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| | 3-Bromo-5-hydroxypyridine Basic information |
| | 3-Bromo-5-hydroxypyridine Chemical Properties |
| Melting point | 166-170 °C | | Boiling point | 343.7±22.0 °C(Predicted) | | density | 1.788±0.06 g/cm3(Predicted) | | storage temp. | Inert atmosphere,Room Temperature | | solubility | DMSO (Slightly), Methanol (Slightly) | | form | Crystalline Powder | | pka | 8.37±0.10(Predicted) | | color | White to tan | | Water Solubility | Slightly soluble in water. Soluble in chloroform and ethyl acetate. | | InChI | InChI=1S/C5H4BrNO/c6-4-1-5(8)3-7-2-4/h1-3,8H | | InChIKey | VNYBIBSZZDAEOK-UHFFFAOYSA-N | | SMILES | C1=NC=C(Br)C=C1O | | CAS DataBase Reference | 74115-13-2(CAS DataBase Reference) |
| Hazard Codes | Xi,Xn | | Risk Statements | 36/37/38-22-20/21/22 | | Safety Statements | 26-36/37/39-37-36-22 | | WGK Germany | 3 | | HazardClass | IRRITANT | | HS Code | 29339900 | | Storage Class | 11 - Combustible Solids | | Hazard Classifications | Acute Tox. 4 Oral
Eye Irrit. 2
Skin Irrit. 2
STOT SE 3 |
| | 3-Bromo-5-hydroxypyridine Usage And Synthesis |
| Description | 3-bromo-5-hydroxypyridine is an important industrial raw material widely used in medicine, pesticides, dyes, and other industries. Since the pyridine ring has biological activity and plays an irreplaceable role in synthesising drugs that cannot be replaced by other groups or functional groups, it is a hot area in pharmaceutical research. The hydroxyl and bromine atoms in the structure of 3-bromo-5-hydroxypyridine have diverse chemical reactivity. The alcohol hydroxyl unit in its structure can undergo nucleophilic substitution reactions with common alkyl halides under alkaline conditions to obtain corresponding ether derivatives. | | Chemical Properties | Light yellow needles | | Uses | 5-Bromo-3-methoxypyridine was refluxed with 20 mL (57%) of hydrogen bromide for 24 hours. The reaction was quenched with saturated sodium bicarbonate solution and the base mixture was extracted with 3 × 50 mL of dichloromethane. The organic fractions were pooled, dried (magnesium sulfate), filtered, and evaporated to give a white solid (3 g, >95% purity) identified as 3-bromo-5-hydroxypyridine by thin layer chromatography.
| | Synthesis | General procedure for the synthesis of 3-bromo-5-hydroxypyridine from 3-bromo-5-methoxypyridine: A mixed solution of 3-bromo-5-methoxypyridine (3318.8 g, 0.1 mol), hydrobromic acid (80 mL, 48%), and glacial acetic acid (60 mL) was stirred and reacted at 120 °C overnight. Subsequently, hydrobromic acid (60 mL, 48%) was slowly added to replenish the solvent lost due to evaporation and the reaction continued to be stirred at 120 °C overnight. Upon completion of the reaction, the reaction mixture was cooled to room temperature and poured into ice water. The pH was adjusted to about 6 with 6N NaOH solution and then extracted with ethyl acetate (2 x 200 mL). The organic layers were combined and dried over anhydrous sodium sulfate and subsequently concentrated under vacuum. The crude product was stirred in dichloromethane (150 mL) and the precipitate was collected by filtration. Finally, the precipitate was washed with dichloromethane to afford 3-bromo-5-hydroxypyridine (34; 15.2 g, 87.4% yield) as a white solid. | | References | [1] Patent: US2005/234236, 2005, A1. Location in patent: Page/Page column 13-14
[2] Patent: US2004/198736, 2004, A1. Location in patent: Page/Page column 86
[3] Tetrahedron Letters, 2004, vol. 45, # 18, p. 3607 - 3610
[4] Tetrahedron, 2009, vol. 65, # 4, p. 757 - 764
[5] Patent: WO2006/86068, 2006, A1. Location in patent: Page/Page column 18; 1/6 |
| | 3-Bromo-5-hydroxypyridine Preparation Products And Raw materials |
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