1: 85 percent / pyridine; ethanol / 22 h / Ambient temperature 2: 80 percent / KOH / methanol; H2O / 18 h / Heating 3: 86.2 percent / triethylamine / CH2Cl2 / 0.5 h / cooling 4: 1) 57percent NaH / 1) 1h, DME; 2) DME, 16h, reflux 5: KOH / methanol; H2O / 18 h / Heating 6: various solvent(s) / Heating 7: 2N HCl / acetone / 5 h / Heating 8: 80.6 percent / p-toluenesulfonic acid / 5 h / Heating View Scheme

acetic anhydride in pyridine; methanol; acetic acid

in methanol; acetic acid

1: 85 percent / pyridine; ethanol / 22 h / Ambient temperature 2: 80 percent / KOH / methanol; H2O / 18 h / Heating 3: 86.2 percent / triethylamine / CH2Cl2 / 0.5 h / cooling 4: 1) 57percent NaH / 1) 1h, DME; 2) DME, 16h, reflux 5: KOH / methanol; H2O / 18 h / Heating 6: various solvent(s) / Heating 7: 2N HCl / acetone / 5 h / Heating 8: 87 percent / p-toluenesulfonic acid / 17 h / Heating View Scheme

1: 85 percent / pyridine; ethanol / 22 h / Ambient temperature 2: 80 percent / KOH / methanol; H2O / 18 h / Heating 3: 86.2 percent / triethylamine / CH2Cl2 / 0.5 h / cooling 4: 1) 57percent NaH / 1) 1h, DME; 2) DME, 16h, reflux 5: KOH / methanol; H2O / 18 h / Heating 6: various solvent(s) / Heating 7: 2N HCl / acetone / 5 h / Heating 8: 87 percent / p-toluenesulfonic acid / 17 h / Heating 9: 95.8 percent / pyridine; ethanol / 22 h / Ambient temperature 10: 84.6 percent / 25percent (i-Bu)2AlH / benzene; hexane / 1.5 h / 0 - 5 °C 11: 77.9 percent / triethylamine / CH2Cl2 / 0.5 h 12: 57percent NaH / 1,2-dimethoxy-ethane / 18 h / Heating 13: 64.2 percent / KOH / H2O; methanol / 18 h / Heating 14: 84 percent / various solvent(s) / Heating 15: 90 percent / 2N HCl / acetone / 5 h / Heating 16: 94.9 percent / p-toluenesulfonic acid / 17 h / Heating View Scheme

Yield given. Multistep reaction;

bromine in tetrachloromethane; N,N-dimethyl acetamide

sulfuryl dichloride in tetrachloromethane; toluene

(i) SO2Cl2, CCl4, (ii) collidine, toluene; Multistep reaction;

1: (i) K2CO3, DMF, (ii) aq. H2SO4, AcOH, (iii) Ac2O 2: (i) SO2Cl2, CCl4, (ii) collidine, toluene View Scheme