5-Methyl-2-nitrobenzaldehyde - ≥97% , CAS No.5858-28-6

CAS: 5858-28-6 Cat. No.: M194081 Formula: C₈H₇NO₃ Peso molecolare: 165.15 Numero EC: 849-921-7

GRADE & PURITY ≥97%

Synonyms

5-Methyl-2-nitrobenzaldehyde | 5-methyl-2-nitro-benzaldehyde | 3-Methyl-6-nitrobenzaldehyde | MFCD08703362 | AKOS006229324 | DS-12498 | 3-methyl-6-nitrobenzaldehyde; 3-formyl-p-nitrotoluene; 6-Nitro-m-toluylaldehyd; 2-Nitro-5-methylbenzaldehyde; 5-Methyl-

Storage

Room temperature

Shipped In

Normal

Specifications

Sinonimi

5-Methyl-2-nitrobenzaldehyde | 5-methyl-2-nitro-benzaldehyde | 3-Methyl-6-nitrobenzaldehyde | MFCD08703362 | AKOS006229324 | DS-12498 | 3-methyl-6-nitrobenzaldehyde; 3-formyl-p-nitrotoluene; 6-Nitro-m-toluylaldehyd; 2-Nitro-5-methylbenzaldehyde; 5-Methyl-

Specifiche e purezza

≥97%

Condizioni di conservazione di stoccaggio

Room temperature

Spedito in

Normal

Purezza

≥97%

Nomi e identificatori

Sorrisi canonici

CC1=CC(=C(C=C1)[N+](=O)[O-])C=O

IUPAC Name

5-methyl-2-nitrobenzaldehyde

InChIKey

SKQIOXLCRQVPAT-UHFFFAOYSA-N

INCHI

1S/C8H7NO3/c1-6-2-3-8(9(11)12)7(4-6)5-10/h2-5H,1H3

Isomeri SMILES

CC1=CC(=C(C=C1)[N+](=O)[O-])C=O

Peso molecolare

165.15

Reaxy-Rn

2440158

Reaxys-RN_link_address

https://www.reaxys.com/reaxys/secured/hopinto.do?context=S&query=IDE.XRN=2440158&ln=

Taxonomic Classification

Taxonomy Tree

• Kingdom Organic compounds
  • Superclass Benzenoids
    • Classe Benzene and substituted derivatives
      • Subclass Nitrobenzenes

• Kingdom: Organic compounds
• Superclass: Benzenoids
• Classe: Benzene and substituted derivatives
• Subclass: Nitrobenzenes
• Intermediate Tree Nodes: Not available
• Direct Parent: Nitrobenzaldehydes
• Alternative Parents: Nitrotoluenes Nitroaromatic compounds Benzoyl derivatives Benzaldehydes Propargyl-type 1,3-dipolar organic compounds Organic oxoazanium compounds Organonitrogen compounds Organic salts Organic oxides Hydrocarbon derivatives Organic cations
• Molecular Framework: Aromatic homomonocyclic compounds
• Substituents: Nitrobenzaldehyde - Nitrotoluene - Benzaldehyde - Nitroaromatic compound - Benzoyl - Toluene - Aryl-aldehyde - C-nitro compound - Organic nitro compound - Organic oxoazanium - Allyl-type 1,3-dipolar organic compound - Propargyl-type 1,3-dipolar organic compound - Organic 1,3-dipolar compound - Organic salt - Hydrocarbon derivative - Organooxygen compound - Organonitrogen compound - Aldehyde - Organic oxide - Organic nitrogen compound - Organic oxygen compound - Organic cation - Aromatic homomonocyclic compound
• Descrizione: This compound belongs to the class of organic compounds known as nitrobenzaldehydes. These are nitrobenzenes that carry an aldehyde group at any position of the benzene ring.
• 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

Proprietà chimiche e fisiche

• Peso molecolare: 165.150 g/mol
• XLogP3: 1.600
• Hydrogen Bond Donor Count: 0
• Hydrogen Bond Acceptor Count: 3
• Rotatable Bond Count: 1
• Exact Mass: 165.043 Da
• Monoisotopic Mass: 165.043 Da
• Topological Polar Surface Area: 62.900 Ų
• Heavy Atom Count: 12
• Formal Charge: 0
• Complexity: 187.000
• 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

There are no standardized biological assay protocols associated with this small-molecule building block in the Product Data.

