6-bromo-4-methoxypyrazolo[1,5-a]pyridine-3-carbonitrile

Description

6-bromo-4-methoxypyrazolo[1,5-a]pyridine-3-carbonitrile is a pharmaceutical intermediate ingredient for the preparation of Selpercatinib, indicated for the treatment of patients with advanced cancers who test positive for certain RETs.

Uses

6-bromo-4-methoxypyrazolo[1,5-a]pyridine-3-carbonitrile is an organic intermediate for laboratory R&D processes.

Synthesis

The DMF 10L solution of 2,4,6-trimethylbenzenesulfonic acid 3-bromo-5-methoxypyridinamine salt 2000g (4.96mol, 1.0eq), 2-chloropropene cyanide (7.44mol, 1.5eq) was added with potassium carbonate 684g (4.96mol, 1.0eq) and stirred at 20-30°C for 8h. Then the mixtrue was heated with dropwise 1132g (7.44mol, 1.5eq) of diazabicyclo at 50-60°C for 20h. After the reaction is finished and poured into water 30 L at RT. the solution was filtered, washed with water and recrystallized in ethanol to give a pale yellow solid, 6-bromo-4-methoxypyrazolo[1,5-a]pyridine-3-carbonitrile (702g 56%).