2,2,6,6-tetramethylpiperidinyl-lithium in tetrahydrofuran; hexane T=0°C; 1 h; Inert atmosphere; chemoselective reaction;

1: 100 percent / sodium borohydride / methanol / 0.33 h / 0 °C 2: 82 percent / imidazole / CH2Cl2 / 4 h / Heating 3: 86 percent / sodium nitrite / dimethylsulfoxide; H2O / 65 °C View Scheme

1H-imidazole in N,N-dimethyl-formamide

1: 80 percent / imidazole / dimethylformamide / 12 h / Ambient temperature 2: 1.) Na2HPO4, NaOH, 2.) aq. potassium hydrogen persulfate / 1.) MeOH, 1 h, 2.) room temperature, 1 h View Scheme