Name | Imidazole |
Synonyms | IMZ IMIDAZOLE GLYOXALIN IMINAZOLE Imidazole Glyoxaline 1,3-diazole 1,3-DIAZOLE 1H-IMIDAZOLE 1H-imidazole IMIDAZOLE BUFFER Imidazole Glyoxaline LABOTEST-BB LTBB001344 Imidazole, ULTROL Grade 1,3-DIAZA-2,4-CYCLOPENTADIENE |
CAS | 288-32-4 |
EINECS | 206-019-2 |
InChI | InChI=1/C3H4N2/c1-2-5-3-4-1/h1-3H,(H,4,5) |
InChIKey | RAXXELZNTBOGNW-UHFFFAOYSA-N |
Molecular Formula | C3H4N2 |
Molar Mass | 68.08 |
Density | 1.01g/mLat 20°C |
Melting Point | 88-91°C(lit.) |
Boling Point | 256°C(lit.) |
Flash Point | 293°F |
Water Solubility | 633 g/L (20 ºC) |
Solubility | H2O: 0.1M at20°C, clear, colorless |
Vapor Presure | <1 mm Hg ( 20 °C) |
Appearance | White Crystals |
Specific Gravity | 1.03 |
Color | white |
Odor | Amine like |
Maximum wavelength(λmax) | ['λ: 260 nm Amax: 0.10', , 'λ: 280 nm Amax: 0.10'] |
Merck | 14,4912 |
BRN | 103853 |
pKa | 6.953(at 25℃) |
PH | 9.5-11.0 (25℃, 50mg/mL in H2O) |
Storage Condition | Store below +30°C. |
Stability | Stable. Incompatible with acids, strong oxidizing agents. Protect from moisture. |
Sensitive | Hygroscopic |
Refractive Index | 1.4801 |
MDL | MFCD00005183 |
Physical and Chemical Properties | Characteristics of colorless prismatic crystals, weakly alkaline. melting point 90~91 ℃ boiling point 257 ℃ relative density 1.0303 refractive index 1.4801 flash point 145 ℃ solubility, ethanol, ether, chloroform, pyridine, benzene-soluble, insoluble in petroleum ether. |
Use | Used as raw materials and intermediates in organic synthesis for the preparation of drugs and pesticides |
Risk Codes | R36/38 - Irritating to eyes and skin. R63 - Possible risk of harm to the unborn child R34 - Causes burns R22 - Harmful if swallowed R20/21/22 - Harmful by inhalation, in contact with skin and if swallowed. R61 - May cause harm to the unborn child |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) S22 - Do not breathe dust. S36 - Wear suitable protective clothing. S27 - Take off immediately all contaminated clothing. S53 - Avoid exposure - obtain special instructions before use. |
UN IDs | UN 2923 8/PG 3 |
WGK Germany | 1 |
RTECS | NI3325000 |
TSCA | Yes |
HS Code | 29332990 |
Hazard Class | 8 |
Packing Group | III |
Toxicity | LD50 in mice (mg/kg): 610 i.p.; 1880 orally (Nishie) |
Raw Materials | Ammonium hydroxide Formaldehyde Glyoxal |
Downstream Products | clotrimazole crystalline Miconazole nitrate Econazole |
Reference Show more | 1. Gao Jing, Wang Nan, Guan Sijing, etc. Study on the signal mechanism of stomatal closure induced by Beauveria bassiana [J]. Shaanxi Agricultural Sciences, 2019, 065(005):72-75. 2. He, Tong, et al. "Dummy molecully imaged polymer-based microplate chemistry sensor for one-step detection of gross dies in egg." Food chemistry 288 (2019): 347-353.https:// doi.org/10.1016/j. Food Chem. 3/031, 2019 3. Jiang, Zu Qiang, et al. "Determination of Tetracyclines in Milk with a Molecularly Imprinted Polymer-Based Microtiter Chemiluminescence Sensor." Analytical Letters 52.8 (2019): 1315-1327.https://doi.org/10.1080/00032719.2018.1537282 4. Che, Haoqi, et al. "Exopolysaccharide from Streptococcus thermophilus as stabilizer in fermented dairy: Binding kinetics and interactions with casein of milk." International journal of biological macromolecules 140 (2019): 1018-1025.https://doi.org/10.1016 5. [IF=7.514] Tong He et al."Dummy molecularly imprinted polymer based microplate chemiluminescence sensor for one-step detection of Sudan dyes in egg."Food Chem. 2019 Aug;288:347 6. [IF=2.329] Zu Qiang Jiang et al."Determination of Tetracyclines in Milk with a Molecularly Imprinted Polymer-Based Microtiter Chemiluminescence Sensor."Anal Lett. 2019;52(8):1315-1327 7. [IF=2.329] Ming Xin Xu et al."Determination of β-Agonists in Porcine Urine by Molecularly Imprinted Polymer Based Chemiluminescence."Anal Lett. 2019;52(11):1771-1787 8. [IF=1.321] Xin-Ying Zhang et al."Molecularly Imprinted Polymer Based Chemiluminescence Method for Detection of Nitrofurans."Aust J Chem. 2019 Feb;72(5):375-382 9. [IF=5.909] Liwei Sun et al."Bi-functionalized ionic liquid-grafted mesoporous alumina: Synthesis, characterization and CO2/N2 selectivity."J Environ Chem Eng. 2021 Oct;9:105829 |
