1195-32-0

Basic information

• Product Name: ALPHA,P-DIMETHYLSTYRENE
• Synonyms: 2-(p-Methylphenyl)propene;2-p-Tolylpropene;4-isopropenyl-1-methylbenzene;4-Methyl-alpha-methylstyrene;alpha,4-Dimethylstyrene;Benzene, 1-methyl-4-(1-methylethenyl)-;benzene,1-methyl-4-(1-methylethenyl)-;Dehydro-p-cymene
• CAS NO: 1195-32-0
• Molecular Formula: C₁₀H₁₂
• Molecular Weight: 132.2
• EINECS: 214-795-9
• Product Categories: Alcohol& Phenol& Ethers;Alphabetical Listings;C-D;Flavors and Fragrances
• Mol File: 1195-32-0.mol

Chemical Properties

• Melting Point: −28 °C(lit.)
• Boiling Point: 186-189 °C(lit.)
• Flash Point: 144 °F
• Appearance: clear colorless to light yellow liquid
• Density: 0.904 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.834mmHg at 25°C
• Refractive Index: n20/D 1.535(lit.)
• Storage Temp.: Freezer
• Solubility: Chloroform (Slightly), Methanol (Slightly)
• Stability: Light Sensitive
• CAS DataBase Reference: ALPHA,P-DIMETHYLSTYRENE(CAS DataBase Reference)
• NIST Chemistry Reference: ALPHA,P-DIMETHYLSTYRENE(1195-32-0)
• EPA Substance Registry System: ALPHA,P-DIMETHYLSTYRENE(1195-32-0)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36-37/39
• WGK Germany: 2
• TSCA: Yes
• Hazardous Substances Data: 1195-32-0(Hazardous Substances Data)

Usage

Uses

Used in Flavor Industry:
ALPHA,P-DIMETHYLSTYRENE is used as a flavor compound for its unique taste characteristics, which contribute to the spicy, balsamic, musty, and eugenol/guiacol-like notes with a nutty nuance. It is particularly useful in creating complex and nuanced flavors for various food and beverage products.
Used in Fragrance Industry:
ALPHA,P-DIMETHYLSTYRENE is used as a fragrance ingredient for its citrusy-lemon-like aroma. It can be incorporated into various perfumes, colognes, and other scented products to provide a fresh and uplifting scent.
Used in Essential Oils:
ALPHA,P-DIMETHYLSTYRENE is used as a component in essential oils, such as those derived from litchi, distilled Mexican lime, and parsley. Its presence in these essential oils contributes to their distinct and pleasant aromas, making them valuable for use in aromatherapy and other applications.
Used in Research and Development:
Due to its unique chemical properties and aroma, ALPHA,P-DIMETHYLSTYRENE can be used in research and development for the creation of new flavor and fragrance compounds, as well as for studying its potential applications in other industries, such as pharmaceuticals or materials science.

Preparation

By passing a stream of p-cymene and water vapors over activated aluminum oxide at 730°C.

Synthesis Reference(s)

Journal of the American Chemical Society, 118, p. 3970, 1996 DOI: 10.1021/ja9600486The Journal of Organic Chemistry, 44, p. 3157, 1979 DOI: 10.1021/jo01332a014Synthetic Communications, 19, p. 3353, 1989 DOI: 10.1080/00397918908052740

InChI:InChI=1/C10H12/c1-8(2)10-6-4-9(3)5-7-10/h4-7H,1H2,2-3H3

Upstream product

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Relevant articles and documents

ADDITIONS OF SUBSTITUTED PHENYLTHIYL RADICALS TO SUBSTITUTED α-METHYLSTYRENES. GROUND STATE AND TRANSITION STATE ELECTRONIC EFFECTS

The radical addition of substituted thiophenols to α-methylstyrene and substituted α-methylstyrenes has been investigated at 70 deg C.Relative reactivities of pairs of thiophenols competing with individual alkenes can be utilized to obtain Hammett correlations.The interplay of substituent effects in alkene and thiyl radical leads to examples of non-linear rho values.Rationales for this behavior will be offered in terms of variable contributions from ground state and transition state electronic factors as well as in terms of possible mechanistic changes.

Bifunctional catalyst Pd-Al-MCM-41 for efficient dimerization-hydrogenation of β-pinene in one pot

A new type of bimetallic palladium and aluminum incorporated mobile crystalline materials (Pd-Al-MCM-41) as bifunctional catalysts has been hydrothermally synthesized. Characterization shows that these molecular materials exhibit an ordered mesoporous structure, high surface area and a good dispersion of palladium in the frame. The catalytic activity of the Pd-Al-MCM-41 for the dimerization-hydrogenation reaction system of β-pinene in one pot has been systematically studied. Pd0.5-Al30-MCM-41 (SiO2/Al2O3 = 30, 0.5 wt% palladium content) was found to be the best catalyst which gave a dimer yield of up to 64.7%. It is worth noting that palladium shows a good synergic catalytic effect with aluminum in the dimerization reaction and enhances the dimerization yield. Furthermore, the bifunctional catalyst displayed a good activity over 4 runs.

