2-Methyl-2-butene (Trimethylethylene)

2-Methyl-2-butene is a branched C₅ alkene with diverse applications in organic synthesis and chemical research.

Primary applications:

• Organic synthesis: Substrate for electrophilic additions, epoxidation, hydrogenation, and hydroboration
• Catalytic studies: Model compound for catalyst screening and mechanism investigations
• Polymer chemistry: Monomer for cationic polymerization and copolymer synthesis
• Carbocation chemistry: Scavenger for carbocation intermediates in superacid studies
• Pharmaceutical synthesis: Building block for drug intermediates and natural products
• Analytical chemistry: GC/MS standard and reference material

Why 2-methyl-2-butene? The tetrasubstituted double bond makes it ideal for studying steric effects, with three methyl groups providing significant steric hindrance that influences reactivity and selectivity in alkene transformations.

ChemContract supplies 2-Methyl-2-butene at >95% purity, verified by gas chromatography.

Quality control methods:

• Gas chromatography (GC): Purity >95% by peak area
• ¹H NMR spectroscopy: Structural confirmation
• ¹³C NMR spectroscopy: Carbon skeleton verification
• Density measurement: 0.660-0.665 g/mL at 20°C
• Refractive index: n²⁰/D ~1.387
• Water content: Karl Fischer (<0.05%)
• Peroxide test: <10 ppm

Certificate of Analysis includes:

• Batch number and manufacturing date
• GC chromatogram with purity calculation
• Physical properties (density, refractive index, boiling point)
• NMR spectra (¹H and ¹³C)
• Water and peroxide content
• Storage recommendations and safety data

2-Methyl-2-butene is a volatile, flammable liquid with well-defined physical characteristics.

Physical properties:

• Appearance: Clear, colorless liquid
• Molecular formula: C₅H₁₀
• Molecular weight: 70.13 g/mol
• Boiling point: 38-39°C at 760 mmHg
• Melting point: -133.8°C
• Density: 0.662 g/mL at 20°C
• Refractive index: n²⁰/D 1.387
• Flash point: -54°C (highly flammable)
• Vapor pressure: ~600 mmHg at 25°C

Solubility:

• Water: Practically insoluble (~0.013 g/100mL)
• Organic solvents: Miscible with ethanol, ether, acetone, hydrocarbons

Handling considerations: The low boiling point (38-39°C) means this compound is volatile at room temperature. Store in a cool place and use appropriate sealed containers to minimize evaporation.

2-Methyl-2-butene is highly flammable and requires proper safety precautions.

Storage conditions:

• Temperature: Cool storage (2-8°C preferred) to minimize evaporation
• Container: Tightly sealed bottle
• Atmosphere: Under nitrogen to prevent oxidation
• Location: Flammable liquid storage cabinet
• Shelf life: 12 months when stored properly

Safety precautions:

• Flammability: Keep away from heat, sparks, open flames, and hot surfaces
• Ventilation: Use only in well-ventilated areas or fume hood
• PPE: Safety glasses, chemical-resistant gloves, lab coat
• Grounding: Ground/bond containers during transfer
• Static: Use explosion-proof electrical equipment

Handling tips:

• Transfer in fume hood or well-ventilated area
• Use graduated cylinders or syringes for measurement
• Keep containers tightly closed when not in use
• Avoid breathing vapors
• Do not eat, drink, or smoke when handling

Peroxide formation: Like many alkenes, 2-methyl-2-butene can form peroxides upon prolonged storage or exposure to air. Our material is tested for peroxide content (<10 ppm) and stored under nitrogen to prevent formation.

2-Methyl-2-butene participates in typical alkene reactions with unique selectivity due to steric hindrance.

Common transformations:

• Hydrogenation: Pd/C, Pt/C → 2-methylbutane (isopentane)
• Epoxidation: mCPBA, H₂O₂ → 2,3-dimethyloxirane
• Hydroboration-oxidation: BH₃, then H₂O₂/NaOH → alcohols
• Halogenation: Br₂, Cl₂ → vicinal dihalides
• Hydrohalogenation: HBr, HCl → alkyl halides (Markovnikov)
• Ozonolysis: O₃, then reductive workup → acetone + acetaldehyde
• Dihydroxylation: OsO₄, KMnO₄ → diols

Steric effects:

• Tetrasubstituted double bond shows reduced reactivity in some additions
• Anti-Markovnikov additions may be favored in some cases due to steric factors
• Slower hydrogenation compared to less substituted alkenes
• Excellent model for studying steric effects in catalysis

Polymer chemistry:

• Cationic polymerization with Lewis acids (AlCl₃, BF₃)
• Copolymerization with isobutylene
• Chain transfer agent in polymerization

No, 2-methyl-2-butene is one of several C₅H₁₀ isomers with distinct properties.

C₅ Alkene isomers comparison:

• 1-Pentene: CH₂=CH-CH₂-CH₂-CH₃ (terminal, monosubstituted)
• 2-Pentene: CH₃-CH=CH-CH₂-CH₃ (internal, disubstituted, cis/trans)
• 2-Methyl-1-butene: CH₂=C(CH₃)-CH₂-CH₃ (terminal, disubstituted)
• 3-Methyl-1-butene: CH₂=CH-CH(CH₃)₂ (terminal, monosubstituted)
• 2-Methyl-2-butene: (CH₃)₂C=CH-CH₃ (internal, trisubstituted/tetrasubstituted)

What makes 2-methyl-2-butene unique:

• Most substituted: Three methyl groups on the double bond
• Most stable: Highest degree of substitution = most stable alkene
• Highest steric hindrance: Slowest in some reactions
• Lowest boiling point: 38-39°C (most volatile pentene)

Why it matters: The high degree of substitution and steric crowding make 2-methyl-2-butene ideal for mechanistic studies and understanding how sterics influence reactivity.

We offer multiple pack sizes for research applications.

Available quantities (in stock):

• 100 mL – Initial studies and method development
• 250 mL – Standard research quantity
• 500 mL – Extended research projects
• 1 L – Large-scale synthesis or multiple experiments
• Custom quantities: Available for industrial applications

Usage estimates:

• 100 mL = ~66 g (sufficient for 20-50 typical reactions)
• Density: 0.662 g/mL (light liquid)
• Typical reaction scale: 1-10 mL per experiment

Delivery times:

• Stock quantities: Ships within 24-48 hours
• Domestic USA: 2-3 business days (DOT compliant ground shipping)
• International: 5-10 business days (hazmat shipping regulations apply)
• Large quantities (>1L): 1-2 weeks

Shipping:

• Ships as hazmat/dangerous goods (flammable liquid, UN1993)
• DOT/IATA compliant packaging
• Ground shipping only (no air freight)
• Proper labeling and documentation included
• Certificate of Analysis included
• Safety Data Sheet included