1: 75 percent / 3,3,6,9,9-pentamethyl-2,10-diazabicyclo<4.4.0>-1-decene / CH2Cl2 2: CsF/2-bromopyridiniumtetrafluoroborate / CH2Cl2 3: Bu4NF / tetrahydrofuran / 0.5 h / 0 °C 4: 50 percent / 1.) 2,4,6-trichlorobenzoyl chloride (TCBACl), NEt3; 2.) 4-(dimethylamino)pyridine (DMAP) / 1.) THF; 2.) PhCH3, 110 deg C 5: pyridinium p-toluenesulfonate (PPTS) / methanol / 50 °C View Scheme

PMDBD in dichloromethane