1: 90 percent / N-bromosuccinimide (NBS), 48 percent HBr / CCl4 / 1 h / Heating 2: 88 percent / tributylzinnhydride, α,α'-azoisobutyronitrile / toluene / 2 h / 80 °C 3: 1.) tetraethyltitanate 2.) 2 N HCl / 1.) reflux, 8 h; 2.) CH2Cl2 + water View Scheme

lithium aluminium tetrahydride in tetrahydrofuran; diethyl ether 14 h; Ambient temperature;