1: CH3COOH / ethanol / 2 h / 40 °C 2: 2.) DBU / 1.) CH2Cl2, -30 deg C, 15 min, 2.) 0 deg C to r.t., 1 h 3: CH2O / tetrahydrofuran; H2O / 1 h / Ambient temperature 4: NaBH4 / methanol / 0.5 h / 0 °C 5: 2 N HCl / 0.5 h / Ambient temperature View Scheme

1: 80 percent / Li / tetrahydrofuran / 1.) 10-15 deg C, 2.) r.t., 1 h 2: 80 percent / PBr3, pyridine / toluene / 1 h / -10 °C 3: 1.) DBU, 2.) 1 M aq. HCl / 1.) toluene, reflux, 5 h, 2.) THF, 25 deg C, 5 h View Scheme

1: 80 percent / PBr3, pyridine / toluene / 1 h / -10 °C 2: 1.) DBU, 2.) 1 M aq. HCl / 1.) toluene, reflux, 5 h, 2.) THF, 25 deg C, 5 h View Scheme

hydrogenchloride; 1,8-diazabicyclo[5.4.0]undec-7-ene 1.) toluene, reflux, 5 h, 2.) THF, 25 deg C, 5 h; Yield given. Multistep reaction. Yields of byproduct given;

in water HeatingpH=1;

pyridine; ozone; triphenylphosphine 1.) CH2Cl2, -78 deg C, 0.5 h; 2.) CH2Cl2, r.t., 1 h; Yield given. Multistep reaction;

3-chloro-benzenecarboperoxoic acid in dichloromethane T=0°C; 4 h;