Piperazine → HCID 47002240, compound

Participants

Reaction Conditions

Reaction Steps

A nitrogen-flushed, suitably equipped 22 L 4-neck round bottom flask is charged with 1392 g (8.78 mol, 1.0 eq.) of 5-chloro-2-nitropyridine (A2d), 1512 g (17.56 mol, 2.0 eq.) of piperazine (A2c) and 11,340 g (14,000 mL) of n-butanol. The resulting suspension is stirred and heated to 95° C. This temperature is maintained for at least 24 h or until the remaining starting material, A2d, is ≧2% (area normalization) as determined by HPLC analysis. The resulting slurry is cooled to 25° C. over 1 h. The solids are filtered through a polypropylene filter pad. The filter cake is washed twice with a total of 2267 g (2×1300 mL) of isopropyl acetate. The solids are dried at 60° C. for 16 h, to afford 1769 g (82.3%, uncorrected) of A2b as a yellow, crystalline solid, mp>230° C. (dec.).

Provenance & Evidence