Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, NH, 03755, USA.
Angew Chem Int Ed Engl. 2016 Oct 10;55(42):13099-13103. doi: 10.1002/anie.201606962.
A convergent coupling reaction is described that enables the stereoselective construction of angularly substituted trans-fused decalins from acyclic precursors. The process builds on our alkoxide-directed titanium-mediated alkyne-alkyne coupling and employs a 1,7-enyne coupling partner. Overall, the reaction is thought to proceed through initial formation of a tetrasusbstituted metallacyclopentadiene, stereoselective intramolecular [4+2] cycloaddition, elimination, isomerization, and regio- and stereoselective protonation. Distinct from our early studies directed at the synthesis of trans-fused hydrindanes, the current annulative coupling reveals an important effect of TMSCl in controlling the final protonation-the event that establishes the stereochemistry of the ring fusion.
描述了一种收敛偶联反应，可从非环前体立体选择性构建角取代的反式稠合十氢化萘。该过程建立在我们的醇盐定向钛介导的炔烃-炔烃偶联和使用 1,7-烯炔偶联伙伴的基础上。总体而言，反应被认为通过四取代金属环戊二烯的初始形成、立体选择性的分子内[4+2]环加成、消除、异构化以及区域和立体选择性的质子化来进行。与我们早期针对反式稠合茚满合成的研究不同，当前的环合偶联反应揭示了 TMSCl 在控制最终质子化中的重要作用-该事件确定了环融合的立体化学。
