L-Tartaric acid → 1-Methyl-1H-pyrazole-4-sulfonic acid {2-[3'-(4-methoxymethyl-phenyl)-2,3,5,6-tetrahydro-[1,2']bipyrazinyl-4-yl]-ethyl}-methyl-amide L-tartrate

Participants

Reaction Conditions

Reaction Steps

1-Methyl-1H-pyrazole-4-sulfonic acid {2-[3′-(4-methoxymethyl-phenyl)-2,3,5,6-tetrahydro-[1,2′]bipyrazinyl-4-yl]-ethyl}-methyl-amide (1.0 equivalents) and L-tartaric acid (0.95 equivalents) is suspended in 2B3 EtOH (10 volumes) and heated to at least 75° C. for at least 60 min. The resulting slurry is then cooled to 20° C. over at least 90 min. After granulating at 20° C. for at least 60 min., the resulting solids are filtered and washed with 2B3 EtOH (2×3 volumes). The cake is then dried at 50° C. under vacuum with nitrogen bleed for at least 12 hr. 1-Methyl-1H-pyrazole-4-sulfonic acid {2-[3′-(4-methoxymethyl-phenyl)-2,3,5,6-tetrahydro-[1,2′]bipyrazinyl-4-yl]-ethyl}-methyl-amide L-tartrate is isolated as an off-white solid (92% yield). m.p. 161° C.

Provenance & Evidence