Department of Chemistry, Clemson University, Clemson, South Carolina 29631, United States.
Department of Chemistry, Faculty of Applied Sciences, University of Sri Jayewardenepura, Gangodawila, Nugegoda-10250, Sri Lanka.
J Org Chem. 2022 Jun 3;87(11):7494-7500. doi: 10.1021/acs.joc.2c00280. Epub 2022 May 12.
Our previous method to access the diazacyclobutene scaffold did not allow for modification of the substituent originating from the 1,2,4-triazoline-3,5-dione component. We have circumvented this challenge and expanded access to additional structural diversity of the scaffold. A telescoped urazole oxidation and Lewis acid-catalyzed cyclization provided R-substituted diazacyclobutenes. Calcium hypochlorite-mediated oxidation of urazoles followed by MgCl-catalyzed cyclization of the resulting triazolinediones with thioalkynes promoted the formation of diazacyclobutenes bearing substitution at the R position originating from the triazolinedione component.
我们之前获取二氮杂环丁烯支架的方法无法修饰源自 1,2,4-三唑-3,5-二酮部分的取代基。我们已经规避了这一挑战，并扩展了支架的更多结构多样性。缩合的尿嘧啶氧化和路易斯酸催化的环化提供了 R 取代的二氮杂环丁烯。次氯酸钠介导的尿嘧啶氧化，随后 MgCl 催化的三唑啉二酮与硫代炔烃的环化，促进了 R 位置取代的二氮杂环丁烯的形成，其取代基源自三唑啉二酮部分。
