| 摘要 |
<p>Prepn. of piperdine derivs. of formula (I, R4isH) comprises firstly reacting a thiobenzoic acid deriv. of formula (II, Y is H) with ClCO2R5. Reactor is at -15 to 0 degrees C in an organic solvent in presence of NET3. The prod. of formula (I, Y is CO2R5) is reacted in situ a 0-20 degrees C with an amine of formula (III). The prod. of formula (I) is hydrolysed if R4 is other than H. In the formulae, X is Cl or Br.R1 is 1-6C alkyl. R2 and R3 are both H, or one is Cl in the 3- or 4- position or Me or OMe in the 4- position and the other is H, or R2 and R3 together form 3,4-OCH2O. R4 is H, CHO or 2-5C alkanoyl opt. substd. by 1-3 halo. R5 is 1-6C alkyl. (I, R4 is H) are antagonists of dopamine or depaminergic agents. The process gives ca. 95% yield. Inexpensive solvents can be used.</p> |