• Synthetic usage examples (general guidance; not item-specific)

  • Knoevenagel condensation (typical lab-scale): Combine the aldehyde (1.0 equiv) and malononitrile (1.1–1.5 equiv) in ethanol; add piperidine (10 mol%); stir at rt–reflux 2–4 h; monitor by TLC/HPLC; quench with dilute acid; isolate by filtration or extraction; recrystallize from EtOH.
  • Wittig olefination: Generate ylide from phosphonium salt (1.2 equiv) with n-BuLi (1.2 equiv) in anhydrous THF at 0 °C; add aldehyde (1.0 equiv); warm to rt and stir 2–16 h; work up with aqueous NH4Cl; purify by chromatography.

• Notes

  • The above are illustrative literature-style workflows. Optimize stoichiometry, solvent, and temperature for your specific substrate and safety constraints.
  • For any scale-up, perform calorimetry and risk assessment, and consult the SDS.

Biological Roles

This product is intended for research and synthetic laboratory use. It is not a biochemical reagent with defined endogenous roles.

• General context (literature)

  • Aromatic aldehydes with nitro substituents are synthetic intermediates rather than metabolites; they are not known to participate in primary metabolic pathways.
  • The aldehyde functional group can react with amines to form imines/Schiff bases; such reactivity is leveraged in chemical biology derivatizations but is not indicative of a native biological function for this compound.

• Practical note

  • If using in probe or ligand synthesis, evaluate cytotoxicity and off-target reactivity of the aldehyde moiety separately; avoid making biological activity claims without dedicated studies.

Buffer Applications

Not typically applicable. 5-Methyl-2-nitrobenzaldehyde is a hydrophobic aromatic aldehyde used as a synthetic building block and is not employed as a buffering agent.

• Guidance
  • For aqueous work, it may be dissolved in miscible co-solvents (e.g., DMSO, ethanol) and then diluted into buffer for assay development, but the compound itself does not provide buffering capacity.
  • Select standard biological buffers (PBS, HEPES, Tris) as appropriate for your system; confirm compound solubility and stability in the chosen medium.

Green Alternatives

Greener practice for this building block centers on solvent and reagent choices, since the substrate is fixed by target structure.

• Preferred greener solvents (literature/general)

  • Replace THF with 2-methyltetrahydrofuran (2-MeTHF) or cyclopentyl methyl ether (CPME) in Wittig/HWE condensations; they offer better EHS profiles and are derived from biomass (2-MeTHF).
  • Use ethanol or water–ethanol mixtures for Knoevenagel condensations with secondary amine catalysis, minimizing halogenated solvent use.
  • Favor ethyl acetate or toluene over dichloromethane where feasible for workups and recrystallizations.

• Greener reagents/conditions

  • Employ organocatalysis (e.g., L-proline, ammonium acetate) for condensation reactions instead of strong bases; run at ambient temperature where possible.
  • For selective carbonyl reductions, avoid catalytic hydrogenation to preserve –NO2; use milder hydrides and recyclable solvents to reduce energy input and waste.

• Trade-offs

  • 2-MeTHF/CPME can alter reaction rates/selectivity and may require longer times or adjusted bases.
  • Ethanol–water systems can increase byproduct hydration or hemiacetal formation; careful control of water content and temperature is needed.

• Snapshot comparison (general guidance)

  • THF -> 2-MeTHF: similar polarity, higher boiling point, improved safety; may slow some anionic reactions.
  • DCM -> EtOAc: reduced toxicity and environmental impact; may require larger volumes due to solubility differences.
  • Acetonitrile -> Ethanol: greener but more protic; can affect base strength and reaction equilibria.

