Described is a concise total synthesis of (-)-ambiguine P, a cycloheptane-containing member of the hapalindole alkaloids. The challenging pentacyclic framework of the natural product was assembled rapidly via a [4 + 3] cycloaddition reaction-inspired strategy, and the tertiary hydroxy group was introduced by an NBS-mediated bromination-nucleophilic substitution sequence.
描述了 (-)-ambiguine P 的简明全合成,它是 hapalindole 生物碱的一种含环庚烷的成员。通过受[4 + 3]环加成反应启发的策略快速组装天然产物的具有挑战性的五环骨架,并通过NBS介导的溴化-亲核取代序列引入叔羟基。
Enantioselective Synthesis of Functionalised Decalones by Robinson Annulation of Substituted Cyclohexanones, Derived from R-(−)-Carvone
作者:Ben J.M Jansen、Cindy C.J Hendrikx、Nikolai Masalov、Gerrit A Stork、Tommi M Meulemans、Fliur Z Macaev、Aede de Groot
DOI:10.1016/s0040-4020(00)00110-1
日期:2000.3
catalysed conjugate addition of methyl magnesium iodide to cyclohexenones and trapping of the enolate as its trimethylsilyl enol ether, followed by a trityl hexachloroantimonate (TrSbCl6) catalysed Mukaiyama-reaction, was applied to R-(−)-carvone. This proved to be an efficient method for the preparation of C-2, C-3 functionalised chiral cyclohexanones. These compounds were converted into their α-cyano ketones
Development of a novel synthetic method for medium‐sized trans‐cycloalkenes (TCAs) is described. Functionalized TCAs are readily prepared from simple cycloalkanones in a few steps, namely, enol silyl ether formation, [2+2] cycloaddition, and domino 4π electrocyclic ring opening/alkylation (conjugate addition). The first example of central‐to‐planar chirality transfer from enantiomerically enriched