Synthesis of Azetidine Nitrones and Exomethylene Oxazolines through a Copper(I)-Catalyzed 2,3-Rearrangement and 4π-Electrocyclization Cascade Strategy
作者:Jin-Qi Zhang、Pei-Wen Qiu、Cui Liang、Dong-Liang Mo
DOI:10.1021/acs.orglett.2c03156
日期:2022.10.28
A variety of azetidine nitrones are prepared in moderate to good yields through copper(I) combined with 2-aminopyridine to catalyze skeletal rearrangement of O-propargylic oximes. Mechanistic studies reveal that the reaction undergoes a copper(I)-catalyzed tandem [2,3]-rearrangement, 4π-electrocyclization, ring opening, and recyclization over four steps in one pot. Substituents at the terminus of alkyne
通过铜 (I) 与 2-氨基吡啶结合催化O-炔丙基肟的骨架重排,以中等到良好的产率制备了多种氮杂环丁烷硝酮。机理研究表明,该反应在一锅中经历了铜 (I) 催化的串联 [2,3]-重排、4π-电环化、开环和再循环四个步骤。炔烃和肟部分末端的取代基分别对氮杂环丁烷硝酮和外亚甲基恶唑啉的形成有显着影响。此外,所获得的氮杂环丁烷硝酮可以很容易地参与与炔酸酯的[3 + 2]环加成反应,并以溴[2.2]-对环芳烷为原料,通过五步合成了[2.2]-对环芳烷衍生的氮杂环丁烷硝酮,产率为45%。