Lactones are known to react with the reagent generated in situ from CCl₄ and PPh₃ in a Wittig‐type fashion to give gem‐dichloro‐olefin derivatives. Such compounds are now shown to undergo reductive alkylation on treatment with organolithium reagents RLi to furnish acetylene derivatives bearing the substituent R at their termini (R=Me, n‐, sec‐, tert‐alkyl, silyl); the reaction can be catalyzed with either Cu(acac)₂ or Fe(acac)₃/1,2‐diaminobenzene. Two alkynol derivatives prepared in this way from readily accessible lactone precursors served as the key building blocks for the total syntheses of the cytotoxic marine macrolides tulearin A (1) and C (2). The assembly of these fragile targets hinged upon ring closing alkyne metathesis (RCAM) followed by a formal trans‐reduction of the resulting cycloalkynes via trans‐hydrosilylation/protodesilylation.

中文翻译：

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一种制备非末端炔烃的新方法：在Tulearin A和C的总合成中的应用

已知内酯会以Wittig型方式与CCl ₄和PPh ₃原位生成的试剂反应，生成宝石二氯烯烃衍生物。现已证明此类化合物在用有机锂试剂RLi处理后会发生还原烷基化反应，从而提供在其末端带有R取代基的乙炔衍生物（R = Me，n-，仲-，叔烷基，甲硅烷基）；该反应可以用Cu（acac）₂或Fe（acac）₃催化/ 1,2-二氨基苯 从容易获得的内酯前体以这种方式制备的两种炔醇衍生物，是细胞毒性海洋大环内酯类鹅膏蛋白A（1）和C（2）的总合成的关键组成部分。这些易碎目标的组装取决于闭环炔烃复分解（RCAM），然后通过反式氢化硅烷化/原去甲硅烷基化对所得的环炔烃进行正式的反式还原。