Asenapine → Asenapine Maleate

Participants

Reaction Conditions

Reaction Steps

A mixture of 9.52 g of the solid containing trans-5-chloro-2,3,3a,12b-tetrahydro-2-methyl-1H-dibenzo[2,3;6,7]-oxepino[4,5-c]pyrrole obtained in Example 4 and 25 mL of ethanol was heated to 60° C., and then 4.25 g (36.6 mmol) of maleic acid was added to obtain a homogeneous solution. Approximately 0.2 g of active carbon (SEISEI SHIRASAGI, product of Takeda Pharmaceutical Co., Ltd.) was added to the solution and the mixture was stirred at the same temperature for 25 minutes. The mixture was filtered at the same temperature to obtain a filtrate. The filtered active carbon was washed with 10 mL of ethanol and the obtained wash solution was combined with the previously obtained filtrate. The obtained solution was cooled to 40° C., and trans-5-chloro-2,3,3a,12b-tetrahydro-2-methyl-1H-dibenzo[2,3;6,7]-oxepino[4,5-c]pyrrole maleate seed crystals were added. The obtained mixture was cooled to 0-5° C. and then stirred for 2 hours. The precipitated crystals were separated off by filtration, and the crystals were washed with approximately 10 mL of cold ethanol and dried to obtain 7.87 g of trans-5-chloro-2,3,3a,12b-tetrahydro-2-methyl-1H-dibenzo[2,3;6,7]-oxepino[4,5-c]pyrrole maleate as a white solid. The yield was 63% (based on trans-form).

Provenance & Evidence