1: 81 percent / NaN3 / dimethylsulfoxide / 0.5 h / 60 - 70 °C 2: 40 percent / toluene / 4 h / 100 - 110 °C View Scheme

1: 53 percent / K2CO3, CuO / dimethylformamide / 1) reflux, 8 h, 2) r.t., overnight 2: 81 percent / NaN3 / dimethylsulfoxide / 0.5 h / 60 - 70 °C 3: 40 percent / toluene / 4 h / 100 - 110 °C View Scheme

(i) KOH, EtOH, (ii) NaOCl; Multistep reaction;