Syntheses of cis- and trans-4-benzyl- and 4-(3-methoxybenzyl)-2-methoxycarbonyl-1-methylpiperidines are described; amino-acids and amino-alcohols obtained from these compounds failed to cyclise. cis-2-Benzyl-4-ethoxycarbonyl-1-methylpiperidine has been made and its amino-acid hydrochloride cyclised in polyphosphoric acid at 160 °C to give 2,4,5,6,7-hexahydro-3-methyl-2,6-methano-1H-3-benzazonin-7-one
描述了顺式和反式-4-苄基和4-(3-甲氧基苄基)-2-甲氧基羰基-
1-甲基哌啶的合成;参见下文。从这些化合物获得的
氨基酸和
氨基醇无法环化。已制备出顺式-2-苄基-4-乙氧基羰基-
1-甲基哌啶,其
氨基酸盐酸盐在160°C的多
磷酸中环化,得到2,4,5,6,7-六氢-3-甲基-2, 6-methano-1 H -3-benzazonin-7-将其转化为几种衍
生物。
水解并环化通过两种途径获得的4-苄基-4-乙氧基羰基-
1-甲基哌啶,得到N-甲基螺并[
茚满-2,4'-
哌啶] -1-酮,其也被转化为几种衍
生物。