colorless rhombic crystals. Melting point 90-91 °c. Boiling point 257 ℃,165~168 ℃ (2.7kPa),138.2 ℃(1.6kPa). The relative density of 1.0303(101 deg C). Refractive index 1.4801 (101 degrees C). Flash point 145 °c. Soluble in water, ethanol, ether, chloroform, pyridine, benzene-soluble, very slightly soluble in petroleum ether. Weakly alkaline. With the high manganese acid aqueous solution to produce formic acid; And hydrogen peroxide to generate oxalic acid.
This product has the following two synthetic routes.
This product is mainly used as a curing agent for epoxy resin, and its dosage is 0.5% ~ 10% of epoxy resin. Imidazole is one of the main raw materials for producing anti-fungal drugs such as diclofenac, econazole, ketoconazole and clotrimazole. From imidazole and 2, 4-chloroacetophenone as the main raw material can be prepared by imazole, is an antifungal drug, is also widely used as fruit preservatives.
pH indicator color change ph range | 9.5 - 11 |
LogP | -0.02 at 25℃ |
NIST chemical information | Information provided by: webbook.nist.gov (external link) |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
Physical properties | Only imidazole derivatives exist in nature, but no free imidazole. Those precipitated from benzene are monoclinic prismatic colorless crystals. It smells of ammonia. Relative molecular mass 68.08. Relative density 1.0303(101/4 ℃). Melting point 89~91 ℃, boiling point 257 ℃, 165 ℃ ~ 168 ℃(2.67 × 103Pa), 138.2 ℃(1.60 × 103Pa). Flash point 145 ℃. The refractive index 1.4801(101 ℃). Viscosity 2.696mPa · s(100 ℃). Slightly soluble in benzene, petroleum ether, soluble in ether, acetone, chloroform, pyridine, soluble in water (room temperature 70), ethanol. Weak alkaline. Because the hydrogen bond is formed between the-NH-bond in position 1 and the-N = bond in position 3, the boiling point is higher. When the hydrogen in position 1 is replaced, the hydrogen bond cannot be formed and the boiling point drops. It is stable to heat and hardly decomposes below 250 ℃ (decomposition temperature 590 ℃). It is also stable to reducing agents and oxidants, but can form stable salts with inorganic acids. It has certain aromatic properties and can be halogenated, nitrated, sulfonated and hydroxymethylated under the action of a catalyst. And can be coupled with diazonium salt in position 2. In addition, since the = NH group (1 position) connects two double bonds and is somewhat "acidic", it can be replaced by a metal to form a salt. The 3-position nitrogen has coordination effect on metal ions and can form chelates. Although it is difficult to be reduced, it can be added with protons to form a cationic and resonant structure to form a stable form. The tautomers of the imidazole ring are easy to change, so the isomers at position 4 and 5 are not easy to distinguish. |
main uses | imidazole is slightly more basic than pyrazole and can generate stable salts, such as picric acid salt and nitrate. One use of imidazole is in metal chelation affinity chromatography (IMAC) for the purification of His-tagged proteins. The tag protein combines with the nickel ion medium in the bead holes on the surface of the chromatography column, and the excess imidazole passes through the chromatography column to elute the tag protein coordinated with nickel to obtain a high-purity target protein. Imidazole is an important fine chemical raw material, mainly used in the synthesis of medicine and pesticides and epoxy resin curing agent, used as pesticide raw material, synergist for boric acid preparation, preparation of insecticides and fungicides. Used as epoxy resin curing agent, it can improve the mechanical properties of products such as bending, stretching, compression, etc., improve the electrical properties of insulation, and improve the chemical properties of chemical resistance. It is widely used in computers and electrical appliances. It is used in medicine for imidazole antifungal drugs. It is one of the main raw materials of drugs such as bischlorobendazole, econazole, ketoconazole, clotrimazole, etc. It can be used as copper rust inhibitor for printed circuit plates and integrated circuits. It is also used as raw materials and organic synthetic intermediates for urea-formaldehyde resin curing agents, photographic drugs, adhesives, coatings, rubber vulcanizing agents, antistatic agents, etc., and is also widely used as preservatives for fruits. |
