Zhang Jun, Wu Weijie, Zhang Xuejun, Zhang Gengtao, Xu Sheng, Shi Min
Key Laboratory for Advanced Materials; Institute of Fine Chemicals, School of Chemistry&Molecular Engineering, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237 (China).
Chem Asian J. 2015 Mar;10(3):544-7. doi: 10.1002/asia.201403281. Epub 2015 Feb 2.
Facile synthesis of bicyclic ureas by NIS/PhI(OAc)2-mediated diamination/oxidation of N-alkenyl formamidines is reported. Bulky aromatic groups such as 2,6-diisopropylphenyl and mesityl and alkyl groups were tolerated towards the process. Several control experiments have been performed, and the reaction outcomes indicate that the oxidation process is probably concerted with the diamination cyclization, and succinimide generated from NIS-mediated aminoamidiniumation step promoted the PhI(OAc)2-mediated oxidation step. The new methodology provides an efficient method for the synthesis of fused tricyclic ureas.
报道了通过NIS/PhI(OAc)₂介导的N-烯基甲脒的双胺化/氧化反应简便合成双环脲。该过程对诸如2,6-二异丙基苯基、均三甲苯基等庞大的芳基以及烷基具有耐受性。进行了多项对照实验，反应结果表明氧化过程可能与双胺化环化协同进行，并且由NIS介导的氨基脒化步骤生成的琥珀酰亚胺促进了PhI(OAc)₂介导的氧化步骤。该新方法为稠合三环脲的合成提供了一种有效方法。
