1: 63 percent / 1,8-diazabicyclo<5.4.0>undec-7-ene (DBU) / toluene / 1.5 h / 90 °C 2: (dimethylamino)pyridine / acetonitrile 3: 85 percent / tributyltin hydride, AIBN / toluene / 120 °C 4: 1.) LiN3, benzoic acid, 2.) 0.1 M NaOCH3 / 1.) DMF, 120 deg C, 12 h, 2.) MeOH View Scheme