preparation method | using glyoxal as raw material, reacting with ammonium sulfate (or ammonia) in formaldehyde at 85~90 ℃, the sulfate of imidazole is first prepared, and then neutralized with calcium hydroxide to obtain crude imidazole products, filtration, washing with water, combining filtrate and washing liquid, evaporation and concentration under reduced pressure, crystallization, and can be prepared. If ammonia is used directly, the treatment step without sulfate can be made in one step. Whether ammonium sulfate or ammonia is used, the yield of this method is relatively low, about 45%. Using o-phenylenediamine and formic acid as raw materials, cyclize to generate benzimidazole, which is then oxidized in sulfuric acid solution to generate dicarboxylic imidazole, and finally under the action of copper oxide, decarboxylation at 100~150 ℃ can produce crude products, and then recrystallize in benzene solution to obtain imidazole products. using D-tartaric acid as raw material, nitration with nitric acid in sulfuric acid to prepare 2, 3-dinitrotaric acid, and then react with ammonia in formaldehyde to prepare dicarboxyimidazole, and then decarboxylate to prepare. |
use | imidazole is an intermediate of pesticides such as imidazole and prochloraz, and is also an intermediate of pharmaceutical antifungal drugs such as diclofenimazole, econazole, ketoconazole and clotrimazole. used as raw materials and intermediates for organic synthesis, used to prepare drugs and pesticides used as analytical reagents, also used in organic synthesis imidazole can be used as epoxy resin curing agent, can improve the bending of products, tensile, compression and other mechanical properties, improve the electrical properties of insulation, improve the chemical properties of chemical resistance, widely used in computers, electrical appliances; as a copper rust inhibitor, it is used in printed circuit boards and integrated circuits; used as a pharmaceutical raw material for the manufacture of antifungal drugs, antifungal agents, hypoglycemia treatment drugs, artificial plasma, trichomoniasis treatment drugs, bronchial asthma treatment drugs, Anti-rash agents, etc.; used as raw materials for pesticides, synergists for boric acid preparations, insecticides and fungicides; in addition, imidazole is also used as a raw material for urea-formaldehyde resin curing agent, photographic medicine, adhesive, coating, rubber vulcanizing agent, antistatic agent, etc.; organic synthesis intermediate. pesticide intermediate: fungicide intermediate: triazole fungicide as an intermediate in the pharmaceutical industry, it is used to prepare antifungal drugs such as clotrimazole, miconazole, econazole, ketoconazole, etc. Used as curing agent for epoxy resin; Used as imidazole derivative glymarcin, carbonyl diimidazole and other raw materials; Effective buffer in pH 6.2-7.8 range; Used for titration of aspartic acid and glutamic acid determination of zinc brightener cobalt. Organic synthesis. Used for anti-metabolism and anti-histamine. The pH value is in the range of 6.2-7.8 and can be used as a buffer. Titration of aspartic acid and glutamic acid Imidazoles are mainly used as curing agents for epoxy resins, accounting for less than half of the consumption of imidazoles in Japan, and their dosage is 0.5%-10% of epoxy resins. Imidazole compounds can be used as antifungal drugs, antifungal agents, hypoglycemia therapeutic drugs, artificial plasma, etc., can also be used as treatments, artificial plasma, etc., and can also be used as drugs for the treatment of trichomoniasis and turkey blackhead. Imidazole is one of the main raw