benzotriazol-1-ol; triethylamine; dicyclohexyl-carbodiimide in N,N-dimethyl-formamide 16 h;

4-methyl-morpholine in N,N-dimethyl-formamide T=-20°C; 2 h; Yield given;

1: Et3N / tetrahydrofuran / 0.17 h / -15 °C 2: Et3N / tetrahydrofuran; dimethylformamide / 0 - 20 °C View Scheme

triethylamine in tetrahydrofuran; N,N-dimethyl-formamide T=0 - 20°C; Yield given;

1: 87 percent / NH3 / methanol / 20 h / Ambient temperature 2: 90 percent / 1 N HCl / acetic acid / 0.5 h / Ambient temperature 3: N-methylmorpholine / dimethylformamide / 2 h / -20 °C 4: 95 percent / 1 N HCl / acetic acid / 0.5 h / Ambient temperature 5: N-methylmorpholine, hexamethylphosphoric acid triamide / dimethylformamide / 2 h / -20 °C 6: 89 percent / 1 N HCl / acetic acid / 0.5 h / Ambient temperature 7: N-methylmorpholine / dimethylformamide / 2 h / -20 °C 8: 95 percent / 1 N HCl / acetic acid / 0.5 h / Ambient temperature 9: N-methylmorpholine / dimethylformamide / 2 h / -20 °C View Scheme

sodium hydroxide in water; acetone 1.5 h;

1: 77.7 percent / HCl, thioanisole / ethyl acetate / 0.5 h / Ambient temperature 2: 1.) N-methylmorpholine, isobutyl chloroformate / 1.) DMF, -20 deg C, 5 min, 2.) 2 h 3: 92 percent / NH3 / methanol / 48 h / Ambient temperature 4: 93 percent / HCl, thioanisole / ethyl acetate / 0.5 h / Ambient temperature View Scheme