18-crown-6 ether; potassium tert-butylate in tetrahydrofuran T=0 - 20°C;

1: 86 percent / NaHMDS / tetrahydrofuran; toluene / 0.25 h 2: 58 percent / potassium t-butoxide; 18-crown-6 / tetrahydrofuran / 0 - 20 °C View Scheme

1: 78 percent / tetrahydrofuran / cooling 2: 95 percent / oxalyl chloride; DMSO / CH2Cl2 / 3 h / -60 °C 3: 86 percent / NaHMDS / tetrahydrofuran; toluene / 0.25 h 4: 58 percent / potassium t-butoxide; 18-crown-6 / tetrahydrofuran / 0 - 20 °C View Scheme

1: 95 percent / oxalyl chloride; DMSO / CH2Cl2 / 3 h / -60 °C 2: 86 percent / NaHMDS / tetrahydrofuran; toluene / 0.25 h 3: 58 percent / potassium t-butoxide; 18-crown-6 / tetrahydrofuran / 0 - 20 °C View Scheme

18-crown-6 ether in tetrahydrofuran

1: C28H25NO2 With PhF-H; sodium hydride in tetrahydrofuran 0.5 h; 2: benzyl bromide in tetrahydrofuran 24 h; Further stages.;