Synthesis of N-Alkylpyridin-4-ones and Thiazolo[3,2- a]pyridin-5-ones through Pummerer-Type Reactions

N-Alkylated 4-pyridones were obtained through a one-pot procedure involving either normal or interrupted Pummerer reactions between triflic anhydride-activated sulfoxides and 4-fluoropyridine derivatives, followed by hydrolysis. On the other hand, triflic anhydride-activated benzyl 6-fluoro-2-pyridyl sulfoxide could react with alkenes or alkynes to afford thiazolo[3,2-a]pyridin-5-ones, via the pyridinium salt intermediates.

Effect of iron content on selectivity in isomerization of α-pinene oxide to campholenic aldehyde over Fe-MMM-2 and Fe-VSB-5

Isomerization of α-pinene oxide to campholenic aldehyde (CA) was investigated over Fe-containing mesoporous mesophase materials (Fe-MMM-2) and microporous nickel phosphate molecular sieves (Fe-VSB-5). Activity and selectivity of reaction towards CA over Fe-containing materials was found to depend on iron content in materials that affects oligomeric state of Fe and amount of Lewis acid sites. In the presence of Fe-VSB-5 selectivity towards CA increased with increase in iron content in structure, while that decreased in the presence of Fe-MMM-2. This phenomenon is related to change in agglomeration of iron species in Fe-MMM-2 structure. The high selectivity towards CA in the presence of Fe-VSB-5 was suggested to arise from unique structure of these materials, which favours shape selectivity.

Cu/Ni-Catalyzed Cyanomethylation of Alkenes with Acetonitrile for the Synthesis of β,γ-Unsaturated Nitriles

We have developed a protocol for the Cu/Ni-catalyzed cyanomethylation of alkenes with acetonitrile for the synthesis of β,γ-unsaturated nitriles. This is the first example of a direct coupling of the alkene sp2 C - H bond and the acetonitrile sp3 C - H bond for the preparation of β,γ-unsaturated nitriles. Acetonitrile, an inexpensive and stable solvent, is demonstrated to be a useful cyanomethyl source. The combination of copper and nickel catalysts resulted in a high reaction efficiency.

Thermal and Photochemical Nitration of Aromatic Hydrocarbons with Nitrogen Dioxide

Aromatic hydrocarbons (ArH) are readily nitrated by nitrogen dioxide (NO2) in dichloromethane at room temperature and below (in the dark).The red colors, transiently observed, arise from the metastable precursor complex NO3(1-), which is formed in the prior disproportionation of nitrogen dioxide induced by the aromatic donor (eq 7).The deliberate irradiation of the diagnostic (red) charge-transfer absorption band (hνCT) of NO3(1-) at low temperatures results directly in aromatic nitration, even at -78 deg C, where the thermal nitration is too slow to complete.The mechanism of the photochemical (charge-transfer) nitration is established by time-resolved laser spectroscopy to proceed via the aromatic cation radical (ArH.+) formed spontaneously upon the charge-transfer excitation of NO3(1-) in Scheme 1.The related thermal activation of NO3(1-) derives from the adiabatic electron transfer that produces the same radical pair as the reactive intermediate in Scheme 3.The close relationship between the thermal/photochemical nitrations with nitrogen dioxide and those conventionally carried out with nitric acid (in the presence of nitrous acid) is delineated by Scheme 4.

The selective conversion of D-limonene to p,α-dimethylstyrene

Reaction conditions to facilitate the conversion of D-limonene selectively to p,α-dimethylstyrene (DMS) are described, in order to subsequently produce polymeric materials from biomass sourced from food waste. Limonene was dehydrogenated with several palladium catalysts and different solvents and bases, with copper chloride as oxidant at temperatures of 70-120 °C. Reaction conditions were identified using Pd(OAc)2 for the selective formation of only DMS from limonene in 2-5 hours, enabling the facile separation of DMS from unreacted starting material by vacuum distillation.

Desaturation of alkylbenzenes by cytochrome P450BM3 (CYP102A1)

A study was conducted to investigate the desaturation of alkylbenezenes by cytochrome P450BM3 (CYP102A1). It was observed during the study that oxidation of alkylbenzenes with CYP102A1 involves a gamut of P450 activity types that are terminal, sub-terminal benzylic and aromatic hydroxylation; terminal and sub-terminal desaturation; and epoxidation of the olefins. It was also found that the desaturation of cumene by CYP102A1 is sensitive to α-deuteration and insensitive to β-deuteration. Intramolecular deuterium isotope study revealed that the first abstraction in the desaturation of valproic acid and ezlopitant by microsomal P450s take place from activated carbon atoms. The increased β-hydroxylation percentages show that the β-carbon lies closer to the ferryl oxygen in the KT5.

The Convenient Way for Obtaining Geranial by Acid-Catalyzed Kinetic Resolution of Citral

A new simple method has been developed for isolation of geranial from citral, which is a mixture of two isomeric aldehydes, geranial and neral. The storage of citral in the presence of K10 montmorillonite clay has been demonstrated to result in an almost complete conversion of neral to dimeric and oligomeric products, with most geranial remaining unconverted. This enables isolation of geranial with the yield of up to 94%, based on the amount of geranial originally present in citral.

Investigations into the mechanism of action of nitrobenzene as a mild dehydrogenating agent under acid-catalysed conditions

Protonated nitrobenzene can be used to dehydrogenate a range of hydrocarbons, which already possess at least one double bond. Kinetic and spectroscopic results, together with known electrode potentials, yield approximate limits within which protonated nitrobenzenes can be expected to effect dehydrogenation of hydroaromatic compounds. A high yielding synthesis of benzo[j]fluoranthene is described.