly basic media.
• Solid handling: minimize exposure to humid air; if partial dehydration occurs, dissolution in aqueous base can re-form the boronic acid from boroxines.

Shelf life: Not specified for this item; check the CoA for retest/expiry dates.

Research use only: Not for human or veterinary use.

Structure & Identity

6-Ethylpyridine-3-boronic acid is a heteroaryl boronic acid featuring a pyridine ring bearing an ethyl substituent at the 6-position and a boronic acid group at the 3-position.

• Item-specific identifiers:
  • CAS: 1001907-69-2
  • SKU: E734699
  • InChIKey: Not specified for this item; refer to CoA/Spec Sheet. (Value provided in product data appears incomplete.)
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.
• Structure description (general):
  • Core: a six-membered aromatic pyridine (one ring nitrogen).
  • Substituents: an ethyl group at C-6 (ortho to the ring nitrogen), and a boronic acid moiety [–B(OH)2] at C-3.
  • Functional groups: heteroaromatic ring (pyridine), boronic acid (Lewis acidic boron center, two hydroxyls), ethyl substituent (weakly electron-donating/inductive).
  • Stereochemistry: none (achiral).
• Computed/literature identifiers (general guidance, not item-specific specs):
  • Empirical formula (computed from structure): C7H10BNO2
  • Formula weight (computed): ~151.0 g/mol

Notes: Structural descriptors like SMILES and a verified InChIKey should be confirmed on the product CoA/Spec Sheet for this specific item.

Synthetic Utility

Functional group set and reactivity:

• Boronic acid [–B(OH)2]: engages in Pd-catalyzed Suzuki–Miyaura coupling (Csp2–Csp2), oxidative Cu-mediated Chan–Lam couplings (C–N/O), and can be masked/unmasked via boronate esters (pinacol, MIDA) for multistep sequences.
• Pyridine ring: heteroatom can coordinate catalysts and metals, modulating reactivity; regiochemistry (3-boryl, 6-ethyl) offers specific vectors in scaffold design.

Retrosynthetic value:

• Serves as the nucleophilic cross-coupling partner to introduce a 6-ethyl-3-pyridyl fragment onto aryl/vinyl electrophiles. Particularly attractive where direct C–H activation at the target is infeasible.

Transformations (literature examples):

• Suzuki coupling to build biaryls and styryl-pyridines (aryl/vinyl bromides/chlorides; ligands like SPhos/XPhos for deactivated chlorides).
• Chan–Lam amination/etherification to give 3-(amino/alkoxy)pyridyl derivatives under mild, aerobic conditions.
• Conversion to trifluoroborate salts (K[BF3]) for enhanced stability and handling in coupling.
• Protodeboronation (as a controlled step or side reaction) to access 6-ethylpyridine under specific conditions.

Practical notes:

• Heteroaryl boronic acids may show lower stability vs phenyl analogs; consider using the corresponding pinacol boronate ester if prolonged storage or high-temperature steps are required.

Target Specificity

Not applicable. This product is a small-molecule synthetic reagent (heteroaryl boronic acid) and does not possess antibody/biological target specificity. No antigen, clone, isotype, or species reactivity information applies.

Frequently Asked Questions

What is the purity of this product?

This product is supplied at ≥95% purity (chemical assay). Lot-specific values are stated on the Certificate of Analysis.

How should this product be stored?

Store at room temperature.

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

The CAS Number is 1001907-69-2, the molecular formula is C7H10BNO2, and the molecular weight is 150.97 g/mol. InChIKey LPXSVMTZVQACFE-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.