Pharmaceutical Uses

No pharmacopeial status or excipient role is provided in the Product Data. This compound is sold for research use only and is not intended for human or veterinary use.

• General context (literature)

  • Aromatic nitrobenzaldehydes may appear as intermediates in the synthesis of active pharmaceutical ingredient (API) candidates, dyes, and fine chemicals. Their roles are typically as transient building blocks that are transformed during manufacturing.

• Formulation notes

  • If used in preclinical chemistry as an intermediate, ensure removal to below relevant impurity thresholds in final drug substance in accordance with ICH guidelines (e.g., nitroaromatic impurity assessments).

Physical Properties

Item-specific specifications (grade, purity, appearance, exact constants) are not provided in the Product Data for this SKU. Do not treat any typical values as specifications.

• Item-specific (from Product Data)

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

• Literature/general properties for 5-methyl-2-nitrobenzaldehyde (for informational context only; not product specs)

  • Phase at ambient conditions: aromatic aldehydes of this class are often low-melting solids or high-boiling liquids; exact MP/BP should be confirmed from CoA/SDS for this lot.
  • Solubility (qualitative): typically sparingly soluble in water; soluble in common organic solvents (e.g., ethanol, methanol, acetone, ethyl acetate, dichloromethane, toluene, DMF, DMSO). Actual solubility limits should be verified experimentally.
  • Density, refractive index, logP, pKa: Not specified here; consult literature or measure as needed for process design.

• Practical notes (general)

  • The aldehyde carbonyl can undergo oxidation to carboxylic acid and condensation/polymerization upon prolonged exposure to air/light/trace base; maintain closed containers.
  • Nitroaromatics can show polymorphism or oiling-out near the melting point; for crystallization studies, screen solvent mixtures (e.g., EtOAc/hexanes, toluene/hexanes, EtOH/water).

Quality and Grades

The Product Data do not specify a grade or purity for this SKU; treat any needed parameters as project-specific and verify using the CoA.

• Item-specific (from Product Data)

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

• Guidance on common grades for fine-organic building blocks (general)

  • Research grade: suitable for routine synthesis; assay typically by NMR/GC/HPLC; residual solvents and trace impurities present at typical research levels.
  • 95–99% nominal purity lots: adequate for most synthetic steps; consider in-process purification (trituration/recrystallization or column chromatography) when using in multistep sequences.
  • Low-UV/HPLC grade (if applicable): minimized UV-active impurities for analytical applications; not specified for this item.

• Stabilizers/inhibitors

  • No stabilizer is noted in the Product Data. Aromatic aldehydes generally do not require inhibitors; however, limiting air/light exposure can slow oxidation to the corresponding carboxylic acid.

• Recommended quality control on receipt (best practice)

  • Identity confirmation: 1H/13C NMR (diagnostic aldehyde proton ~9.7–10.2 ppm, literature), IR (C=O ~1690–1720 cm−1), HRMS.
  • Purity check: HPLC/GC and melting point (if solid). Record appearance and any odor changes over time.

Reaction and Applications

5-Methyl-2-nitrobenzaldehyde is a versatile electrophilic building block combining an aldehyde (reactive carbonyl) with a strongly deactivating, meta-directing nitro group and a weakly activating methyl substituent.

• Carbonyl transformations (literature/general)

  • Olefination: participates in Wittig, Horner–Wadsworth–Emmons, and Tebbe reactions to form substituted styrenes or nitrostilbene motifs. The ortho nitro can influence E/Z selectivity via electronic effects.
  • Condensations: effective in Knoevenagel (with active methylenes: malononitrile, ethyl cyanoacetate, Meldrum’s acid), Perkin, and aldol-type condensations; piperidine or ammonium acetate often used as catalysts in alcohols or acetic anhydride.
  • Nucleophilic additions: cyanohydrin, bisulfite adduct formation for purification/derivatization; addition of organometallics (RMgX/RLi) requires protection of –NO2 or carefully tuned conditions due to nitro sensitivity.

