Jeffrey Jenna L, Terrett Jack A, MacMillan David W C
Merck Center for Catalysis, Princeton University, Princeton, NJ 08544, USA.
Science. 2015 Sep 25;349(6255):1532-6. doi: 10.1126/science.aac8555. Epub 2015 Aug 27.
The efficiency and selectivity of hydrogen atom transfer from organic molecules are often difficult to control in the presence of multiple potential hydrogen atom donors and acceptors. Here, we describe the mechanistic evaluation of a mode of catalytic activation that accomplishes the highly selective photoredox α-alkylation/lactonization of alcohols with methyl acrylate via a hydrogen atom transfer mechanism. Our studies indicate a particular role of tetra-n-butylammonium phosphate in enhancing the selectivity for α C-H bonds in alcohols in the presence of allylic, benzylic, α-C=O, and α-ether C-H bonds.
在存在多个潜在氢原子供体和受体的情况下，有机分子中氢原子转移的效率和选择性往往难以控制。在此，我们描述了一种催化活化模式的机理评估，该模式通过氢原子转移机制实现了醇与丙烯酸甲酯的高度选择性光氧化还原α-烷基化/内酯化反应。我们的研究表明，在存在烯丙基、苄基、α-C=O和α-醚C-H键的情况下，磷酸四丁铵在提高醇中α C-H键的选择性方面具有特殊作用。
