1-hydroxy-4,4,5,5-tetramethyl-2-(2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-3-yl)-4,5-dihydroimidazole                                                                                                                                                              在
                                                                                                                                                                                 
lead dioxide                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
氯仿                                                                                  为溶剂,
                                                                                                                                                    反应 0.17h,
                                                                                                                以91%的产率得到2-(2,5-dihydro-2,2,5,5-tetramethyl-1H-pyrrol-3-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-yloxyl radical