Multi-step reaction with 8 steps
1: 99 percent / triethylamine / dimethylformamide / 0 deg C and than r.t. overnight
2: 76 percent / p-toluenesulfonic acid monohydrate / toluene / 4 h / Heating; azeotropic removal of water
3: triethylamine, phosgene / acetonitrile; toluene / 2 h / 0 °C
4: concd. NH4OH / tetrahydrofuran / Ambient temperature
5: 1.) dicyclohexylborane, 2.) H2O2 / 1.) THF, a) 0 deg C, 5 min, b) r.t., 1.5 h, 2.) pH 7 phosphate buffer, ethanol, r.t., overnight
6: 1.) triethylamine, pyridine/SO3, 2.) triethylsilane, trifluoroacetic acid / 1.) DMSO, 20 min, 2.) methylene dichloride, r.t., 18 h
7: saturated aqueous Ba(OH)2 / methanol / 18 h / Ambient temperature
8: 1-hydroxybenzotriazole hydrate, 1-ethyl-3-<(3-dimethylamino)propyl>carbodiimide hydrochloride / dimethylformamide / 0 deg C up to r.t., r.t. overnight
With
pyridine; triethylsilane; phosgene; barium dihydroxide; ammonium hydroxide; bis(cyclohexanyl)borane; sulfur trioxide; dihydrogen peroxide; toluene-4-sulfonic acid; 1-hydroxybenzotriazol-hydrate; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine; trifluoroacetic acid;
In
tetrahydrofuran; methanol; N,N-dimethyl-formamide; toluene; acetonitrile;
DOI:10.1021/jo00012a022