反应详情

A mixture of 4-(2-fluorophenyl)-4-hydroxy-1-methylpiperidine of Example 1a (15.8 g), 12 ml of 2-fluorobenzyl mercaptan and 20 ml of boron trifluoride etherate in 15 ml of glacial acetic acid is stirred at 65°-70° C. for 16 hours. The excess reagents are removed under reduced pressure, the residue is triturated with 300 ml of 0.5 N HCl and 100 ml of ether. After standing at 5°-10° C. for 30 minutes, a crystalline precipitate is filtered, air dried and made basic with 10% aqueous NH4OH. The liberated amine is taken up in either, dried and concentrated to a yellowish oil which is then converted to its maleate in ether, recrystallization of the crude salt from methanol-ether gives colorless prisms, m.p. 153°-154° C. of 4-(2-fluorobenzylthio)-4-(2-fluorophenyl)-1-methylpiperidine maleate.

1. customThe excess reagents are removed under reduced pressure
2. customthe residue is triturated with 300 ml of 0.5 N HCl and 100 ml of ether
3. waitAfter standing at 5°-10° C. for 30 minutes
4. filtrationa crystalline precipitate is filtered
5. customair dried
6. customdried
7. concentrationconcentrated to a yellowish oil which
8. customis then converted to its maleate in ether, recrystallization of the crude salt from methanol-ether