Process for preparing trimeric .DELTA..sup.1 -piperideins and trimeric
申请人:Hoechst Aktiengesellschaft
公开号:US04123434A1
公开(公告)日:1978-10-31
Trimeric piperideins and trimeric pyrrolidine are prepared by saponification of 1-acyl-2-alkoxypiperidines or pyrrolidines of the general formula ##STR1## in which n means 2 or 3 R.sub.1 represents hydrogen or a linear or branched C.sub.1 -C.sub.4 alkyl radical and R.sub.2 represents a linear or branched C.sub.1 -C.sub.4 alkyl radical In aqueous and/or alcoholic solution in known manner in the presence of a strong acid or base and trimerizing the reaction product at a pH equal to or greater than 8. The compounds are valuable intermediates for the manufacture of alkaloids and other pharmaceutically effective substances and N-heterocycles.
Substitution reactions of 2-phenylsulphonyl-piperidines and -pyrrolidines with carbon nucleophiles: Synthesis of the pyrrolidine alkaloids norruspoline and ruspolinone
作者:Dearg S. Brown、Philippe Charreau、Thomas Hansson、Steven V. Ley
DOI:10.1016/s0040-4020(01)86388-2
日期:1991.1
treatment with benzenesulphinic acid. On reaction with various carbon nucleophiles these sulphones gave good yields of substitution products. Typical nucleophiles used in these studies were organometallic reagents derived from Grignard reagents and zinc halide together with silyl enol ethers, silyl ketene acetals, allylsilanes and trimethylsilyl cyanide in the presence of a Lewis acid. These methods