Methyl 15-methylheptadecanoate , CAS No.54833-55-5

CAS: 54833-55-5 Cat. No.: M955059 Summenformel: C₁₉H₃₈O₂ Molekulargewicht: 298.500

Storage

Room temperature

Specifications

Storage

Room temperature

Namen und Kennungen

Kanonisches Lächeln

CCC(C)CCCCCCCCCCCCCC(=O)OC

IUPAC Name

methyl 15-methylheptadecanoate

InChIKey

NMNGCYQFGHXXPY-UHFFFAOYSA-N

INCHI

1S/C19H38O2/c1-4-18(2)16-14-12-10-8-6-5-7-9-11-13-15-17-19(20)21-3/h18H,4-17H2,1-3H3

Molekulargewicht

298.500

Taxonomic Classification

Taxonomy Tree

• Kingdom Organic compounds
  • Superclass Lipids and lipid-like molecules
    • Klasse Fatty Acyls
      • Subclass Fatty acid esters

• Kingdom: Organic compounds
• Superclass: Lipids and lipid-like molecules
• Klasse: Fatty Acyls
• Subclass: Fatty acid esters
• Intermediate Tree Nodes: Not available
• Direct Parent: Fatty acid methyl esters
• Alternative Parents: Methyl esters Monocarboxylic acids and derivatives Organic oxides Hydrocarbon derivatives Carbonyl compounds
• Molecular Framework: Aliphatic acyclic compounds
• Substituents: Fatty acid methyl ester - Methyl ester - Carboxylic acid ester - Monocarboxylic acid or derivatives - Carboxylic acid derivative - Organic oxygen compound - Organic oxide - Hydrocarbon derivative - Organooxygen compound - Carbonyl group - Aliphatic acyclic compound
• Beschreibung: This compound belongs to the class of organic compounds known as fatty acid methyl esters. These are compounds containing a fatty acid that is esterified with a methyl group. They have the general structure RC(=O)OR', where R=fatty aliphatic tail or organyl group and R'=methyl group.
• 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

Chemische und physikalische Eigenschaften

• Molekulargewicht: 298.500 g/mol
• XLogP3: 8.200
• Hydrogen Bond Donor Count: 0
• Hydrogen Bond Acceptor Count: 2
• Rotatable Bond Count: 16
• Exact Mass: 298.287 Da
• Monoisotopic Mass: 298.287 Da
• Topological Polar Surface Area: 26.300 Ų
• Heavy Atom Count: 21
• Formal Charge: 0
• Complexity: 226.000
• Isotope Atom Count: 0
• Defined Atom Stereocenter Count: 0
• Undefined Atom Stereocenter Count: 1
• 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

No item-specific tested protocols are provided for this product.

General laboratory uses (literature/practice; not product-validated):

• GC-FID standard preparation: dissolve at 1–5 mg/mL in iso-octane or hexane; inject 0.1–1 µL under your method’s conditions; verify retention time and purity prior to quantitative use.
• Stock solutions for assays: prepare 10–100 mM stocks in ethanol, DMSO, or isooctane; vortex/sonicate to aid dissolution; store aliquots at RT or 2–8 C protected from light and air.
• Saponification to free acid prior to conjugation: treat with 1–2 M KOH in MeOH/H2O (9:1) for 1–2 h at 25–40 C; acidify and extract; dry and use immediately for coupling.

For validated, application-specific SOPs, consult peer-reviewed literature or develop internal methods. Always confirm suitability and performance in your system.

