2-Hydroxy-1,2,3-propanetricarboxylic acid hydrate (1:1) → Ethyl 2-[6-[3-[4-(Diphenylmethoxy)piperidino]propylamino]imidazo[1,2-b]pyridazin-2-yl)-2-methylpropionate Citrate

Participants

Reaction Steps

In 8 mL of ethanol, 1.667 g of the ethyl 2-[6-[3-[4-(diphenylmethoxy)piperidino]propylamino]imidazo[1,2-b]pyridazin-2-yl]-2-methylpropionate synthesized in Reference Example 2C was dissolved, and 0.631 g of citric acid monohydrate was added thereto and dissolved under heating, followed by concentration under reduced pressure. To the residue was added 23 mL of ethyl acetate, and the crystals formed were collected by filtration and washed with 12 mL of ethyl acetate. To the crystals was added 30 mL of methanol and the crystals were dissolved under heating, followed by concentration under reduced pressure. To the residue was added 30 mL of ethanol and the residue was then dissolved. After still standing, the crystals formed were collected by filtration, washed with 10 mL of ethanol and dried to yield 2.007 g of the title compound.

Provenance & Evidence