2,2,2-Trifluoroethanol → (2S,4R)-1-tert-Butyl 2-methyl 4-(4-(2,2,2-trifluoroethoxy)-2-(trifluoromethyl)phenylsulfonyl)pyrrolidine-1,2-dicarboxylate

Participants

Reaction Steps

Under an atmosphere of argon, (2S,4R)-1-tert-butyl 2-methyl 4-(4-fluoro-2-(trifluoromethyl)phenylsulfonyl)pyrrolidine-1,2-dicarboxylate ([prepared in analogy to General Procedure C, steps C1-C3, using 2-trifluoromethyl-4-fluorothiophenol in step C2] 0.79 g, 1.73 mmol, Eq: 1.00) was combined with N,N-dimethylacetamide (10 ml) to give a light yellow solution. 2,2,2-Trifluoroethanol (416 mg, 301 μl, 4.16 mmol, Eq: 2.4) and cesium carbonate (1.02 g, 3.12 mmol, Eq: 1.8) were added. The reaction mixture was stirred over night at RT. The crude reaction mixture was concentrated in vacuo. The residue was poured into HCl (0.5 M, 20 ml) and extracted with ethyl acetate. The organic layers were dried over Na2SO4 and concentrated in vacuo. The crude material was purified by flash chromatography (silica gel, 50 g, 0% to 40% ethyl acetate in heptane) to yield the title compound as a white foam (610 mg, 65.7%, MS (m/e)=536.1 [M+H+]).

Provenance & Evidence