What Is 2-Chloro-3-ethoxyphenylboronic Acid?

2-Chloro-3-ethoxyphenylboronic acid (SKU: C180617) is an arylboronic acid in which the phenyl ring carries a chloro substituent at the 2-position and an ethoxy substituent at the 3-position, in addition to the boronic acid group (–B(OH)₂) at the 1-position. This combination of electron-withdrawing (Cl) and electron-donating (OEt) groups on the same ring creates a nuanced electronic environment that can be exploited in selective cross-coupling chemistry and in the design of pharmacologically active molecules.

Arylboronic acids of this type are stable, bench-top-accessible solids that act as mild Lewis acids. They are widely used as coupling partners in transition-metal-catalyzed reactions due to the ease with which the boron center undergoes transmetalation.

Key Applications in Synthetic Chemistry

Suzuki–Miyaura Cross-Coupling: The most prominent use of 2-Chloro-3-ethoxyphenylboronic acid is as a boronic acid partner in palladium-catalyzed Suzuki–Miyaura reactions. In this reaction, the arylboronic acid couples with aryl or vinyl halides (or triflates) in the presence of a Pd catalyst and a base to form biaryl or styryl products. The chloro group on the ring can itself serve as a handle for further functionalization, enabling sequential coupling strategies.

Medicinal Chemistry Building Block: The simultaneous presence of halogen, ether, and boronic acid functionalities makes this compound useful for the construction of complex scaffolds encountered in drug discovery programs, particularly where multi-step convergent synthesis is required.

Materials Science: Functionalized arylboronic acids are explored as monomers or intermediates in the synthesis of conjugated polymers and organic semiconductors, although specific literature for this exact compound should be confirmed before application.

Storage, Stability, and Handling

Storage: Boronic acids can undergo slow protodeboronation or oxidation upon prolonged exposure to moisture, air, and elevated temperatures. It is recommended to store 2-Chloro-3-ethoxyphenylboronic acid in a tightly sealed container in a cool, dry environment, away from direct light. Where long-term stability is critical, storage under an inert atmosphere (nitrogen or argon) is advisable. Refer to the product certificate of analysis (CoA) and Safety Data Sheet (SDS) for lot-specific storage conditions.

Handling: Follow standard laboratory safety protocols. Wear appropriate personal protective equipment (gloves, lab coat, eye protection). Avoid generating dust and prolonged inhalation. In case of skin or eye contact, rinse immediately with copious water and seek medical advice if irritation persists.

Stability Considerations: The ethoxy group provides additional steric protection compared to unsubstituted phenylboronic acids. Nevertheless, boronic acids in general are susceptible to hydrolysis under strongly acidic or basic aqueous conditions, which should be considered when designing reaction workup procedures.

Reaction Setup and Practical Tips

Typical Suzuki Coupling Conditions: A standard Suzuki–Miyaura protocol employs 1.0–2.0 equivalents of the boronic acid relative to the electrophilic coupling partner, a palladium catalyst (e.g., Pd(PPh₃)₄, Pd(dppf)Cl₂, or Pd(OAc)₂ with a phosphine ligand), an inorganic base (e.g., K₂CO₃, Cs₂CO₃, or Na₂CO₃), and a mixed aqueous–organic solvent system (e.g., DMF/H₂O, THF/H₂O, or dioxane/H₂O). Reactions are typically conducted under an inert atmosphere at temperatures ranging from room temperature to 100 °C depending on the electrophile reactivity.

The Chloro Substituent as a Secondary Handle: Because the chloro group on the ring is itself an aryl chloride, it can participate in further Pd-catalyzed cross-coupling under appropriate conditions. Researchers should plan reaction sequences carefully if selective mono-coupling is desired.

Solubility: Arylboronic acids are generally soluble in polar organic solvents such as THF, DMF, DMSO, and ethanol. Slight heating may be required to achieve complete dissolution. Specific solubility data for C180617 should be verified from the product CoA.

Ordering and Quality Information

2-Chloro-3-ethoxyphenylboronic acid is available from Aladdin Scientific under SKU C180617. Each lot is accompanied by a Certificate of Analysis (CoA) documenting purity and identity confirmation. Researchers are encouraged to review the CoA and SDS prior to use.

For bulk quantities, custom synthesis inquiries, or technical support regarding reaction optimization, please contact Aladdin Scientific's customer service team. Procurement teams can reference SKU C180617 when placing orders to ensure accurate fulfillment.

Aladdin Scientific is committed to supplying high-quality research reagents with rigorous quality control to support reproducible science. For the most up-to-date pricing, availability, and regulatory documentation, please visit the product page on the Aladdin Scientific website or contact your regional representative.