1: 92 percent / methanol / 48 h / 20 °C 2: 0.05N H2SO4 / H2O / 5 h / 50 °C 3: 74 percent / triethylamine / -15 deg C, 5h, then 50 deg C, 14 h View Scheme

1: 95 percent / n-butyllithium / hexane; methanol / 4 h / Heating 2: 95 percent / 0.05N H2SO4 / H2O / 5 h / 50 °C 3: triethylamine / methanol / 1 h / 20 °C View Scheme