Oxalic Acid → HCID 20065656, compound

Participants

Reaction Steps

A solution of 3-(N-methyl-N-phenylamino)-1-isoindolinone (10 g) in anhydrous dimethylformamide (200 cc) is added to a suspension of sodium hydride (as a 50% suspension in oil) (2.2 g) in anhydrous dimethylformamide (200 cc) at a temperature close to 20° C. in the course of 30 minutes and agitation is continued for 1 hour. Then, a solution of 3-(4-phenyl-1,2,3,6-tetrahydro-1-pyridyl)-1-bromopropane (13 g) in dimethylformamide (100 cc) is added in the course of 15 minutes, and agitation is continued for a further 20 hours. The solution obtained is evaporated to dryness under reduced pressure (1 mm Hg; 0.1 kPa). The residue obtained is dissolved in methylene chloride (200 cc) and washed with distilled water (3×50 cc). The organic extracts are dried over anhydrous magnesium sulphate, filtered and concentrated to dryness under reduced pressure (20 mm Hg; 2.7.kPa) at 40° C. The residue obtained is dissolved in methylene chloride (40 cc) then poured onto silica (800 g) contained in a column of 8 cm diameter. Elution is carried out with a mixture of methylene chloride and methanol (95-5 by volume). The first 2300 cc are eliminated and the next 1100 cc are concentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa). The residue obtained is dissolved in methyl ethyl ketone (50 cc). A solution of oxalic acid (1.1 g) in methyl ethyl ketone (15 cc) is added, and agitation continued for 1 hour at a temperature close to 20° C. The precipitate formed is separated by filtration. 5.4 g of 3-(N-methyl-N-phenylamino)-2-[3-(4-phenyl-1,2,3,6-tetrahydro-1-pyridyl)propyl]-1-isoindolinone oxalate are obtained, melting at 159° C.

Provenance & Evidence