Name | Cyclopentene |
Synonyms | NSC 5160 Cyclopenten Cyclopentene 1-Cyclopentene Cyclopentene, tech. CYCLOPENTENE, STAB. Cyclopentene [UN2246] [Flammable liquid] UN2246 |
CAS | 142-29-0 10016-46-3 |
EINECS | 205-532-9 |
InChI | InChI=1/C5H8/c1-2-4-5-3-1/h1-2H,3-5H2 |
InChIKey | LPIQUOYDBNQMRZ-UHFFFAOYSA-N |
Molecular Formula | C5H8 |
Molar Mass | 68.12 |
Density | 0.771g/mLat 25°C(lit.) |
Melting Point | −135°C(lit.) |
Boling Point | 44-46°C(lit.) |
Flash Point | <−30°F |
Water Solubility | immiscible |
Solubility | water: soluble0.535g/L at 25°C |
Vapor Presure | 20.89 psi ( 55 °C) |
Appearance | Liquid |
Specific Gravity | 0.771 |
Color | Colorless |
BRN | 635707 |
Storage Condition | 0-6°C |
Stability | Stable. Highly flammable. Incompatible with strong oxidizing agents. Store cold. |
Sensitive | Air Sensitive |
Refractive Index | n20/D 1.421(lit.) |
Physical and Chemical Properties | Characteristics of colorless, irritating gas. soluble in ethanol, ether, benzene and petroleum ether, insoluble in water. |
Use | Used as comonomer and also used in organic synthesis |
Risk Codes | R11 - Highly Flammable R21/22 - Harmful in contact with skin and if swallowed. R36/37/38 - Irritating to eyes, respiratory system and skin. R65 - Harmful: May cause lung damage if swallowed R67 - Vapors may cause drowsiness and dizziness R52/53 - Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment. R38 - Irritating to the skin |
Safety Description | S9 - Keep container in a well-ventilated place. S16 - Keep away from sources of ignition. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S33 - Take precautionary measures against static discharges. S36 - Wear suitable protective clothing. S62 - If swallowed, do not induce vomitting; seek medical advice immediately and show this container or label. S61 - Avoid release to the environment. Refer to special instructions / safety data sheets. S36/37 - Wear suitable protective clothing and gloves. |
UN IDs | UN 2246 3/PG 2 |
WGK Germany | 3 |
RTECS | GY5950000 |
FLUKA BRAND F CODES | 10-23 |
TSCA | Yes |
HS Code | 29021990 |
Hazard Class | 3 |
Packing Group | II |
Toxicity | Acute oral LD50 for rats is 1,656 mg/kg (quoted, RTECS, 1985). |
colorless, irritating liquid. Melting Point -135.076 °c. Boiling point 44.2 °c. The relative density was 0.772. Refractive index 4225. Flash point -50 °c. Liquid viscosity 0.2mPa.s(50 C). The surface tension was 16.0 mN/m. Ignition point 385 °c. Explosion limit (20 ℃,O.lMPa)3.4% ~ 8.5% (volume). The critical temperature is 233. The critical volume was 0.276 ml/g. The critical pressure is 4.64MPa. Soluble in ethanol, ether, benzene and petroleum ether, insoluble in water.
It is used in large quantities for the production of polycyclopentene rubber. It is also used for the preparation of cyclopentyl phenol (disinfectant), cyclic aldehyde, cyclopentyl glycol and so on.
Henry's Law Constant | 6.3 x 10-2 atm?m3/mol at 25 °C (Hine and Mookerjee, 1975) |
LogP | 2.47 at 25℃ |
NIST chemical information | information provided by: webbook.nist.gov (external link) |
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
Chemical reaction | cyclopentene contains double bond, chemical activity mainly occurs in the double bond, easy polymerization, formation of polypentene, is a rubber raw material; Catalytic hydrogenation, forming cyclopentane; Catalytic oxidation, forming cyclopentadiene; And cyclopentadiene can be carried out at 200 C di-a (Diels-Alder) reaction, forming 2, 3-dihydrobridged cyclodicyclopentadiene; Reaction with carbon tetrachloride at low temperature to produce 1, 2-dichlorocyclopentane; Carbonyl addition can be carried out under the action of catalyst at 120 ℃ and pressure, formyl cyclopentane (cyclopentyl formaldehyde) is formed; It absorbs oxygen and is oxidized when exposed to air for a long time; Glutaric acid can be prepared by reacting with potassium nitrate aqueous solution at 110 ℃ and 1.0MPa; in addition to the reactivity of the double bond, the hydrogen on the amyl ring may also be substituted, such as halogenation, alkylation, acylation, and the like. This information was edited by chemical book Xiaonan (2015-08-31). |
cyclopentadiene | cyclopentadiene is an alicyclic olefin with high chemical activity, which is a colorless liquid at room temperature, has a special odor. It contains active methylene, so it is easy to polymerize into dicyclopentadiene at room temperature. The physical properties of cyclopentadiene and dicyclopentadiene are quite different. (See table 1) both cyclopentadiene and dicyclopentadiene are easily oxidized to peroxides in the air, and both are easily reacted with unsaturated compounds to produce a dynes-Aldene synthesis reaction to form a six-member cyclic compound. Cyclopentadiene is polymerized with olive oil, tung oil, linseed oil and the like in a solvent, and the resulting polymer can be used to produce a film. The chlorides of cyclopentadiene are pesticides. Cyclopentadiene and transition metal salts, in Dimethyl Sulfoxide-ethylene glycol dimethyl ether alkaline solution reaction, the