aziridine
aziridine - Names and Identifiers
| Name | aziridine |
| Synonyms | Azirane aziridine Aziridina ethenimine Ethyleneimine AZIRIDINEHARDENER dihydro-1h-azirin Ethylenimine, monomer Aziridine(ethylenimine) Ethylen(e)imine,monomer aziridine(ethyleneimine) Aziridine (Ethyleneimine) AZIRIDINE (ETHYLENEIMINE), STABILIZED WITH NAOH |
| CAS | 151-56-4 |
| EINECS | 205-793-9 |
| InChI | InChI=1/C2H3N/c1-2-3/h3H,1H2 |
aziridine - Physico-chemical Properties
| Molecular Formula | C2H5N |
| Molar Mass | 43.07 |
| Density | 0,83 g/cm3 |
| Melting Point | -78°C |
| Boling Point | 56°C |
| Flash Point | -11°C |
| Water Solubility | miscible |
| Solubility | miscible with water and virtually all organic solvents |
| Vapor Presure | 160 at 20 °C, 250 at 30 °C (quoted, Verschueren, 1983) |
| Appearance | Colorless liquid |
| Odor | Fishy; ammoniacal. |
| Exposure Limit | TLV-TWA (skin) 0.5 ppm (～1 mg/m3)(ACGIH, OSHA, and MSHA); Poten tial Human Carcinogen in the workplace(OSHA), Potential Carcinogen (NIOSH). |
| pKa | 8.01(at 25℃) |
| Stability | Highly flammable. Reacts with a wide variety of materials. |
| Refractive Index | nD25 1.412 |
| Physical and Chemical Properties | Cycloethylamine pure colorless liquid, ammonia odor, freezing point -74 ℃, B. p. 55~56 ℃,n25D 1.4123, relative density 0.832(24 ℃),f. P. 12 ℃, can be miscible with water, soluble in ethanol, aqueous solution is alkaline, when acid or absorption of carbon dioxide easy polymerization, commodity cycloethylamine contains a small amount of sodium hydroxide as stabilizer. |
| Use | For organic synthesis, and used as a binder, mutagen, in the electroplating industry for the production of new brighteners |
aziridine - Reference Information
| Henry's Law Constant | 1.33(x 10-7 atm?m3/mol) at 25 °C (quoted, Mercer et al., 1990) |
| LogP | -2.68--0.28 at 25℃ |
| (IARC) carcinogen classification | 2B (Vol. 9, Sup 7, 71) 1999 |
| NIST chemical information | Information provided by: webbook.nist.gov (external link) |
| EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
| Uses | Cycloethylamine, also known as aziridine, aziridine, and ethyleneimine, is an intermediate for the preparation of the carbamate insecticide dioxyl. In the synthesis of pesticides and medicines, cycloethylamine is a very useful aminoethyl agent. Ethyleneimine is an intermediate of fine chemicals. The condensation of ethyleneimine and phosphorus sulfide chloride can yield thiotepian. Ethyleneimine is first condensed with tetrachlorobenzoquinone and then with potassium methoxyethanol to obtain imidoquinone. Both tietipa and imidoquinone are anti-malignant drugs. |
| Production method | (1) It is obtained by esterifying ethanolamine with sulfuric acid, and then cyclizing with sodium hydroxide. Ethanolamine and water are added to the reaction pot, 98% sulfuric acid is gradually added dropwise, the temperature is controlled at 10-30 ℃, the temperature is kept warm and stirred for 30min, then the temperature is raised to 50 ℃, vacuum dehydration is carried out, and the reaction is finished when the reactants are white crystals at 180 ℃. The esterified substance is causticized with 30% sodium hydroxide, and aziridine is steamed out at 100 ℃ to obtain the finished product. (2) 2-chloroethylamine method: 2-chloroethylamine or its hydrochloride reacts with 30% sodium hydroxide aqueous solution at 60-70 ℃, the reaction product is distilled at 35 ℃, and aziridine aqueous solution is distilled, containing aziridine 71.6%. (3) dichloroethane method: using dichloroethane as raw material, in the presence of HCl receptor or co-catalyst and ammonia. (4) gas phase dehydration method: the next step of catalytic dehydration of ethanol under high temperature and gas phase conditions:(5) ethylene oxide method: there are mainly 4 preparation methods of cycloethylamine. The sulfation method is obtained by first esterification of ethanolamine and sulfation, and then cyclization of sodium hydroxide. NH2CH2CH2OH + H2SO4 → NH2CH2CH2OSO3H Add 30kg of ethanolamine (100%) and 25kg of water into the reaction pot, slowly drop 50kg 98% of sulfuric acid under stirring, and control the temperature at 10~30 ℃; After addition, keep warm and stir for 0.5h, then heat to 50 ℃, dehydrate under reduced pressure, and end when the reactants are white crystals at 7.99kPa and 148 ℃. It can also be dehydrated until micro-crystallized, cooled and crystallized, filtered, washed with a small amount of water, filtered, and dried to prepare ammonia ethanol hydrogen sulfate. The ammonia ethanol hydrogen sulfate is put into the sodium hydroxide solution of the 200kg 30%, the temperature is heated to 100 ℃, and cycloethylamine and water are distilled to obtain 125kg of distillate (content 9% ~ 10%). Another operation method is to cool the distillate in an ice bath, add solid sodium hydroxide for dehydration, and let it stand for stratification; take the oil layer and then dehydrate with potassium hydroxide, rectify, collect the 55~75 ℃ fraction to obtain Cycloethylamine, based on ethanolamine, the yield is 45%. Dichloroethane method is obtained by interacting with ammonia in the presence of hydrogen chloride acceptor or cocatalyst. The above reaction was carried out in the presence of calcium oxide, the reaction temperature was 100 ℃, and the yield was about 60%. This method is a newly developed method, and the yield is higher than that of ethanolamine gas phase dehydration. 2-chloroethylamine method 2-chloroethylamine or its hydrochloride is obtained by reacting with sodium hydroxide (30% aqueous solution) at 60~70 ℃. Ethanolamine gas phase dehydration is obtained by catalytic dehydration under high temperature and gas phase conditions. The preparation of cycloethylamine by gas phase dehydration from ethanolamine is the simplest method, but industrialization has not yet been realized due to the unsatisfactory conversion and selectivity. |
| category | toxic substances |
| toxicity classification | highly toxic |
| acute toxicity | oral administration-rat LD50:15 mg/kg; Inhalation-mouse LC50:400 mg/m3/2 h |
| stimulation data | skin-rabbit 10 mg/24 hours moderate; Eye-rabbit 2 mg severe |
| explosive hazard characteristics | blastable when mixed with air; aggregate blastable |
| flammability hazard characteristics | flammable in case of open flame, high temperature and oxidant; toxic nitrogen oxide smoke from combustion |
| storage and transportation characteristics | warehouse ventilation and low temperature drying; Store separately from oxidants and acids |
| fire extinguishing agent | dry powder, dry stone powder, carbon dioxide, foam |
| occupational standard | TWA 1 mg/m3; STEL 3 mg/m3 |
| toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |
| immediate life-threatening and health concentration | 100 ppm |
Last Update：2024-04-09 02:00:07
