Silver-Catalyzed Enantioselective Propargylation Reactions of <i>N</i>‑Sulfonylketimines

The enantioselective silver-catalyzed propargylation of N-sulfonylketimines is described. This reaction proceeds in high yield and excellent enantiomeric ratio and is compatible with a wide variety of diaryl- and alkylketimines. Synthetic transformations of homopropargylic products via enyne ring-closing metathesis, Sonogashira cross-coupling, and reduction reactions proceed with high stereochemical fidelity. Both allenyl and propargyl borolane reagents can be used to obtain homopropargylic products, a distribution most consistent with a mechanism involving transmetalation of the silver catalyst with the borolane reagent.本文报道了N-磺酰基酮亚胺（N-sulfonylketimines）的对映选择性银催化炔丙基化反应。该反应兼具优异的反应收率与极高的对映体比例，可兼容多种二芳基酮亚胺与烷基酮亚胺底物。所得高炔丙基产物（homopropargylic products）可通过炔烃闭环复分解（enyne ring-closing metathesis）、Sonogashira交叉偶联（Sonogashira cross-coupling）及还原反应进行合成转化，且转化过程中立体化学保真度优异。联烯基（allenyl）与炔丙基硼环戊烷（borolane）试剂均可用于制备该类高炔丙基产物，这一试剂适用性特征与银催化剂与硼环戊烷试剂发生转金属化的反应机理高度吻合。