Synthesis and 1-oxide/3-oxide interconversion of 4-substituted benzodifuroxans: a thorough NMR and theoretical study of the structure of 4-fluoro- and 4-chloro-benzodifuroxan
作者:Cyril Jovené、Morgane Jacquet、Elena A. Chugunova、Sergey V. Kharlamov、Régis Goumont
DOI:10.1016/j.tet.2016.03.021
日期:2016.4
2,4,6-trifluoro-1,3-dinitrobenzene implying a safe synthesis. Importantly, due to the 1-oxide/3-oxide interconversion, NMR spectra have shown that this compound exists as a mixture of four tautomers. The presence of the fluorine atom allows the determination of the 1H and 13C NMR parameters of the two main isomers. Interestingly, 4-fluorobenzodifuroxan has been partially and totally deoxygenated upon
从2,4,6-三氟-1,3-二硝基苯一步合成完成了新的4-氟苯并二呋喃,这意味着安全的合成。重要的是,由于1氧化物/ 3氧化物的相互转化,NMR光谱表明该化合物以四种互变异构体的混合物形式存在。氟原子的存在可以确定两种主要异构体的1 H和13 C NMR参数。有趣的是,在分别与一当量和两当量的亚磷酸三乙酯加热时,4-氟苯并二呋喃已被部分和完全脱氧。苯并呋喃山类似物以中等收率获得,并易于与氨反应,首次导致生成4-氨基苯并二呋喃。