formation of ferrocene can be used as rocket fuel additives, rubber and silicone curing agents and UV absorbers. cyclopentadiene can be produced by bromination of pentene and dehydrobromination by heating in the presence of sodium acetate. During the refining of crude benzene in Coking Industry, the initial fraction obtained by preliminary distillation of light benzene contains cyclopentadiene, and its content is related to the properties of coal, coking temperature, the operating system of crude benzene recovery is related to the operating conditions of light benzene preliminary distillation and other factors, and the fluctuation range is 3 ~ 30%. The initial fraction also contains carbon disulfide, benzene, cycloalkanes, hydrogen sulfide, ketones, acetonitrile and other unsaturated compounds. Cyclopentadiene and carbon disulfide boiling point difference is only 3.8 deg C, and other olefins and alkanes boiling point is also very close to the distillation method is difficult to obtain high purity cyclopentadiene products. The initial fraction after pretreatment into the distillation kettle (see carbon disulfide), thermal polymerization under Total reflux operation conditions, cyclopentadiene polymerization into a boiling point of 170 deg C dicyclopentadiene after distillation, distillation of carbon disulfide products, after the middle distillate and benzene, the residue in the distillation kettle is a product containing 90-95% of dicyclopentadiene. The dicyclopentadiene is easily dissociated by heat to form cyclopentadiene. At lower temperatures, the rate of polymerization is greater than the rate of depolymerization, The temperature in the kettle should be appropriately controlled when carrying out the polymerization operation. The time required for the polymerization operation is not only related to the polymerization temperature, but also related to the turbulence degree of the material in the distillation kettle, the initial pressure in the kettle and the composition of the raw materials. Mitomycin name molecular weight molecular formula boiling point ℃ melting point ℃ density (20 ℃)g/mL refractive index cyclopentadiene C5H66642. 5-850.80741.4446(18.5 °c) dicyclopentadiene (35 °c) Table 1 shows the physical properties of cyclopentadiene and dicyclopentadiene. The components in the initial fraction are volatile, but also flammable, explosive, toxic, so the production workshop must be forced ventilation, fire prevention, Explosion Prevention, poisoning prevention and anti-static accumulation and other measures. During storage of the dicyclopentadiene product, a stabilizer, xylenol, should be added to prevent oxidation of the product. The product should be packed in tubes and stored in a storage room. The dicyclopentadiene is gasified, cracked, and cooled by condensation to obtain cyclopentadiene. Cyclopentadiene products need to be stored in a storage room below -12 ℃. |
Use | for the production of polycyclopentene rubber, cyclopentanediol -1,2-and cyclopentene oxide, drug ketamine, cyclopentyl phenol (disinfectant), cyclic aldehyde, cyclopentyl glycol, etc. for the production of bromocyclopentane, etc. for the production of various chemical raw materials for organic synthesis, as a crosslinking agent for resin; Gas chromatography comparison samples. used as comonomer and also used in organic synthesis |
production method | 1. Cyclopentanol was first prepared by gas phase dehydration using alumina as a catalyst at 380-400 °c. 2.BASF-Erd? The chemie method takes C5 fraction, a by-product of petroleum cracking, as a raw material, and makes cyclopentadiene dimerization into dicyclopentadiene by heating, which is extracted with N-methyl pyrrolidone, cyclopentene and isoprene are obtained by selective hydrogenation to cyclopentene and then added to the material containing cyclopentadiene, followed by extraction, distillation and fractionation. 3.Bayer method C5 fraction was heat-treated to obtain dicyclopentadiene, which was then depolymerized into cyclopentadiene. Finally, the catalytic hydrogenation of cyclopentene. A palladium-based catalyst was used with Cr or Ti as a cocatalyst and Li-Al spinel as a support. IFP method for the French Institute of Petroleum Chemistry developed catalyst for the above operation of the preparation of cyclopentene method. The catalyst consisted of Cd2Ti-(OC6H5)2 and Li(t-BuO)3AlH with a conversion of 99.99% and a selectivity of 97%. |
category | flammable liquid |
toxicity grade | poisoning |
Acute toxicity | oral-rat LD50: 1656 mg/kg |
explosive hazard characteristics | explosive when mixed with air |
flammability hazard characteristics | in case of open flame, high temperature, flammable oxidant; Combustion stimulus smoke |
storage and transportation characteristics | The warehouse is ventilated and dried at low temperature; It is stored separately from oxidants and acids; It is not suitable for long storage, to prevent aggregation |
extinguishing agent | dry powder, dry sand, carbon dioxide, foam, 1211 extinguishing agent |
autoignition temperature | 743 ° F. |