4-Bromo-2-hydroxy-5-methylbenzaldehyde - ≥95% , CAS No.1427373-22-5

CAS: 1427373-22-5 Cat. No.: B980833 PubChem CID: 130063132

GRADE & PURITY ≥95%

Storage

Room temperature

Specifications

Spezifikationen & Reinheit

≥95%

Storage

Room temperature

Reinheit

≥95%

Namen und Kennungen

Kanonisches Lächeln

CC1=CC(=C(C=C1Br)O)C=O

IUPAC Name

4-bromo-2-hydroxy-5-methylbenzaldehyde

InChIKey

JFXHVNHTPWAUKF-UHFFFAOYSA-N

INCHI

1S/C8H7BrO2/c1-5-2-6(4-10)8(11)3-7(5)9/h2-4,11H,1H3

PubChem CID

130063132

Chemische und physikalische Eigenschaften

• Molekulargewicht: 215.040 g/mol
• XLogP3: 2.600
• Hydrogen Bond Donor Count: 1
• Hydrogen Bond Acceptor Count: 2
• Rotatable Bond Count: 1
• Exact Mass: 213.963 Da
• Monoisotopic Mass: 213.963 Da
• Topological Polar Surface Area: 37.300 Ų
• Heavy Atom Count: 11
• Formal Charge: 0
• Complexity: 149.000
• 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 validated bioassay or immunoassay protocols are associated with this small-molecule reagent. For synthetic applications, see the Reaction Conditions and Synthetic Utility sections for general procedural guidance.

Biological Roles

This compound is a synthetic aromatic building block and does not have established endogenous biological roles.

General considerations (literature)

• Phenolic salicylaldehyde scaffolds are widely used to prepare Schiff bases that function as metal chelators and enzyme model ligands; such ligands can modulate metal-centered reactivity in bioinspired catalysis studies.
• The o-hydroxy–aldehyde motif may engage in excited-state intramolecular proton transfer (ESIPT) when derivatized, enabling fluorescent probe development; any biological imaging applications derive from the designed conjugates rather than this starting material itself.
• Brominated aromatics are typically hydrophobic and may show nonspecific membrane interactions; however, no specific biological targets are associated with this compound.

Compliance

• Research Use Only: This product is intended strictly for laboratory research. It is not for diagnostic, therapeutic, or clinical use.

Buffer Applications

Not typically applicable. 4-Bromo-2-hydroxy-5-methylbenzaldehyde is a hydrophobic aromatic aldehyde and is not used as a buffering agent. For aqueous work, prepare stock solutions in a compatible organic cosolvent (e.g., DMSO, ethanol) and dilute into assay buffers as needed, ensuring final cosolvent levels are compatible with the system.

Green Alternatives

Although this product is a solid building block rather than a solvent, greener choices relate to the reaction media and methods used with it.

Greener solvent and method options (general)

• Replace DMF/NMP with 2-MeTHF, Cyrene, propylene carbonate, or ethanol/water mixtures where compatible.
• Employ aqueous-micellar catalysis for cross-couplings (e.g., TPGS-750-M, Savie) to reduce organic solvent usage.
• For imine formation, use ethanol or 2-MeTHF with Dean–Stark or molecular sieves instead of chlorinated solvents.
• Choose Pd catalysis with ligand systems effective in water/green solvents; consider nickel catalysis for certain couplings to reduce precious metal use.

Illustrative comparison (general)

• DMF vs 2-MeTHF: DMF offers high polarity but problematic EHS and workup; 2-MeTHF is bio-based, lower toxicity, easy separation, but may require longer times or higher temperatures.
• DCM vs EtOAc: DCM has high volatility and toxicity; EtOAc is biodegradable and widely accepted, though solubility may be lower.

Waste minimization

• Protect/deprotect strategically to avoid extra steps (e.g., transient in situ silylation of phenol).
• Use catalytic dehydrating methods for imine formation to avoid stoichiometric reagents.

Note: Selection must balance EHS with reaction performance; validate on small scale.

Pharmaceutical Uses

This product is not an excipient and has no pharmacopeial monograph noted here. It may serve as a synthetic intermediate in the preparation of drug-like candidates or ligands during medicinal chemistry campaigns, especially where an o-hydroxybenzaldehyde core and/or an aryl bromide handle are desired for diversification.

Formulation/processing notes (general)

• For in vitro screening, prepare solutions in DMSO or ethanol before dilution into assay media; confirm stability of the aldehyde against hydration/oxidation.
• Avoid amine-containing excipients or basic media if aldehyde integrity must be preserved; consider forming protected derivatives (acetals/oximes) for storage if required.