Biological Roles

Item is supplied for research use only. The following provides biochemical context for branched-chain fatty acid methyl esters (FAMEs) and their parent fatty acids (literature/general information; not product use claims):

• Origin and occurrence: 15-Methylheptadecanoic acid is an iso-branched saturated fatty acid (i-18:0 equivalent). Iso- and anteiso-branched fatty acids are common in bacterial membranes (e.g., Bacillus and Staphylococcus species), where they modulate membrane fluidity and low-temperature adaptability.
• Analytical role of the methyl ester: The methyl ester derivative is a standard form for GC-based lipid profiling. Methylation improves volatility and chromatographic behavior without altering the carbon count of the acyl chain. Branching leads to characteristic retention time shifts relative to straight-chain homologs and distinctive EI-MS fragmentation patterns useful for isomer identification.
• Metabolic considerations: In biological systems, free fatty acids are typically esterified to glycerolipids or converted to acyl-CoA thioesters. Exogenous FAMEs generally require hydrolysis (by esterases/lipases) to release the free acid before entering β-oxidation or remodeling pathways; branched-chain acids are often metabolized more slowly and by specific bacterial pathways.
• Research applications: Standards for microbial lipidomics; tracers in studies of membrane biophysics of branched lipids; comparison probes for how branching affects lipid packing, melting, and phase behavior in model membranes.

No medical or clinical claims are made. For any biological work, ensure appropriate formulation (e.g., dissolve in ethanol/DMSO with nonionic carrier, or incorporate into liposomes) to address low aqueous solubility.

Buffer Applications

This compound is a highly hydrophobic fatty acid methyl ester and is not used to formulate aqueous buffer systems or to control pH.

• Not typically applicable: It lacks acid/base functionality in water and is essentially insoluble in aqueous buffers.
• Practical note: If incorporating into biochemical assays, prepare as a stock in a compatible organic solvent (e.g., ethanol, DMSO, or iso-octane) and add to aqueous systems with appropriate carriers (albumin, surfactants) to avoid precipitation, recognizing that this alters buffer composition and may affect assay results.

For pH buffering needs, select conventional buffer systems (e.g., phosphate, HEPES, Tris) unrelated to this reagent.

Green Alternatives

Because this is a reagent/substrate rather than a process solvent, “green alternatives” typically refer to greener methods for its preparation, handling, and transformations rather than replacing the compound itself.

Greener choices in common workflows (literature/general guidance):

• Esterification to prepare FAMEs:
  • Conventional: sulfuric acid in methanol, reflux; efficient but corrosive and generates acidic waste.
  • Greener alternative: solid acid catalysts (Amberlyst-15, sulfonated carbon) or enzyme-catalyzed methanolysis (lipases) at lower temperatures with easier workup.
• Transesterification/hydrolysis:
  • Conventional: NaOMe/MeOH (fast, moisture-sensitive) or KOH/EtOH (aqueous waste streams).
  • Greener alternative: ionic-liquid or deep eutectic solvent media; biocatalysis with immobilized lipases; supercritical MeOH with energy recovery (process-scale).
• Solvent considerations for analysis/prep:
  • Replace chlorinated solvents (CH2Cl2, chloroform) with ethyl acetate or cyclopentyl methyl ether (CPME) when feasible, acknowledging solubility trade-offs for very hydrophobic substrates.

Comparison (overview):

• Acid-catalyzed MeOH vs lipase-catalyzed:
  • Acid: fast, inexpensive; harsher conditions; neutralization/waste.
  • Lipase: milder, selective, recyclable catalysts; higher cost; potential longer reaction times.
• CH2Cl2 vs ethyl acetate for workup:
  • CH2Cl2: high solvency, easy phase separation; environmental/health concerns.
  • EtOAc: biodegradable, lower toxicity; may require warming or co-solvent to fully dissolve long-chain FAMEs.

Note: Selection should balance EHS profiles with analytical requirements (e.g., GC compatibility) and the high hydrophobicity of this FAME.

Pharmaceutical Uses

No pharmacopeial status or item-specific excipient designation is provided for this product; it is supplied for research use only.