• Nitro group as a handle

  • Reduction of –NO2 to an aniline enables intramolecular cyclizations (e.g., to benzoxazoles/benzimidazoles after appropriate functionalization) or subsequent diazotization and cross-coupling.
  • Nucleophilic aromatic substitution (SNAr) is generally unfavored without additional leaving groups; however, –NO2 increases ring electrophilicity to facilitate directed ortho-metalation adjacent to methyl for further elaboration.

• Cross-coupling strategies

  • After converting the arene to a halogenated derivative (e.g., via electrophilic bromination at the 4- or 6-position dictated by substituent pattern), Suzuki/Heck/Sonogashira can append side chains while retaining the aldehyde (with protective handling to prevent decarbonylation).

• Representative uses (reported in literature)

  • Synthesis of nitrostilbene precursors for nonlinear optical materials.
  • Intermediates in dye, flavor/fragrance analog libraries, and heterocycle scaffolds (e.g., quinazolines, indazoles) via condensation and subsequent reduction steps.

Reaction Conditions

General literature conditions for key transformations of 5-methyl-2-nitrobenzaldehyde are summarized below (guidance only; optimize per substrate and scale). These are not item-specific specifications.

• Wittig/Horner–Wadsworth–Emmons olefination

  • Solvent: THF, toluene, DCM, or 2-MeTHF (green alternative); anhydrous.
  • Base: NaHMDS, n-BuLi (for ylide generation) or DBU/NaH (HWE phosphonates).
  • Temperature: −78 to 25 °C (Wittig); 0 to 60 °C (HWE). Typical times: 1–16 h.
  • Notes: Electron-poor aryl aldehydes often give high E-selectivity in HWE.

• Knoevenagel condensation (with malononitrile/ethyl cyanoacetate)

  • Solvent: EtOH, i-PrOH, MeCN, or EtOH/H2O.
  • Catalyst: piperidine, morpholine, ammonium acetate, or L-proline (5–20 mol%).
  • Temperature/time: rt to reflux, 1–6 h.
  • Notes: Remove water (Dean–Stark in toluene) to drive equilibrium if necessary.

• Selective carbonyl reduction (preserving –NO2)

  • Reagents: NaBH4 (in MeOH/EtOH) at 0–25 °C, minutes to hours; DIBAL-H in toluene/THF at −78 to 0 °C.
  • Notes: Avoid catalytic hydrogenation if –NO2 retention is required; risk of nitro reduction.

• Nitro reduction to aniline

  • Reagents: Fe/HCl or SnCl2/HCl in EtOH/H2O (reflux, 1–4 h) or catalytic hydrogenation (Pd/C, H2, EtOH at rt–50 °C, 1–6 h).
  • Notes: Protect or transform the aldehyde first (e.g., as acetal) to prevent concurrent reduction/condensation.

• Benzylic oxidation (methyl to acid/aldehyde)

  • Reagents: KMnO4 (basic aqueous), SeO2 (allylic/benzylic), or TBHP with suitable catalysts.
  • Notes: Check compatibility with –NO2; over-oxidation may occur.

All conditions above are literature-style examples and must be adapted to your substrate, scale, and EHS constraints.

Safety and Handling

Always consult the SDS for authoritative safety information. The Product Data do not list GHS elements for this item.

• Item-specific (from Product Data)

  • GHS Classification, Signal Word, H-Statements, Pictograms: Not specified for this item; refer to SDS.

• General hazards for nitro-substituted aromatic aldehydes (literature/experience; not product-specific)

  • Likely hazards: skin/eye irritation; harmful if swallowed; may cause respiratory irritation; combustible solid/liquid depending on melting range.
  • Sensitization: not typically classified, but avoid repeated skin contact.
  • Environmental: avoid release to the environment; nitro aromatics may be harmful to aquatic life.