No therapeutic claims are made. Research use only.

Physical Properties

Item-specific specifications

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Grade/Purity: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular formula (item): Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight (item): Not specified for this item; refer to CoA/Spec Sheet.

Literature/general values for this structure (reference only; not product specifications)

• Approx. molecular formula: C8H7BrO2
• Approx. molecular weight: ~215.04 g/mol
• Structural class: substituted salicylaldehyde (aryl aldehyde, phenol, aryl bromide)
• Intramolecular interactions: often exhibits a six-membered intramolecular H-bond between the 2–OH and the aldehyde oxygen, which can lower solution polarity and shift IR/1H NMR signals (e.g., downfield phenolic OH).

Practical solubility guidance (general)

• Aryl aldehydes of this type are typically soluble in polar aprotic organic solvents (e.g., DMSO, DMF, acetone, acetonitrile) and moderately soluble in alcohols and chlorinated solvents; very low solubility in water. Exact solubility for this item is not specified; confirm experimentally.

Other properties

• Partitioning: bromine and methyl substituents increase hydrophobicity relative to salicylaldehyde (qualitative).
• UV behavior: aromatic chromophore and formyl group provide strong UV absorption; for quantitative values and cutoffs, Not specified for this item; refer to CoA/Spec Sheet.

Quality and Grades

Item-specific quality information

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

Guidance on grade meaning and selection (general)

• Research grade: Suitable for most synthetic, screening, and materials applications. For sensitive catalysis or analytical applications, users may require additional purification or specify tighter impurity limits (e.g., water, peroxides, metals)—these are Not specified for this item; refer to CoA/Spec Sheet.
• HPLC/UV grade (if applicable): Emphasizes low background absorbance; for aromatic aldehydes, residual UV-active impurities can affect chromatographic baselines. This item’s UV cutoffs/absorbance are Not specified for this item; refer to CoA/Spec Sheet.

Impurities and practical notes (general for aryl aldehydes)

• Typical impurities: corresponding carboxylic acid (air-oxidation), unreacted phenols, brominated isomers, residual halides/solvents.
• Verification: Confirm identity by 1H NMR (characteristic aldehyde singlet ~9.5–10.5 ppm; phenolic OH often downfield with H-bond), 13C NMR (formyl ~190–200 ppm), HRMS, and HPLC/GC purity as needed.
• Drying: If moisture-sensitive application is planned (e.g., imine formation), dry under vacuum and handle under inert atmosphere. Record water content by Karl Fischer if critical (Not specified for this item; refer to CoA/Spec Sheet).

Reaction and Applications

This multifunctional building block combines an ortho-phenol with an aldehyde and an aryl bromide, enabling orthogonal transformations.

Representative application families (literature/general)

• Imine/Schiff base formation: Condense with primary amines/anilines to give o-hydroxy imines (salicylidene imines), precursors to chelating ligands (e.g., salen-type, N,O-bidentate). Intramolecular H-bonding can enhance imine stability.
• Cross-coupling at C–Br: Suzuki–Miyaura (to introduce aryl/alkenyl groups), Buchwald–Hartwig amination (Ar–N), Sonogashira (Ar–C≡C), Stille/Negishi couplings. Protect the phenol as silyl/benzyl ether if necessary to avoid catalyst deactivation.
• Electrophilic derivatization of –CHO: Formation of oximes, hydrazones, acylals; reduction to benzylic alcohols (NaBH4 mild; DIBAL-H/LAH alternatives); oxidation to the acid (e.g., Pinnick oxidation) or esterification via hemiacetal/acetal routes.
• O-Functionalization of phenol: Alkylation (Williamson ether), acylation (aroyl/acetyl) to tune electronics and solubility.
• Directed metalation/halogen–lithium exchange: The Ar–Br enables Li–Br exchange at low temperature (e.g., n-BuLi, −78 °C) followed by quench with electrophiles; ortho directors (–CHO/–OH) may influence regiochemistry—protect/coordinate accordingly.
• Knoevenagel condensations: With activated methylenes (e.g., malonates, cyanoacetates) to give arylidene adducts useful in materials and ligand design.

Use cases

• Ligand synthesis (salicylidene frameworks), fluorescent probes (ESIPT-capable scaffolds), and as a handle for late-stage diversification via the aryl bromide.

Reaction Conditions

General literature guidance for this scaffold (optimize for your system; not product specifications):

• Imine formation (Schiff base):

  • Solvent: ethanol, methanol, toluene (Dean–Stark), acetonitrile, or 2-MeTHF.
  • Conditions: equimolar amine and aldehyde; catalytic AcOH (0.1–0.5 eq) or molecular sieves (3Å). Temps: rt to reflux. Times: 0.5–12 h. Often high conversions; isolate as imine or proceed in situ.

