Multi-step reaction with 9 steps
1: 1) 5 M HCl, 2) pyridine / 1) dioxane, 90 deg C, 4 h, 2) room temperature, 16 h
2: AcOH, Zn / 1 h / Ambient temperature
3: HCl / dioxane
4: N-methylmorpholine / CH2Cl2 / 1 h
5: 88 percent / MeONa / methanol / 0.33 h / Ambient temperature
6: 82 percent / p-TsOH*H2O / dimethylformamide / 5 h / Ambient temperature
7: 71 percent / pyridine, 4-dimethylaminopyridine / CH2Cl2 / 4 h / Ambient temperature
8: 4-dimethylaminopyridine, pyridine / CH2Cl2 / 1) 0 deg C, 30 min, 2) room temperature, 30 min
9: 90percent AcOH / 0.67 h / 90 °C
With
4-methyl-morpholine; pyridine; hydrogenchloride; dmap; sodium methylate; toluene-4-sulfonic acid; acetic acid; zinc;
In
1,4-dioxane; methanol; dichloromethane; N,N-dimethyl-formamide;
DOI:10.1248/cpb.38.3366