1: 75 percent / bis(tetrabutylammonium)dichromate / CHCl3 / 0.17 h / Heating 2: 1) n-Butyllithium / 1) a) -78 deg C, b) room temperature, 1.5 h, 2) THF, a) - 78 deg C, 0.5 h, b) room temperature, 16 h View Scheme

1: 95 percent / N-bromosuccinimide, benzoyl peroxide / CCl4 / 6 h / Heating; Irradiation 2: 75 percent / bis(tetrabutylammonium)dichromate / CHCl3 / 0.17 h / Heating 3: 1) n-Butyllithium / 1) a) -78 deg C, b) room temperature, 1.5 h, 2) THF, a) - 78 deg C, 0.5 h, b) room temperature, 16 h View Scheme

n-butyllithium 1) a) -78 deg C, b) room temperature, 1.5 h, 2) THF, a) - 78 deg C, 0.5 h, b) room temperature, 16 h; Yield given. Multistep reaction;