The nitrile ylide photochemically generated from 2,3-diphenyl-2H-azirine adds to both isomers of 3-(tosyloxymethylene)tetrahydrofuran-2-one with excellent regio- and stereoselectivity giving spiroheterocyclic products in moderate yields. X-Ray structure determination showed dibutolactone to have the E-configuration; the corresponding Z-isomer was prepared photochemically.
从2,3-二苯基-2H-氮杂环烷光化学生成的腈亚胺与3-(对甲苯磺酰氧甲基)四氢呋喃-2-酮的两种异构体都具有优异的区域和立体选择性加成,以适度的产率给出spiro杂环产物。X-射线结构测定显示二丁酸内酯具有E构型;相应的Z异构体是通过光化学方法制备的。