General formulation context for long-chain FAMEs (literature; not product claims):

• Role as hydrophobic excipients: Saturated fatty acid esters can function as emollients or oil-phase components in topical or cosmetic prototypes. However, methyl esters are more volatile and less commonly used than higher esters (e.g., isopropyl myristate) in regulated products.
• Research/formulation screening: Branched-chain esters provide altered rheology and spreadability compared to straight-chain analogs. They may be evaluated in pre-formulation screenings for lipid-based delivery systems or as internal standards in analytical release testing of lipid formulations.
• Compatibility: Generally compatible with nonionic surfactants and hydrocarbon oils; may undergo slow hydrolysis in the presence of moisture and enzymes.

Caveats:

• Not specified for GMP use; Not specified for pharmacopeial compliance (USP/Ph.Eur.). Refer to CoA/Spec Sheet if such information becomes available.
• No therapeutic or clinical claims are made. Any use in formulation research should include appropriate safety and stability assessments and be restricted to non-clinical laboratory investigations.

Physical Properties

Item-specific specs: Not specified for this item; refer to CoA/Spec Sheet.

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

• Physical state: colorless to pale yellow oily liquid/low-melting solid at ambient conditions (literature, branched FAMEs often liquid at RT due to reduced packing).
• Molecular formula: C19H38O2 (literature for methyl 15-methylheptadecanoate).
• Molecular weight: ~298.50 g/mol (literature/computed from formula).
• Boiling point: typically >300 C at 1 atm; ~160–190 C at 1–2 mmHg (literature for C18–C19 saturated FAMEs; exact value depends on branch/isomer and pressure).
• Melting point: expected well below 30 C; many iso-branched C18 FAMEs are liquid at RT (literature trend).
• Density: ~0.85–0.87 g/mL at 20–25 C (literature range for long-chain FAMEs).
• Refractive index (n20 D): ~1.440–1.448 (literature range for saturated C18–C19 FAMEs).
• LogP (estimated): >7 (very hydrophobic; literature estimates for long-chain FAMEs).
• Solubility: insoluble in water; miscible with nonpolar solvents (hexane, heptane, isooctane); soluble in moderately nonpolar solvents (toluene, CH2Cl2, chloroform, ether); limited solubility in MeOH/EtOH unless warmed (literature experience).

General remarks:

• Values above are typical literature expectations for branched C19 FAMEs and provided for planning purposes. For exact batch-specific data, consult the item’s CoA/Spec Sheet.

Quality and Grades

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

Guidance on interpreting common grades for this compound type (general information; not product specifications):

• Research grade: suitable for general synthesis, lipid standards preparation, and method development where trace impurities at ppm–0.1% levels are tolerable.
• GC/Analytical grade (if offered): emphasizes low non-volatile residue, narrow distillation cut, and high purity for use as calibration standards in FAME profiling. Low background in FID/MS is critical.
• Isomeric purity: for branched-chain FAMEs, “positional isomer” and “iso vs anteiso” content can matter in microbial lipidomics; vendors may specify the branch location or provide NMR/GC-MS trace documentation. If your application is structure-sensitive, verify isomeric purity on the CoA.
• UV/LC grade: rarely specified for FAMEs, but if using in LC-UV methods, low UV-absorbing impurities and specified UV cutoff can be beneficial.

What to check on the CoA/Spec Sheet for this item:

• Purity assay methodology (GC-FID area %, quantitative NMR, or titrimetric ester value)
• Water content and residual solvents: Not specified for this item; refer to CoA/Spec Sheet.
• Stabilizers/inhibitors: Typically none for saturated FAMEs; Not specified for this item; refer to CoA/Spec Sheet.
• Storage and shipping conditions: Storage at room temperature is specified for this item; confirm any light/air precautions on the SDS.

Reaction and Applications

Applications (general for branched FAMEs; not item-specific performance claims):

• Lipid analysis: used as a reference standard or retention-time marker in GC-FID/GC-MS profiling of bacterial iso/anteiso-branched fatty acids. Branched chains help resolve peaks from straight-chain homologs.
• Model substrate: representative for studies on transesterification, base/acid-catalyzed hydrolysis, and hydrogenolysis relevant to biodiesel upgrading and lipid processing.
• Materials/lubricants research: branching modifies low-temperature flow and volatility, useful for structure–property correlations in base oils and surfactant precursors.

