hydrogenchloride; acetic acid in tetrahydrofuran T=150°C; 0.35 h; Microwave irradiation;

dipyridinium dichromate in N,N-dimethyl-formamide Ambient temperature;

1: 1) n-butyllithium / 1) THF, -23 deg C, 1 h, 2) THF, HMPA, 2.1) -23 deg C, 30 min., 2.2) RT, 1.5 h 2: 91 percent / 37percent HCl / methanol / Ambient temperature 3: 86 percent / pyridinium dichromate / dimethylformamide / Ambient temperature View Scheme

1: 95 percent / phosphorus pentoxide / CH2Cl2 / Ambient temperature 2: 1) CH3Li*LiBr / 1) THF, RT, 3.5 h, 2) THF, HMPA, RT, 30 min 3: KF*2H2O / dimethylformamide / 0.5 h / Ambient temperature 4: 1) n-butyllithium / 1) THF, -23 deg C, 1 h, 2) THF, HMPA, 2.1) -23 deg C, 30 min., 2.2) RT, 1.5 h 5: 91 percent / 37percent HCl / methanol / Ambient temperature 6: 86 percent / pyridinium dichromate / dimethylformamide / Ambient temperature View Scheme

1: 1) CH3Li*LiBr / 1) THF, RT, 3.5 h, 2) THF, HMPA, RT, 30 min 2: KF*2H2O / dimethylformamide / 0.5 h / Ambient temperature 3: 1) n-butyllithium / 1) THF, -23 deg C, 1 h, 2) THF, HMPA, 2.1) -23 deg C, 30 min., 2.2) RT, 1.5 h 4: 91 percent / 37percent HCl / methanol / Ambient temperature 5: 86 percent / pyridinium dichromate / dimethylformamide / Ambient temperature View Scheme

1: 1) n-butyllithium / 1) THF, -23 deg C, 1 h, 2) THF, HMPA, 2.1) -23 deg C, 30 min., 2.2) RT, 1.5 h 2: 91 percent / 37percent HCl / methanol / Ambient temperature 3: 86 percent / pyridinium dichromate / dimethylformamide / Ambient temperature View Scheme

1: 91 percent / 37percent HCl / methanol / Ambient temperature 2: 86 percent / pyridinium dichromate / dimethylformamide / Ambient temperature View Scheme

potassium hydroxide; hydroxylamine hydrochloride; ethylamine; copper(l) chloride 2) methanol, ether, 15 min; Yield given. Multistep reaction;