Sorbonne Université, Faculté des Sciences et Ingénierie, CNRS , Institut Parisien de Chimie Moléculaire, IPCM , 4 place Jussieu , 75005 Paris , France.
Centro de Química Estrutural, Instituto Superior Técnico , Universidade de Lisboa , Av Rovisco Pais 1 , 1049-001 Lisbon , Portugal.
Org Lett. 2018 Apr 20;20(8):2346-2350. doi: 10.1021/acs.orglett.8b00689. Epub 2018 Apr 9.
A Pd-catalyzed direct C-alkenylation of azine N-oxides with allyl acetate is disclosed. The products are formed through an allylation/isomerization cascade process. The use of a tri- tert-butylphosphonium salt as the ligand precursor and KF is mandatory for optimal yields. When cinnamyl acetate is used, the same catalytic system promotes C-cinnamylation of the azine N-oxide without subsequent isomerization. A mechanism is proposed on the basis of experimental studies and DFT calculations.
本文报道了钯催化的嗪 N-氧化物与醋酸烯丙酯的直接 C-烯丙基化反应。产物通过烯丙基化/异构化级联过程形成。使用三-叔丁基膦盐作为配体前体和 KF 是获得最佳产率的必要条件。当使用肉桂基醋酸酯时，相同的催化体系促进嗪 N-氧化物的 C-肉桂基化，而无需随后的异构化。基于实验研究和 DFT 计算提出了一种反应机理。
