Preparation and application background and overview of 2-hydroxy-5-iodopyridine
2-Hydroxy-5-iodopyridine is an organic intermediate that can be prepared from 2-aminopyridine in two steps. It has been reported in the literature that 2-hydroxy-5-iodopyridine can be used to prepare a modified corncob adsorbent for the adsorption and removal of kanamycin.
Preparation and application of 2-hydroxy-5-iodopyridine
A mixture of 2-aminopyridine (3.8 g, 0.4 mmol), periodic acid dihydrate (1.83 g, 8 mmol) and iodine (4.08 g, 4 mmol) was dissolved in acetic acid (24 mL), water (4.8 mL) and sulfuric acid (0.79 mL) and heated at 80°C for 4 h. The reaction mixture was then poured into a 10% Na2S2O3 aqueous solution, followed by extraction with diethyl ether. The extract was washed with 10% aqueous sodium hydroxide solution and water, dried (Na2SO4), and concentrated in vacuo with heavy calcium carbonate. The residue was purified by silica gel column chromatography (5% methanol/chloroform) to give 5.19 g of 2-amino-5-iodopyridine (59%). 1H NMR (CD3OD) δ 6.34 (d, 1H), 7.57 (d, 1H) 8.03 (s,1H); HRMS (FAB) calcd for C5H4NOI + H+ 221.9416,found 221.9416.
Dissolve 2-amino-5-iodopyridine (2.36 g, 10.7 mmol) in concentrated sulfuric acid (72 mL) while stirring in an ice bath. Add sodium nitrite (0.30 g, 10.7 mmol) while stirring in an ice bath. ). This was stirred at 60 °C for 30 min and cooled to room temperature. Boric acid (0.53 g, 21.4 mmol) was added to the reaction mixture, and the mixture was rapidly heated to 100 °C with heavy calcium carbonate and cooled to ambient temperature. Neutralize the mixture by adding ammonium hydroxide while cooling in an ice bath. After rotary evaporation of the solvent in vacuo, the product was extracted with hot methanol. Purification by silica gel column chromatography (5% methanol/chloroform) gave the pure product 2-hydroxy-5-iodopyridine (2.21 g, 94%). 1H NMR (DMSO-d6) δ 6.22 (d,1H), 7.57 (d, 1H), 7.65 (s, 1H); HRMS (FAB) calcd for C5H4-NOI + H+ 221.9416, found 221.9416.
Preparation and application of 2-hydroxy-5-iodopyridine
CN201710330001.6 discloses a modified corncob adsorbent for adsorption and removal of kanamycin. Select corn cobs with a particle size of 4 to 6 mm, wash with deionized water, absolute ethanol, and NaOH solution and dry to obtain substance Q; substance Q is passed through 2-fluoro-4-methyl-5-bromopyridine, 2-hydroxyl – A mixture of 5-iodopyridine, 2-chloro-3-methylthiophene, chromone-3-carbaldehyde, benzylideneacetone, pyrazole anthrone and dipentylbenzoquinone was modified to prepare substance R. ; The substance R obtained after being modified by a mixture prepared by cesium iodide, manganese sulfate, sulfur hexafluoride, nickel fluoride, hydroxylamine hydrochloride, hydrazine sulfate and potassium fluoride is used for adsorption and removal of kanamycin. Modified corncob adsorbent.
References
[1] Bevers S , Ha S B , Mclaughlin L W . Critical nature of a specific uridine O2-carbonyl for cleavage by the hammerhead ribozyme[J]. Biochemistry, 1999, 38(24):7710.
[2] [Invented in China] CN201710330001.6 Modified corncob adsorbent for adsorption and removal of kanamycin
