Multi-step reaction with 12 steps
1: TMSOTf / CH2Cl2 / Ambient temperature
2: KOH / ethanol / 0.5 h / 24 °C
3: p-TsOH*H2O / dimethylformamide / 16 h / 25 °C
4: 1.) Ph3P, 2.) H2O, 3.) DCC, DMAP, 4.) Et3N
5: 1.) HCl / 1.) dioxane, H2O, 55-60 deg C, 4 h, 2.) DMF, 55-60 deg C, 1.5 h
6: 56 percent / p-TsOH*H2O / dimethylformamide / 16 h / 25 °C
7: 96 percent / DCC, DMAP / CH2Cl2 / 16 h / 25 °C
8: 58 percent / aq. AcOH / 1 h / 70 - 75 °C
9: 97 percent / pyridine / CH2Cl2 / 0.5 h / 0 - 5 °C
10: 87 percent / DMAP / CH2Cl2 / 4 h / 24 °C
11: 1.) H2 / 1.) Pd/C / 1.) THF, 24 deg C, 10 h, 2.) 24 deg C, 16 h
12: 87 percent / DAST / CH2Cl2 / 3.5 h / 0 °C
With
pyridine; hydrogenchloride; dmap; potassium hydroxide; trimethylsilyl trifluoromethanesulfonate; water; hydrogen; toluene-4-sulfonic acid; acetic acid; triethylamine; dicyclohexyl-carbodiimide; triphenylphosphine; 4,4'-diaminostilbene-2,2'-disulfonic acid;
palladium on activated charcoal;
In
ethanol; dichloromethane; N,N-dimethyl-formamide;
DOI:10.1016/S0040-4020(97)10063-1