Preparation of THP‐Ester‐Derived Pyridinium‐Type Salts and their Reactions with Various Nucleophiles
作者:Hiromichi Fujioka、Yutaka Minamitsuji、Takahiro Moriya、Kazuhisa Okamoto、Ozora Kubo、Tomoyo Matsushita、Kenichi Murai
DOI:10.1002/asia.201200234
日期:2012.8
cis‐pyridinium‐type salts. These salts reacted with various nucleophiles, such as alcohols, azides, and organozinc reagents, to form nucleophilic‐substitution products. A characteristic feature of these processes was that they took place under mild conditions, which did not affect acid‐labile protecting groups. Furthermore, the reactions that employed azides and C‐nucleophiles generated 2,6‐trans products with high
已经开发了通过吡啶鎓型盐中间体进行的四氢吡喃基(THP)和相关的碳水化合物衍生的酯的异头位置的亲核取代。用TMSOTf(TMS =三甲基甲硅烷基)和2-取代的吡啶(例如2-对-甲苯基吡啶和2-甲氧基吡啶)处理6-取代的α-乙酰氧基-四氢吡喃可有效产生顺式py型盐。这些盐与各种亲核试剂(例如醇,叠氮化物和有机锌试剂)反应,形成亲核取代产物。这些过程的一个特征是它们发生在温和的条件下,并不影响对酸不稳定的保护基团。此外,使用叠氮化物和C-亲核试剂的反应生成具有高立体选择性的2,6-反式产物。