• Suzuki–Miyaura coupling at Ar–Br:

  • Catalyst: Pd(PPh3)4 (1–3 mol%) or Pd-precatalyst with suitable ligand.
  • Base: K2CO3, K3PO4, Cs2CO3 (2–3 eq).
  • Solvent: dioxane/H2O, toluene/H2O, EtOH/H2O, or DMF. Temps: 60–100 °C. Time: 2–16 h. Phenol protection may be beneficial.

• Buchwald–Hartwig amination:

  • Catalyst/ligand: Pd2(dba)3 (1–2 mol%) with BINAP/XPhos/BrettPhos; base NaOtBu or Cs2CO3.
  • Solvent: toluene, dioxane, or DMAc. 80–120 °C, 4–18 h.

• Sonogashira coupling:

  • Catalyst: Pd(PPh3)2Cl2 (1–2 mol%) + CuI (2–5 mol%);
  • Base: Et3N, i-Pr2NH; solvent: THF, DMF, or acetonitrile; rt–60 °C.

• Li–Br exchange and trapping:

  • Reagent: n-BuLi (1.1 eq) at −78 °C in THF/Et2O; quench with electrophiles (CO2, DMF, aldehydes). Protect –OH as silyl ether to avoid deprotonation.

• Reductions/oxidations of –CHO:

  • Reduction: NaBH4 (MeOH/THF, 0–25 °C) to benzyl alcohol.
  • Oxidation: Pinnick (NaClO2/NaH2PO4, t-BuOH/H2O) to acid; or TEMPO/bleach for aldehyde to acid conversions.

Note: Yields and times vary with substrate and substitution; conduct small-scale optimization.

Safety and Handling

Authoritative safety information must be taken from the SDS. The following are general considerations for brominated aryl aldehydes/phenols.

Item-specific hazard information

• Signal word: Not specified for this item; refer to SDS.
• H-statements / GHS classification / pictograms: Not specified for this item; refer to SDS.

General handling guidance (literature/analogous compounds)

• Hazards: Aromatic aldehydes are irritants; phenolic –OH can be corrosive/irritant to skin/eyes. Brominated aromatics may be harmful to aquatic life.
• PPE: Lab coat, nitrile gloves (change regularly), splash goggles. Work in a fume hood to avoid inhalation of vapors or dust.
• Incompatibilities: Strong oxidizers (risk of over-oxidation of –CHO/phenol), strong bases (may induce O-alkylation/acylation side reactions), strong reducing agents (can reduce aldehyde). Avoid prolonged exposure to air and light to limit oxidative formation of the corresponding carboxylic acid.
• First aid (overview): Skin/eye contact—rinse with water for ≥15 min; remove contaminated clothing. Inhalation—move to fresh air. Ingestion—rinse mouth; do not induce vomiting; seek medical attention. Refer to SDS for detailed instructions.
• Spills: Avoid dust; collect using inert absorbent; dispose of according to local regulations.
• Fire: Combustible organic solid; use CO2, dry chemical, or foam. Thermal decomposition may release CO/CO2 and HBr.

Storage

• Store tightly closed at room temperature as specified. Protect from light and moisture. Consider storing under inert gas to minimize oxidation of the aldehyde (good practice).

Solvent Selection

Compound type: moderately hydrophobic aryl aldehyde with phenolic –OH and aryl bromide.

Polarity/miscibility profile (general)

• Expected solubility: good in polar aprotic solvents (DMSO, DMF, NMP, acetonitrile), ethyl acetate, THF, and many chlorinated solvents (DCM, chloroform); moderate in alcohols; poor in water.
• Acid/base behavior: phenolic –OH is weakly acidic; deprotonates in basic media, enhancing solubility in basic polar solvents.

Choosing solvents by task

• Imine/Schiff base formation: ethanol, methanol, toluene (with Dean–Stark), acetonitrile, or 2-MeTHF. Trace acid catalysis (e.g., AcOH) often accelerates.
• Cross-coupling at Ar–Br: polar aprotics (DMF, DMAc, NMP), dioxane, toluene, or mixed aqueous-organic systems with appropriate base.
• O-alkylation/acylation of phenol: acetone, acetonitrile, DMF with K2CO3/Na2CO3 or stronger base as required.

