1: LiHMDS / THF 1) 1 h, -78 deg C 2) 2 h, -10 deg C 3) 1 h, -78 deg C 4) 16 h, r.t. 2: 79 percent / 0.5percent H2SO4 / acetic acid / 1 h / 95 - 100 °C View Scheme

1: LiHMDS / THF 1) 1 h, -78 deg C 2) 2 h, -10 deg C 3) 1 h, -78 deg C 4) 16 h, r.t. 2: 78 percent / 0.5percent H2SO4 / acetic acid / 1 h / 95 - 100 °C View Scheme