lithium diisopropyl amide in tetrahydrofuran; cyclohexane 5 h; Heating;

Multi-step reaction with 3 steps 1: cyclohexane; diethyl ether; toluene / 1) 0 deg C, 0.5 h, 2) r.t., 1.5 h2: 94 percent / CHCl3 / 360 h / Heating3: 1) 1-chloroethyl chloroformate, 2) MeOH / 1) 1,2-dichloroethane, a) 0 deg C, 15 min, b) reflux, 2 h, 2) reflux, 4 h