反应详情

A solution of cis-2-(3,4-dimethoxyphenyl)-3-piperidinol (19.0 g, 80 mmoles, described in Example 4), ethanol (200 ml), 37% aqueous formaldehyde (7.4 g, 91 mmoles) and glacial acetic acid (8.0 g, 131 mmoles) is stirred at room temperature for 2 hours. The solution is diluted to 300 ml with ethanol and hydrogenated in the presence of Adams catalyst (400 mg). The residue is subjected to chromatography on silica gel using chloroform, 5% methanol-chloroform and finally 20% methanol-chloroform. The appropriate eluates are evaporated and the residue is dissolved in acetone. Maleic acid is added, followed by ether. The precipitate is collected and crystallized from acetonitrile-ether to give the title compound as the maleate salt, mp 132°-134° C.

1. customThe appropriate eluates are evaporated
2. dissolutionthe residue is dissolved in acetone
3. additionMaleic acid is added
4. customThe precipitate is collected
5. customcrystallized from acetonitrile-ether