ChemicalBook CAS DataBase List 5-BROMO-1H-PYRAZO[3,4-B]PYRIDINE

5-BROMO-1H-PYRAZO[3,4-B]PYRIDINE synthesis

5synthesis methods

Product Name:5-BROMO-1H-PYRAZO[3,4-B]PYRIDINE
CAS Number:875781-17-2
Molecular formula:C6H4BrN3
Molecular Weight:198.02

875781-15-0 Synthesis

5-Bromo-2-fluoropyridine-3-carboxaldehyde

875781-15-0
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$6.00/1g

875781-17-2
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$7.00/250mg

Yield:875781-17-2 46%

Reaction Conditions:

with hydrazine in ethanolHeating / reflux;

Steps:

D-1
Preparation of 5-bromo-1H-pyrazolo[3,4-b]pyridine (D-1-3). D-1-2 ^D"1-³A solution of compound D-1-2 (20 g, 0.1 mol) and anhydrous hydrazine (18 g, 0.56 mol) in ethanol was heated to reflux overnight. TLC (petroleum ether/EtOAc 2:1 ) indicated complete consumption of starting material. The reaction mixture was concentrated in vacuo to a volume of about 50 ml_ and poured into water (500 ml_), the resulting mixture was filtered. The cake was washed with water (50 ml_^χ3) and ether (20 ml_^χ3), then dried in vacuo to yield compound D-1-3 (9.0 g, 46%) as a yellow solid.

References:

PFIZER INC. WO2009/16460, 2009, A2 Location in patent:Page/Page column 99-100

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2065-75-0 Synthesis