Department of Chemistry, Zhejiang Normal University , 688 Yingbin Road, Jinhua 321004, People's Republic of China.
J Org Chem. 2013 Nov 1;78(21):10894-901. doi: 10.1021/jo4018793. Epub 2013 Oct 18.
Described herein is a novel method for the synthesis of 3,4,5-trisubstituted 2-oxazolones featuring the first Pd-catalyzed dehydrogenative alkenylation of 2-oxazolones, which is realized by employing 10 mol % of Pd(OAc)2 as the catalyst and the use of readily available Cu(OAc)2 as the oxidant. A wide range of functional groups, such as F, Cl, Br, OMe, ester, ketone, amide, alkyl, and aryl substituents, are found to be compatible under the reaction conditions. The utilization of the C-H functionalization strategy provides a straightforward, convenient, and highly atom-economical approach for the construction of 3,4,5-trisubstituted 2-oxazolones. It is worth noting that the 4-alkenyl 2-oxazolones can be smoothly converted into naphtho[1,2-d]oxazol-2-ones via a photochemical transformation.
本文描述了一种新颖的合成 3,4,5-三取代 2-噁唑酮的方法，该方法通过使用 10 mol%的 Pd(OAc)2 作为催化剂和易得的 Cu(OAc)2 作为氧化剂，实现了 2-噁唑酮的首例 Pd 催化脱氢烯基化反应。该反应条件下，具有各种官能团，如 F、Cl、Br、OMe、酯、酮、酰胺、烷基和芳基取代基的底物都具有兼容性。C-H 官能化策略的应用为构建 3,4,5-三取代 2-噁唑酮提供了一种直接、方便、高效原子经济性的方法。值得注意的是，4-烯基 2-噁唑酮可以通过光化学转化顺利转化为萘并[1,2-d]噁唑-2-酮。