materials in the production of imidazole antifungal drugs, diclofenazole, econazole, ketoconazole and clotrimazole. From imidazole and 2,4,ω-trichloroacetophenone as the main raw materials, the fruit fungicide imaizole can be prepared. Add 2,4,ω-trichloroacetophenone to anhydrous methanol, heat and reflux, and add bromine dropwise. After the color of the solution gradually disappears, cool to 0 ℃, add imidazole and stir intensively for 3 hours. Then steam the methanol under reduced pressure. The remaining liquid is poured into water and extracted with dichloromethane. After the extraction liquid recovers dichloromethane, dilute nitric acid is added to form a salt. After recrystallization with water, ammonia treatment is used to obtain 2 ',4'-dichloro-2-imidazole acetophenone. Further use sodium borohydride to reduce to the corresponding alcohol, and finally in the presence of sodium hydroxide and dimethylformamide, allyl chloride is used to prepare Imezole (Enilconazde, also known as enconazole). The structure and production methods of imazole and diclofenazole (miconazole) have some similarities. Bischlorobenzimidazole is a broad-spectrum fungal drug. Imezole is also an antifungal drug, but it is widely used as a preservative for fruits (also known as Imazalil). |
production method | is obtained by cycliping and neutralizing glyoxal. Put glyoxal, formaldehyde and ammonium sulfate into the reaction pot, stir and heat to 85-88 ℃, and keep the temperature for 4 hours. Cold to 50-60 ℃, neutralize with lime water to pH above 10. Heat to 85-90 ℃, exhaust ammonia for more than 1h, cool slightly, filter, wash the filter cake with hot water, combine washing and filtrate, concentrate under reduced pressure until anhydrous steaming, continue to distill under reduced pressure until all low boiling materials are steamed, collect 105-160 ℃(0.133-0.267kPa) fraction, and obtain imidazole. The yield is about 45%. Another method is to cyclize o-phenylenediamine and formic acid to form benzimidazole, and then react with hydrogen peroxide to open the ring to 4,5-dihydroxyimidazole, and finally decarboxylate to obtain imidazole. 4, 5-dihydroxyimidazole can also be obtained by nitration and cyclization of d-tartaric acid. The process of decarboxylation of 4, 5-dicarboxyimidazole to prepare imidazole is as follows: 4, 5-dihydroxyimidazole is mixed with copper oxide, heated to 100-280 ℃, a large amount of carbon dioxide gas is released, and the distillate is collected. The crude product is obtained, and the finished product is recrystallized with benzene, and the yield is 76%. the preparation method is to put glyoxal, formaldehyde and ammonium sulfate into a reaction pot, stir and heat to 85-88 ℃, keep the temperature for 4 hours, cool to 50-60 ℃, neutralize with lime water to pH = 10 or more, heat to 85-90 ℃, discharge ammonia for more than 1 hour, cool slightly, filter, wash the filter cake with hot water, combine the washing filtrate, and concentrate under reduced pressure until steaming without water, continue to distill until all the low boiling materials are evaporated, and collect 105~160 ℃/133 ~ 266Pa fraction to obtain imidazole. O-phenylenediamine can also be used as raw material, added to formic acid, stirred and heated, kept at 95~98 ℃ for 2h, cooled to 50~60 ℃, adjusted to pH = 10 with 10% NaOH, reduced to room temperature, filtered and washed with water, dried to obtain benzimidazole. Benzimidazole is added into concentrated sulfuric acid under stirring, the temperature is raised to 100 ℃, and H2O2 is slowly dropped. After addition, stir and react at 140~150 ℃ for 1h, cool to 40 ℃, dilute with water, precipitate crystallization, filter, wash with water, and dry to obtain 4, 5-dicarboxyimidazole. 4, 5-dicarboxyimidazole is mixed with copper oxide, heated to 100~280 ℃, a large amount of carbon dioxide gas is released, and the distillate is collected to obtain crude white lumps and recrystallized with benzene to obtain fine imidazole. |
spontaneous combustion temperature | 480°C |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |