Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstraße 40, 48419, Münster, Germany.
Chemistry. 2018 Oct 17;24(58):15529-15532. doi: 10.1002/chem.201804308. Epub 2018 Oct 1.
Borrowing hydrogen is a powerful and green technique that allows readily available alcohols to be used as alkylating agents and produces water as the only by-product. Nevertheless, harsh conditions such as high temperatures and organic solvents are usually required. Herein, we present a strategy to perform the α-alkylation of ketones in aqueous media at mild temperatures by combining borrowing hydrogen with phase-transfer catalysis. A broad scope of methyl ketones was functionalized with alkyl and benzyl alcohols in moderate to good yields at 40 °C. The protocol was also highly effective at large scale and room temperature.
borrowing hydrogen 是一种强大且绿色的技术，可使易得的醇类化合物作为烷基化试剂，并仅生成水作为唯一的副产品。然而，通常需要苛刻的条件，如高温和有机溶剂。在此，我们提出了一种在温和条件下在水相介质中通过结合 borrowing hydrogen 和相转移催化来实现酮的 α-烷基化的策略。在 40°C 下，多种甲基酮与烷基和苄醇以中等至良好的收率实现了功能化。该方案在大规模和室温下也具有很高的效率。