• Handling recommendations

  • PPE: lab coat, safety glasses or goggles, nitrile gloves; use in a fume hood to avoid inhalation of vapors/dust.
  • Incompatibilities: strong oxidizers (risk of vigorous reaction/over-oxidation); strong bases (aldol-type self-condensation of aldehyde); strong reducing agents (could reduce –NO2 to –NH2); reactive metals.
  • Special risks: aldehydes can form peracid intermediates on oxidation; nitro group reduces under catalytic hydrogenation—plan accordingly if hydrogenation steps are nearby.

• First aid (overview; defer to SDS)

  • Inhalation: move to fresh air; seek medical advice if symptoms persist.
  • Skin/eye contact: rinse with water for 15 minutes; remove contaminated clothing; obtain medical attention for irritation.
  • Ingestion: rinse mouth; do not induce vomiting; seek medical attention.

• Fire-fighting

  • Use dry chemical, CO2, or alcohol-resistant foam; combustion may produce NOx and CO/CO2.

Solvent Selection

As a moderately polar, aromatic aldehyde with a nitro substituent, the compound exhibits good solubility in many organic media but negligible solubility in water.

• Polarity and miscibility (general, literature-based)

  • Soluble: DCM, chloroform, ethyl acetate, acetone, acetonitrile, toluene, THF, DMF, DMSO, alcohols (MeOH/EtOH) to varying extents.
  • Poorly soluble: aliphatic hydrocarbons (hexanes/heptane) unless warmed or used as anti-solvents in mixtures; water.

• Choosing solvents by application

  • Carbonyl olefinations (Wittig/HWE): THF, toluene, or DCM under anhydrous conditions. For greener profiles, 2-MeTHF or CPME can substitute THF.
  • Knoevenagel/aldol-type condensations: EtOH, i-PrOH, or MeCN are common; aqueous ethanol can work with secondary amine catalysts (e.g., piperidine) under reflux.
  • Nucleophilic additions (cyanohydrin, bisulfite adducts): aqueous-organic biphasic systems (EtOH/water) can be effective; monitor for hydrolysis.
  • Reduction chemistry: for selective C=O reduction without affecting –NO2, use non-protic, non-coordinating solvents (EtOAc, toluene) with mild hydride sources (e.g., NaBH(OAc)3 typically unreactive toward aldehydes; DIBAL or NaBH4 under controlled conditions in MeOH/EtOH can reduce the aldehyde—avoid catalytic hydrogenation if –NO2 retention is required).

• Practical tips

  • Dry solvents for base- or anion-mediated reactions to avoid competing hydrate formation of the aldehyde.
  • For crystallizations, start with EtOAc/hexanes or toluene/hexanes; adjust ratios by solubility screening.

Storage and Reconstitution

Item-specific storage conditions are provided; other details should be confirmed on the CoA/SDS.

• Item-specific (from Product Data)

  • Storage Conditions: Room temperature
  • Shipped In: Normal

• General storage guidance for aromatic aldehydes (literature/best practice)

  • Keep tightly sealed under inert gas (nitrogen/argon) when possible to minimize air oxidation to the corresponding acid.
  • Store in amber glass away from heat and light to reduce photodegradation and maintain assay.
  • Avoid prolonged exposure to strong bases or acids in storage vessels; these can promote self-condensation or hydration.

• Reconstitution and solution handling (general)

  • Solubility: typically dissolves readily in DCM, EtOAc, MeOH/EtOH, THF, toluene, DMF, and DMSO. Water solubility is low.
  • Preparing stock solutions: For analytical or screening work, prepare stocks at 10–100 mM in dry DMSO or MeCN; aliquot and store at 2–8 °C or −20 °C as appropriate for your workflow. Minimize freeze–thaw cycles.
  • Stability of solutions: Aldehyde solutions in alcohols can slowly form acetals/hemiacetals; prepare fresh as needed. In basic media, condensations may occur.