Comparison (general guidance)

• DMSO/DMF: highest solvating power for polar reactions; difficult workup.
• THF/2-MeTHF: good balance of solubility and greener profile; compatible with bases and organometallics.
• Ethanol/i-PrOH: greener, protic; suitable for condensations but may reduce rates for some couplings.

Note: Exact solubility parameters for this specific item are Not specified; optimize empirically and consult the CoA/Spec Sheet if available.

Storage and Reconstitution

Item-specific storage

• Storage conditions: Room temperature (as provided). Store in a tightly closed container.

Good-practice handling for aryl aldehydes (general)

• Protect from light, air, and moisture to minimize oxidation of the aldehyde to the corresponding acid and to prevent phenol oxidation. Consider storing under inert gas (N2/Ar) with a desiccant.
• If long-term storage is needed, keep in amber glass in a desiccator; minimize headspace oxygen.

Reconstitution and solution handling (general)

• Solvents: Readily prepared stock solutions in DMSO, DMF, acetonitrile, THF, ethanol, or ethyl acetate. Water solubility is expected to be low; use a cosolvent strategy for aqueous systems.
• Concentrations: Prepare concentrated stocks (e.g., 10–100 mM) in dry solvent; filter if particulates are present.
• Stability: Aldehyde-containing solutions can slowly degrade via oxidation or polymerization; prepare fresh solutions as needed and store aliquots at ≤4 °C, protected from light. Avoid basic aqueous media if aldehyde integrity is critical.

Shipping

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

Research Use Only: Not for human or veterinary use.

Structure and Identity

Brief: 4-Bromo-2-hydroxy-5-methylbenzaldehyde is a brominated salicylaldehyde derivative bearing ortho-phenolic and formyl functionalities, useful as a bifunctional aromatic building block.

Item-specific (from Product Data)

• SKU: B980833
• Product name: 4-Bromo-2-hydroxy-5-methylbenzaldehyde
• CAS: 1427373-22-5
• PubChem CID: 130063132
• InChIKey: 159404 (as provided)
• SMILES: Not specified for this item; refer to CoA/Spec Sheet.

Computed/Literature structural data (for reference; not item specifications)

• Typical molecular formula (literature): C8H7BrO2
• Typical molecular weight (literature): ~215.04 g/mol
• Core scaffold: substituted benzaldehyde (benzene ring bearing –CHO at C1)
• Substituents and regiochemistry: 2-hydroxy (ortho to aldehyde), 4-bromo (para to aldehyde), 5-methyl (meta to aldehyde)
• Key functional groups: aldehyde (–CHO), phenol (–OH), aryl bromide (–Br), aryl methyl (–CH3)

2D structural description (general)

• A benzene ring with four ring substituents: at position 1 an aldehyde; position 2 a phenolic –OH enabling intramolecular O–H···O=C hydrogen bonding; position 4 a bromine atom; position 5 a methyl group. The remaining two ring carbons carry hydrogens. The juxtaposition of o-OH and –CHO often stabilizes a six-membered intramolecular H-bonded conformation, influencing reactivity (e.g., imine formation and metal chelation).

Synthetic Utility

Functional group synergy

• Aldehyde (–CHO): versatile handle for condensations (imines/oximes/hydrazones), reductions to benzylic alcohols, oxidations to acids/esters, and C–C bond formations (Knoevenagel, Wittig/Still–Gennari after conversion to phosphonium salt if desired).
• Phenol (–OH): enables O-alkylation/acylation, ether formation, and metal chelation in ligand frameworks; can be protected as silyl (TBS/TBDPS) or benzyl ethers.
• Aryl bromide (–Br): gateway to cross-coupling (Suzuki/Negishi/Stille/Buchwald–Hartwig/Sonogashira) or metal–halogen exchange to introduce diverse substituents.

Retrosynthetic leverage

• The orthogonal nature of –Br and –CHO allows staged diversification: e.g., (1) protect –OH, (2) cross-couple at –Br, (3) condense –CHO with amines to give imines/salen-type ligands, then (4) deprotect –OH for chelation.

Materials and ligand design

• o-Hydroxybenzaldehyde cores furnish Schiff-base ligands that chelate metals (Ni, Cu, Zn, rare earths) for catalysis, magnetic materials, and sensing. The 4-bromo substituent enables late-stage tuning of electronics and sterics without perturbing the chelating motif.

Analytical cues

• Strong aldehyde 1H singlet near 10 ppm; phenolic OH often broad/downfield due to intramolecular H-bonding; 13C ~190–200 ppm for carbonyl. Useful for rapid reaction monitoring.

Target Specificity

Not applicable. This product is a small-molecule building block and is not an antibody, enzyme, or biologic. No target specificity, epitope, or isotype information applies.