1: With ethylenediaminetetraacetic acid trisodium salt; oxygen; Mn(CH3COO)2*4H2O; ascorbic acid powder in water Udenfriend reaction; pH=4; 2: With iron sulphate heptahydrate; ethylenediaminetetraacetic acid trisodium salt; oxygen in water T=45°C; Udenfriend reaction; 2 h;

1: Na2S2O4, KOH / ethanol / 8 h / Heating 2: (i) NaH, xylene, (ii) /BRN= 605294/ 3: aq. HCl / 1 h / Heating View Scheme

hydrogenchloride 1 h; Heating;

1: (i) NaH, xylene, (ii) /BRN= 605294/ 2: aq. HCl / 1 h / Heating View Scheme

(i) NaH, DMSO, (ii) /BRN= 605294/, (iii) HCl, MeOH; Multistep reaction;