in isopropyl alcohol T=40 - 45°C;

1: 94 percent / K2CO3 / dimethylformamide / 2.5 h / Ambient temperature 2: 82 percent / DMAP / tetrahydrofuran / 1) ice-salt cooling, 30 min, 2) r.t. 3: 40 percent / propan-2-ol / 40 - 45 °C View Scheme

1: 82 percent / DMAP / tetrahydrofuran / 1) ice-salt cooling, 30 min, 2) r.t. 2: 40 percent / propan-2-ol / 40 - 45 °C View Scheme

1: 94 percent / K2CO3 / dimethylformamide / 2.5 h / Ambient temperature 2: 82 percent / DMAP / tetrahydrofuran / 1) ice-salt cooling, 30 min, 2) r.t. 3: 40 percent / propan-2-ol / 40 - 45 °C View Scheme