在碳酸钾作用下,1-硝基环己烯与异氰基乙酸乙酯在乙醇中发生Barton-Zard反应,得到2-乙氧羰基,4,5,6,7-四氢异吲哚。该方法使用碳酸钾代替有机碱DBU和易水解的叔丁醇钾,用乙醇代替四氢呋喃,溶剂毒性低,操作简便,产率更高。
2-Ethoxycarbonyl-4, 5, 6, 7-tetrahydroisoindole was synthesized via the Barton-Zard reaction in ethanol from 1-nitrocyclohexene and ethyl isocyanoacetate in the presence of potassium carbonate. The improved method, which employed potassium carbonate instead of the organic base, 1,8-diazabicyclo [ 5.4.0 ] undec-7-enc(DBU) and the easily hydrolyzed tert-butoxide, and ethanol instead of THF respectively, had higher yield, with avoidance of using toxic reagents, and was convenient in operation.