Transformations (synthetic context):

• Hydrolysis (saponification) to 15-methylheptadecanoic acid using aqueous base (KOH/NaOH) in MeOH/THF or EtOH/H2O.
• Transesterification to other alkyl esters (e.g., ethyl, isopropyl) via catalytic alcoholysis (NaOMe, K2CO3, or enzymes such as lipases under mild conditions).
• Reduction to the corresponding 15-methylheptadecanol (LiAlH4, DIBAL-H) or to hydrocarbon (Clemmensen/Wolff–Kishner after conversion to aldehyde; or catalytic hydrodeoxygenation, literature).
• Alpha-functionalization: enolate formation adjacent to the ester carbonyl under strong base (LDA) is in principle possible, though sterics and long-chain solubility can be limiting; typically not preferred for this substrate class.

Practical tips:

• Ensure dryness for base-catalyzed transesterification (alcohols and catalysts are water-sensitive).
• For GC standards, prepare solutions in iso-octane or hexane and verify purity/identity by GC-FID and EI-MS (characteristic M+ at m/z 298 for C19H38O2, literature) with expected branched-chain fragmentation.
• Branching generally lowers mp and improves GC peak shape vs straight-chain analogs of the same carbon count.

Reaction Conditions

General literature guidance for typical transformations of long-chain FAMEs (not product specifications):

• Base-catalyzed transesterification (MeOH ⇄ ROH exchange):
  • Conditions: 0.1–1.0 mol% NaOMe or KOMe in dry alcohol (e.g., EtOH, i-PrOH), 20–60 C, 0.5–4 h.
  • Notes: Minimize water; use slight excess of alcohol. Quench with NH4Cl and extract into hexane/EtOAc.
• Acid-catalyzed methanolysis/hydrolysis:
  • Conditions: 0.5–5 wt% H2SO4 in MeOH/H2O (80:20 to 95:5), reflux (65 C), 2–6 h for hydrolysis to acid.
  • Notes: Corrosive; neutralize and separate organic phase; consider solid acid catalysts as alternatives.
• Saponification to free acid:
  • Conditions: 1–2 M KOH in MeOH/H2O (9:1), 25–50 C, 1–3 h; then acidify to pH <2 with HCl, extract into hexane/EtOAc.
  • Typical yields: often >90% for homogeneous substrates (literature).
• Reduction to alcohol:
  • LiAlH4 (1.2–2.0 equiv) in dry THF or Et2O, 0 C to reflux, 1–3 h; work up carefully with water/Na2SO4·10H2O. Alternatively, DIBAL-H (2–3 equiv) at −78 to 0 C to stop at aldehyde.
• GC analysis (FAMEs):
  • Columns: nonpolar methyl silicone (e.g., DB-1, HP-1) or polar cyanopropyl (e.g., DB-23) for isomer separation.
  • Oven: 120–250 C gradient (e.g., 10 C/min) with carrier He/H2; injector 250–280 C; FID detection standard. Branched FAMEs show slightly shorter retention than straight-chain isomers of the same carbon count.

Solvent and workup considerations:

• Due to strong hydrophobicity, favor hexane/iso-octane/toluene for extractions. Warm mildly (30–40 C) to ensure dissolution before reactions. Use phase-transfer catalysts (e.g., TBAB) if conducting aqueous-base reactions in biphasic media.

