Giofrè Sabrina, Keller Manfred, Lo Presti Leonardo, Beccalli Egle M, Molteni Letizia
DISFARM, Sezione di Chimica Generale e Organica "A. Marchesini", Università degli Studi di Milano, Via Venezian 21, 20133 Milano, Italy.
Institut für Organische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104 Freiburg im Breisgau, Germany.
Org Lett. 2021 Oct 15;23(20):7698-7702. doi: 10.1021/acs.orglett.1c02539. Epub 2021 Sep 27.
The Pd(II)-catalyzed reaction of -allyl-2-aminophenols in the presence of PhI(OCOR) as the oxidant resulted in an alkoxyacyloxylation process, with the formation of functionalized dihydro-1,4-benzoxazines. The reaction performed in the absence of palladium catalyst switched to an intramolecular Diels-Alder reaction (IMDA) pathway, which was the result of an oxidative dearomatization of the 2-aminophenol, nucleophilic addition, and Diels-Alder reaction cascade, highlighting the role of the oxidant as both a nucleophilic donor and an oxidizing agent.
在PhI(OCOR)作为氧化剂存在的情况下,钯(II)催化的-烯丙基-2-氨基苯酚反应导致了烷氧基酰氧基化过程,生成了官能化的二氢-1,4-苯并恶嗪。在没有钯催化剂的情况下进行的反应转变为分子内狄尔斯-阿尔德反应(IMDA)途径,这是2-氨基苯酚氧化脱芳构化、亲核加成和狄尔斯-阿尔德反应级联的结果,突出了氧化剂作为亲核供体和氧化剂的作用。