2-丁基-6-硝基吲哚的合成

Synthesis of 2-butyl-6-nitroindole

介绍了一步关环合成2-丁基-6-硝基吲哚的新方法。室温氮气保护下,2-氨基-4硝基苯酚与三氟乙酰酐反应进行氨基保护,得到的2-(N-三氟甲基乙酰基)氨基-4-硝基苯酚与N-苯基双(三氟甲烷磺酰)亚胺(PhNTf2)在强碱NaH作用下,生成三氟甲基磺酸酯,收率82.6%。之后,70～80℃氮气保护下,Pd(PPh3)4催化剂作用,与正己炔一步关环合成2-丁基-6-硝基吲哚,收率33.3%。产物结构经红外光谱、核磁共振和质谱检测并证实。将目标产物进行单晶培养,经单晶X衍射检测表征,阐明了结构。

2-Butyl-6-nitroindole was synthesized via the stepwise Pd-catalyzed cross-coupling of a triflate with hexyne starting from 2-amino-4-nitrophenol, where the amino group was protected by trifluoroacetic group. The triflate was obtained from the reaction of N-（2-hydroxy-4-nitrophenyl） trifluoroacetamide with PhNTf2 catalyzed by Nail. Structure of the product in each steps was checked and determined by IR, ^1H NRM, ^13C NMR and MS.