hydrogen; palladium on activated charcoal in ethanol P=2587.7 Torr; 48 h; Yield given;

1: 79 percent / tetrabutylammonium bromide, CuBr2, molecular sieve 4A / 1,2-dichloro-ethane; dimethylformamide / 16 h / Ambient temperature 2: 70 percent / 60percent aq. acetic acid / 1.5 h / 50 °C 3: 4-toluenesulfonic acid monohydrate / benzene / 1.5 h / Ambient temperature 4: 80percent aq. acetic acid / 1 h / Ambient temperature 5: 79 percent / SO3-pyridine complex / dimethylformamide / 1.5 h / Ambient temperature 6: 0.1 M sodium methoxide / methanol / 16 h / Ambient temperature 7: H2 / 10percent Pd-C / aq. ethanol / 48 h / 2587.7 Torr View Scheme

1: 4-toluenesulfonic acid monohydrate / benzene / 1.5 h / Ambient temperature 2: 80percent aq. acetic acid / 1 h / Ambient temperature 3: 79 percent / SO3-pyridine complex / dimethylformamide / 1.5 h / Ambient temperature 4: 0.1 M sodium methoxide / methanol / 16 h / Ambient temperature 5: H2 / 10percent Pd-C / aq. ethanol / 48 h / 2587.7 Torr View Scheme