申请人:Meunier Jean-Francois
公开号:US20050176752A1
公开(公告)日:2005-08-11
A process is disclosed for preparation of piperidine derivatives, preferably 1,3-dioxolo [4,5-c] piperidin-7-ols such as (3aS, 4R, 7S, 7aR)-2,2,4-trimethyl-1,3-dioxolo [4,5-c] piperidin-7-ol and its polyhydroxylated derivatives. In a preferred process, 2,3-O-isopropylidene-1,4-lactone (A) is reacted with methanesulfonyl chloride to form (3aR, 4S, 6aR) methanesulfonic acid 2,2-dimethyl-6-oxo-tetrahydro-furo[3,4-d][1,3]dioxol-4-ylmethyl (B). Compound (B) is then reacted with methylmagnesium halide to form (3aR, 4S, 6aR)-methanesulfonic acid 6-hydroxy-2,2,6-trimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-ylmethyl ester (C), which is reacted with phthalimide to form (3aR, 4S, 6aR)-2-(6-hydroxy-2,2,6-trimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-ylmethyl)-isoindole-1,3-dione (D). Compound (D) is reacted with hydrazine to form (3S, 7S, 7aR)-2,2,4-trimethyl-3a,6,7,7a-tetrahydro-[1,3]dioxolo[4,5-c]pyridin-7-ol (E), which is hydrogenated to give the corresponding 1,3-dioxolo [4,5-c] piperidin-7-ol (F). The synthesis has an overall yield which is typically greater than 50% and avoids the use of reagents such as triflic anhydride and sodium azide.
本发明揭示了一种制备吡啶衍生物的方法,优选为制备1,3-二氧杂环[4,5-c]吡啶-7-醇,例如(3aS,4R,7S,7aR)-2,2,4-三甲基-1,3-二氧杂环[4,5-c]吡啶-7-醇及其多羟基衍生物。在优选的方法中,2,3-O-异丙基-1,4-内酯(A)与甲磺酰氯反应,形成(3aR,4S,6aR)-甲磺酸2,2-二甲基-6-氧代四氢呋[3,4-d][1,3]二噁烷-4-基甲酯(B)。化合物(B)然后与甲基镁卤反应,形成(3aR,4S,6aR)-甲磺酸6-羟基-2,2,6-三甲基-四氢呋[3,4-d][1,3]二噁烷-4-基甲酯(C),它与邻苯二甲酰亚胺反应形成(3aR,4S,6aR)-2-(6-羟基-2,2,6-三甲基-四氢呋[3,4-d][1,3]二噁烷-4-基甲基)-异吲哚-1,3-二酮(D)。化合物(D)与肼反应形成(3S,7S,7aR)-2,2,4-三甲基-3a,6,7,7a-四氢-[1,3]二氧杂环[4,5-c]吡啶-7-醇(E),它经氢化反应得到相应的1,3-二氧杂环[4,5-c]吡啶-7-醇(F)。该合成方法的总收率通常大于50%,避免使用三氟乙酰酐和偏氮化钠等试剂。