Safety and Handling

Item-specific hazard data:

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

General safety considerations for fatty acid methyl esters (literature/practice; not product specifications):

• Hazard profile: typically low acute toxicity; combustible liquid. Can cause irritation on prolonged skin or eye contact. Spilled material may create slip hazards.
• Incompatibilities: strong oxidizing agents (risk of exotherm/combustion); strong bases or acids under heating (may catalyze transesterification/hydrolysis); avoid powerful reducing agents.
• Handling practices:
  • Use in a well-ventilated area or fume hood to avoid inhalation of mists/vapors when heated or nebulized.
  • Wear appropriate PPE: lab coat, safety glasses, and nitrile gloves; change gloves if contaminated.
  • Avoid open flames and hot surfaces; keep away from ignition sources. Ground/bond when transferring large volumes.
• First-aid overview (consult SDS for full guidance):
  • Inhalation: move to fresh air; seek medical attention if symptoms persist.
  • Skin contact: wash with soap and water; remove contaminated clothing.
  • Eye contact: rinse cautiously with water for several minutes; remove contact lenses if present and easy; seek attention if irritation continues.
  • Ingestion: rinse mouth; do not induce vomiting; seek medical advice.
• Fire-fighting: use dry chemical, CO2, foam. Burning may produce CO/CO2 and acrid smoke.
• Environmental: avoid release to drains; long-chain esters can form surface films and are persistent under some conditions.

Always defer to the product-specific SDS for authoritative safety, exposure limits, and response procedures.

Solvent Selection

This product is a hydrophobic, neutral, saturated fatty acid methyl ester. Solvent choice is usually driven by handling, analysis (GC), or transformation (hydrolysis, transesterification).

• Polarity and miscibility (literature/general):
  • Polarity: very low; behaves like a long-chain alkane with a weakly polar ester head.
  • Water: insoluble.
  • Miscible/soluble: hexane, heptane, isooctane, petroleum ether, toluene, CH2Cl2, chloroform, diethyl ether; moderate solubility in ethyl acetate; limited in MeOH/EtOH at RT (improves on warming or with co-solvent).
• Typical use scenarios:
  • GC sample preparation: dissolve in nonpolar, GC-compatible solvents (e.g., iso-octane, hexane) at 0.1–10 mg/mL; avoid high-boiling residues.
  • Saponification/hydrolysis: use MeOH/EtOH with catalytic base (KOH/NaOMe) or acid (H2SO4) and a co-solvent if needed to aid dissolution.
  • Purification: normal-phase silica gel with hexane/ethyl acetate gradients; the compound elutes late due to high hydrophobicity.
• Choosing among alternatives:
  • Iso-octane vs hexane: iso-octane offers lower volatility and often improved GC baseline stability; hexane provides faster evaporation.
  • CH2Cl2 vs toluene: CH2Cl2 dissolves efficiently at RT but is more volatile and regulated; toluene allows higher-temperature operations.

Small comparison (literature-based):

• Hexane: excellent solubility, fast evaporation, low polarity; flammable.
• Iso-octane: GC-friendly, good solubility, slightly higher bp; flammable.
• Toluene: good solubility, higher bp for reactions; stronger odor; regulated use in some labs.
• Ethyl acetate: moderate solubility; greener profile; may be insufficient alone at RT.

Storage and Reconstitution

Item-specific storage: Room temperature (as provided in Product Data). Shipped-in conditions: Not specified for this item; refer to CoA/Spec Sheet.

General storage guidance for branched saturated FAMEs (literature/practice; not product specifications):

• Stability: Saturated FAMEs are generally air-stable and resistant to autoxidation compared to unsaturated analogs. Nonetheless, minimize prolonged exposure to air, heat, and light to prevent slow hydrolysis or oxidative discoloration.
• Containers: Store in tightly sealed amber glass with PTFE-lined cap to limit moisture ingress and light exposure. For long-term storage or analytical standards, consider nitrogen headspace.
• Temperature: Ambient storage is typically acceptable. For multi-year storage or high-precision analytical use, 2–8 C can further enhance stability; avoid freezing that might complicate handling of viscous materials.
• Reconstitution/solubilization:
  • Recommended solvents: hexane, iso-octane, toluene, CH2Cl2, chloroform, or EtOAc. Warm gently (30–40 C) and vortex/sonicate if necessary to obtain clear solutions.
  • Aqueous systems: insoluble; if required, use co-solvents or carriers (surfactants, BSA) and validate homogeneity.
• Freeze–thaw: Not critical for neat liquids, but minimize repetitive heating/cooling cycles of solutions. Prepare single-use aliquots for analytical standards.

