Novel Five- and Six-Membered Rings of Phosphorus–Selenium Heterocycles from Selenation of Amido-Schiff Bases

作者：Guoxiong Hua, David B. Cordes, Alexandra M. Z. Slawin, J. Derek Woollins · 发表于：ACS Omega · 年份：2020 · DOI：10.1021/acsomega.0c01064 · 被引用次数：10 · 研究领域：Organoselenium and organotellurium chemistry、Synthesis and Reactivity of Sulfur-Containing Compounds、Organophosphorus compounds synthesis

Woollins' reagent, [2,4-bis(phenyl)-1,3-diselenadiphosphetane-2,4-diselenide], serving as a selenating-reductive cycloaddition reagent, reacts with nonconjugated amido-Schiff bases to give the corresponding six-membered 1,3,4-selenadiazoles via a ring-expansion accompanied by an additional selenation/cyclization to the imine bond and C=O group; meanwhile, under the same reaction conditions, the selenation of conjugated amido-Schiff bases leads to a series of fused heterocycles with two five-membered rings. Eight single-crystal X-ray structures confirming the formation of these five- and six-membered heterocycles are discussed.