• Shelf-life

  • Not specified for this item; refer to CoA/Spec Sheet. Periodic re-check of purity by NMR/HPLC is recommended for material stored >6–12 months.

Structure and Identity

Concise aromatic aldehyde bearing a nitro group ortho to the formyl and a methyl group meta to the formyl (IUPAC: 5-methyl-2-nitrobenzaldehyde).

• Item-specific (from Product Data)

  • SKU: M194081
  • Product Name: 5-Methyl-2-nitrobenzaldehyde
  • CAS: 5858-28-6
  • Storage Conditions: Room temperature
  • Shipped In: Normal
  • Research Use Note: For research use only
  • InChIKey: 338438 (as provided; note that this appears truncated vs typical 27-character InChIKey formats)
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.

• Computed/Literature identity details (general, for the named compound)

  • Molecular formula (literature): C8H7NO3
  • Molecular weight (literature): ~165.15 g/mol
  • Preferred name variants: 2-nitro-5-methylbenzaldehyde; o-nitro-p-tolualdehyde (descriptive)
  • Structural features:
    • Aromatic benzene core with three substituents: formyl (–CHO) at C1, nitro (–NO2) at C2 (ortho), and methyl (–CH3) at C5 (meta relative to –CHO).
    • Functional groups: aromatic aldehyde (electrophilic carbonyl), strongly deactivating nitro (meta-directing in EAS), and weakly activating methyl (ortho/para-directing in EAS).
    • 2D description: a planar phenyl ring; adjacent to the aldehyde carbonyl is an –NO2 group; across the ring (meta to –CHO) sits a methyl group.

• Notes

  • Where precise identifiers (full InChI, canonical SMILES) are required for registration or informatics, consult the product CoA/Spec Sheet or verify via CAS 5858-28-6 in primary databases. All non-item-specific values above are given as literature/general identifiers for the named structure.

Synthetic Utility

This substrate couples a reactive aldehyde with a deactivating nitro group and an activating methyl group, enabling orthogonal reactivity on the aryl ring and the side chain.

• Functional group reactivity (literature/general)

  • Aldehyde: undergoes nucleophilic additions (organometallics with care), condensations (Wittig/HWE, Knoevenagel, Perkin), and oxidations (to acid using e.g., Oxone, NaClO2 with 2-methyl-2-butene, or KMnO4—mind –NO2 compatibility).
  • Nitro: reducible to an aniline (Fe/HCl, SnCl2, catalytic hydrogenation, or transfer hydrogenation), unlocking diazotization, coupling, or intramolecular cyclizations. Chemoselective reductions (C=O vs –NO2) require careful reagent choice.
  • Methyl: susceptible to benzylic oxidation (e.g., to acid via KMnO4/Na2Cr2O7 or to aldehyde via SeO2/TBHP), and to directed ortho-metalation enabling further substitution on the ring.

• Regioselectivity and directing effects

  • The –NO2 group is strongly meta-directing and deactivating in EAS; –CH3 is ortho/para-directing and activating. Halogenation or nitration (if pursued) will be guided by the combined directing effects.

• Retrosynthetic value

  • Disconnections via Wittig/HWE give access to vinyl nitroarenes and stilbenes; reduction of –NO2 then permits further cross-coupling after diazotization.
  • The aldehyde can serve as a convergent point for fragment assembly with enolizable partners, enabling rapid library generation for SAR studies.

• Purification strategies

  • Aldehydes can be purified as bisulfite adducts for removal of non-carbonyl impurities; regenerate by basification. Crystallization from EtOAc/hexanes is commonly effective, subject to screening.

Target Specificity

Not applicable. This product is a small-molecule building block and is not an antibody, enzyme, or affinity reagent with defined biological targets.

• Item-specific (from Product Data)
  • No target, clone, isotype, or species reactivity information is provided or expected for this chemical reagent.