Always refer to the product’s CoA/Spec Sheet and SDS for definitive storage, stability, and handling instructions. Research use only.

Structure and Identity

Brief overview: Methyl 15-methylheptadecanoate is a saturated, branched long-chain fatty acid methyl ester (FAME), i.e., the methyl ester of 15-methylheptadecanoic acid (an iso-branched C18:0 fatty acid).

• Item-specific facts (from Product Data):

  • CAS: 54833-55-5
  • CID: 554152
  • InChIKey: 242402 (as provided)
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.

• Literature/computed identifiers and features (not item-specific):

  • Typical molecular formula (literature for this structure): C19H38O2 (isomeric with methyl stearate; branching does not change formula).
  • Typical molecular weight (literature): ~298.50 g/mol.
  • Functional groups: one fatty acid methyl ester (–CO2Me); no unsaturation; one internal methyl branch at C-15 relative to the carboxyl carbon (iso-branch near the terminal end).
  • Structural description (2D): a linear saturated C17 backbone bearing a methyl substituent at C-15 (counting from the carbonyl carbon as C-1), terminating in a methyl group at the ω-end; the carbonyl carbon is esterified with methanol to give –C(=O)–O–CH3. No rings; no heteroatoms beyond the ester oxygens; no stereocenters.

• General chemistry notes:

  • The 15-methyl branch modestly lowers melting point vs the straight-chain isomer by disrupting crystallinity.
  • As a FAME, it is neutral, nonpolar, and well-suited for GC analysis of fatty acid profiles.

Synthetic Utility

As a saturated, iso-branched fatty acid methyl ester, methyl 15-methylheptadecanoate is a versatile, hydrophobic building block and analytical standard.

Key reactivity (general literature):

• Ester functionality:
  • Hydrolysis/saponification to yield the free acid (15-methylheptadecanoic acid), enabling subsequent coupling to amines (amide formation via EDCI/DMAP, SOCl2 activation, or CDI) or to alcohols (re-esterification).
  • Reduction to alcohol (LiAlH4, DIBAL-H) or, via two-step reduction (to aldehyde then to alkane), conversion to the corresponding hydrocarbon for materials studies.
• Alpha chemistry: Enolate generation adjacent to the carbonyl can, in principle, allow acyl substitutions (Claisen-type condensations) though practical application is limited by solubility and steric hindrance from the long chain and branch.
• Chain modification: Ozonolysis/oxidation not applicable (no unsaturation). Radical functionalization at remote positions is generally inefficient; better approached by transforming the acid derivative after selective activation.

Utility in workflows:

• Internal/retention-time standard in GC-FID/GC-MS of microbial branched-chain fatty acids; assists peak assignment and quantitation.
• Hydrophobic tail donor: after hydrolysis, the acid can be coupled into surfactants, lipids, or polymer side chains to study effects of iso-branching on packing and melting.
• Model substrate for transesterification kinetics and green catalysis benchmarking, due to clean analytical response and thermal stability.

Practical notes:

• For coupling chemistry, convert the acid (post-saponification) to the acid chloride under mild conditions (oxalyl chloride, catalytic DMF), then react with nucleophiles at 0–25 C.
• Ensure adequate solubility by using nonpolar or biphasic systems; warming and co-solvents (toluene, THF) often required.

Target Specificity

Not applicable. This product is a small-molecule fatty acid methyl ester, not a biological affinity reagent. There are no antigens, epitopes, species reactivity, clones, or isotypes associated with this item.