1: 4 h / 100 °C 2: MeSO3H / 5 h / 100 °C View Scheme

1: 58.7 g / 5 h / 100 °C 2: 95 percent / MeSO3H / 5 h / 100 °C View Scheme

1: 4 h / 100 °C 2: MeSO3H / 5 h / 100 °C 3: 99 percent / N-bromosuccinimide / CH2Cl2; methanol / 7 h / -5 °C 4: Red-Al / toluene; CH2Cl2 / 1 h / 50 °C 5: 13.5 g / i-Pr2NEt / CH2Cl2 / 3 h / 0 °C View Scheme

1: 58.7 g / 5 h / 100 °C 2: 95 percent / MeSO3H / 5 h / 100 °C 3: 86 percent / N-bromosuccinimide / CH2Cl2; methanol / 7 h / -5 °C 4: 81 percent / Red-Al / toluene / 1 h / 50 °C 5: 17.3 g / i-Pr2NEt / CH2Cl2 / 3 h / 0 °C View Scheme