Name | 1H-indazol-6-ol |
Synonyms | 6-Indazolol indazol-6-ol 1H-indazol-6-ol 6-hydroxyindazole 6-Hydroxyindazole 6-Hydroxy-1H-indazoL 6-Hydroxy-1H-indazole 1,2-dihydroindazol-6-one 1,2-dihydro-6H-indazol-6-one |
CAS | 23244-88-4 |
EINECS | 245-519-5 |
InChI | InChI=1/C7H6N2O/c10-6-2-1-5-4-8-9-7(5)3-6/h1-4,10H,(H,8,9) |
InChIKey | NUYZVDBIVNOTSC-UHFFFAOYSA-N |
Molecular Formula | C7H6N2O |
Molar Mass | 134.14 |
Density | 1.434±0.06 g/cm3(Predicted) |
Melting Point | 217.0 to 221.0 °C |
Boling Point | 366.5±15.0 °C(Predicted) |
Flash Point | 175.464°C |
Vapor Presure | 0mmHg at 25°C |
Appearance | Crystalline powder |
pKa | 9.17±0.40(Predicted) |
Storage Condition | Inert atmosphere,Room Temperature |
Refractive Index | 1.76 |
MDL | MFCD00022788 |
Physical and Chemical Properties | Light brown solid |
Hazard Symbols | Xn - Harmful |
Risk Codes | 22 - Harmful if swallowed |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36 - Wear suitable protective clothing. |
WGK Germany | 3 |
RTECS | NK8010000 |
use | 6-hydroxyindazole is a light brown powder, is an important pharmaceutical intermediate, used to construct the nucleus of active drugs, and has broad application prospects in the synthesis and screening of small molecule chemical drugs. 6-Hydroxyindazole has a neuroprotective effect. Indazole and its derivatives have a variety of biological activities, such as anti-inflammatory, anti-tumor, antioxidant, hypoglycemic, anti-HIV, anti-tuberculosis, anti-platelet, 5-HT3 receptor antagonism. In addition, indazole derivatives are also widely used in herbicides, dyes, etc. Indazole was first defined as "pyrazole ring and benzene ring", which belongs to the azole family and contains only three elements of carbon, hydrogen and oxygen. It is an aromatic heterocyclic ring containing 10 electrons. Theoretically, according to whether there are hydrogen atoms on the two nitrogen atoms, indazole has two tautomeric forms, namely 1H-indazole and 2H-indazole. When there is no substituent on indazole, it mainly exists in the form of 1H-indazole. |
preparation | indazole compounds are mainly synthesized by using o-halophenyl carbonyl compounds as raw materials to generate phenylhydrazine (or phenylhydrazone) and then intramolecular cyclization, diazotization reaction of o-methylaniline compounds, diazotization reaction of indigo, diazotization reaction of indole, etc. However, the above synthesis methods have low yields and complex post-treatment, which are not suitable for mass production of indazole. 6-Hydroxyindazole can be prepared from 6-aminoindazole by diazotization and then acidic hydrolysis to produce phenolic hydroxyl groups. The synthesis reaction formula is as follows: Figure 16-Hydroxyindazole Synthesis Reaction Formula 2-methyl -5-hydroxyaniline (2)40.0g(262.8mmol) is added to 400mL glacial acetic acid, stirred at 50 ℃ until dissolved, 36.3g(525.6mmol) of sodium nitrite is slowly added in batches, and reacted at 50 ℃ for 3 hours. Steam the solvent under reduced pressure, add 200mL of cold water, stir for 3 hours, adjust the pH value to about 8 with anhydrous potassium carbonate, filter, and dry to obtain 6-hydroxyindazole. NaNO2(63.9g,0.9259mol) was dissolved in 2.3L of water, and concentrated hydrochloric acid was added dropwise to pH 2~3 at room temperature. Then slowly drip the tetrahydrofuran solution of 6-aminoindazole into the aqueous solution of NaNO2. After dropping, stir at room temperature for 30min, and filter to obtain 6-hydroxyindazole. |
chemical properties | light brown solid |