tert.-butyl lithium in hexane a. -78 deg C, 1h b. 0 deg 2h, c. room temperature, 18h;

1: 85 percent / NaH / dimethylformamide / 1. 0 deg C 2. room temperature, 1h 2: 43 percent / t-BuLi / hexane / a. -78 deg, 1h b. 0 deg, 2h c. 18f, room temperature View Scheme