NHPI- and TBAI-Co-Catalyzed Synthesis of Allylic Esters from Toluene Derivatives and Alkenes
作者:Hongmei Deng、Xueshun Jia、Jian Li、Chengliang Li、Tao Jin、Chunju Li
DOI:10.1055/s-0036-1591748
日期:2018.4
An N-hydroxyphthalimide (NHPI) and tetrabutylammonium iodide (TBAI) co-catalyzed oxidative coupling reaction of toluene derivatives and alkenes has been disclosed. This method can serve as a new strategy to access allylic ester using toluene derivatives as oxyacylating reagent. This metal-free protocol also features the readily available starting materials, broad substrate scope, and mild reaction
Benzylic C–H Esterification with Limiting C–H Substrate Enabled by Photochemical Redox Buffering of the Cu Catalyst
作者:Dung L. Golden、Chaofeng Zhang、Si-Jie Chen、Aristidis Vasilopoulos、Ilia A. Guzei、Shannon S. Stahl
DOI:10.1021/jacs.3c01662
日期:2023.5.3
Copper-catalyzed radical-relay reactions provide a versatile strategy for selective C–H functionalization; however, reactions with peroxide-based oxidants often require excess C–H substrate. Here, we report a photochemical strategy to overcome this limitation by using a Cu/2,2′-biquinoline catalyst that supports benzylic C–H esterification with limiting C–H substrate. Mechanistic studies indicate that
铜催化的自由基中继反应为选择性 C-H 官能化提供了一种通用策略;然而,与过氧化物基氧化剂的反应通常需要过量的 C-H 底物。在这里,我们报告了一种光化学策略,通过使用 Cu/2,2'-联喹啉催化剂来克服这一限制,该催化剂支持限制 C-H 底物的苄基 C-H 酯化反应。机理研究表明,蓝光照射促进羧酸盐到铜的电荷转移,将静止态 Cu II还原为 Cu I,从而激活过氧化物以生成烷氧基自由基氢原子转移物质。这种“光化学氧化还原缓冲”引入了一种独特的策略来维持自由基接力反应中铜催化剂的活性。
Mechanochemical Mitsunobu Reactions
作者:Matthew T. J. Williams、Laura Adarve Cardona、Carsten Bolm
DOI:10.1002/adsc.202400296
日期:2024.5.21
using stainless steel milling media, the product 3 a was obtained in 80% yield (entry 1). Deviating from these conditions, such as by using DIAD in place of DBAD, led to a lower yield of 3 a (entry2). Decreasing the milling time to 5 min or 1 min, or the milling frequency to 25 Hz led to lower yields of 3 a, also (entries 3–5). Additionally, carrying out the reaction in a jar fabricated from poly