3-BROMO-PYRAZOLO[1,5-A]PYRIDINE synthesis
- Product Name:3-BROMO-PYRAZOLO[1,5-A]PYRIDINE
- CAS Number:5910-12-3
- Molecular formula:C7H5BrN2
- Molecular Weight:197.03
![Pyrazolo[1,5-a]pyridine-3-carboxylic acid](/CAS/GIF/16205-46-2.gif)
16205-46-2
5910-12-3
The general procedure for the synthesis of 3-bromopyrazolo[1,5-a]pyridine-3-carboxylic acid from pyrazolo[1,5-a]pyridine was as follows: N-bromosuccinimide (3.06 g, 17.22 mmol) and sodium bicarbonate (4.34 g, 51.66 mmol) were sequentially added to a N,N-dimethylformamide (40 mL) solution of pyrazolo[1,5-a]pyridine-3-carboxylic acid (2.81 g, 17.22 mmol) in a solution of N,N-dimethylformamide (40 mL). The reaction mixture was stirred at room temperature for 4 h and then poured into water (100 mL). The resulting suspension was extracted twice with ethyl acetate and the organic layers were combined and dried over anhydrous magnesium sulfate. After filtration, the solvent was removed by concentration under reduced pressure. The crude product was purified by fast column chromatography (eluent: hexane/ethyl acetate = 8:2) to afford the target product 3-bromopyrazolo[1,5-a]pyridine (2.58 g, 76% yield). Mass spectrum (LRMS) showed m/z: 197 ([M+1]+). 1H-NMR (250 MHz, CDCl3) δ: 6.8 (t, 1H), 7.2 (t, 1H), 7.5 (d, 1H), 7.9 (s, 1H), 8.4 (d, 1H).
16205-46-2
174 suppliers
$68.00/100 mg
5910-12-3
130 suppliers
$49.00/100mg
Yield: 76%
Reaction Conditions:
with N-Bromosuccinimide;sodium hydrogencarbonate in N,N-dimethyl-formamide at 20; for 4 h;
Steps:
22.c
N-Bromosuccinimide (3.06 g, 17.22 mmol) and sodium hydrogen carbonate (4.34 g, 51.66 mmol) were added to a solution of pyrazolo[1 ,5-a]pyridine-3-carboxylic acid (Preparation 22b, 2.81 g, 17.22 mmol) in A/.A/'-dimethylformamide (40 mL) and the resulting mixture was stirred at room temperature for 4h before being poured over 100 mL of water. The resulting suspension was extracted twice with ethyl acetate and the combined organic layers were dried over magnesium sulphate, filtered and the solvent was evaporated. The crude product was purified by flash chromatography (8:2 hexane/ethyl acetate) to yield the title compound (2.58 g, 76%).LRMS (m/z): 197 (M+1)+.1H-NMR δ (250 MHz, CDCI3): 6.8 (t, 1 H), 7.2 (t, 1 H), 7.5 (d, 1 H), 7.9 (s, 1 H), 8.4 (d, 1 H).
References:
ALMIRALL, S.A.;BACH TA?A, Jordi;PAGES SANTACANA, Lluis, Miquel;TALTAVULL MOLL, Joan;EASTWOOD, Paul, Robert;GONZALEZ RODRIGUES, Jacob;GIULIO MATASSA, Victor WO2011/101161, 2011, A1 Location in patent:Page/Page column 99
![ETHYL PYRAZOLO[1,5-A]PYRIDINE-3-CARBOXYLATE](/CAS/GIF/16205-44-0.gif)
16205-44-0
145 suppliers
$11.00/250mg
5910-12-3
130 suppliers
$49.00/100mg