1: pyridine / benzene / 2 h / O deg C to room temp. 2: H2O / 1.5 h / Heating 3: 2.) Ag2CO3 / 1.) toluene, 3 d, room temp., 2.) methanol, 1.5 h reflux View Scheme

1: KOH / tetrahydrofuran; dimethylsulfoxide / 2 h / Ambient temperature 2: pyridine / benzene / 2 h / O deg C to room temp. 3: H2O / 1.5 h / Heating 4: 2.) Ag2CO3 / 1.) toluene, 3 d, room temp., 2.) methanol, 1.5 h reflux View Scheme

2: 1.) trimethylsilyl triflate / 1.) CH2Cl2, 0 deg C, 2.) 0 deg C to room temp., 3h View Scheme

trimethylsilyl trifluoromethanesulfonate 1.) CH2Cl2, 0 deg C, 2.) 0 deg C to room temp., 3h; Yield given. Multistep reaction;

silver carbonate 1.) toluene, 3 d, room temp., 2.) methanol, 1.5 h reflux;