Dimethyl Sulfide → Tert-butyl 4,4-difluoro-2-(hydroxymethyl)pyrrolidine-1-carboxylate

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of N-(tert-butoxycarbonyl) 4,4-difluoroproline (3.00 g, 11.9 mmol) in THF (20 ml) was added BH3.DMS (1. 1 ml, 11.9 mmol) at room temperature. The mixture was heated at reflux for 2 h. After cooling to room temperature, the mixture was concntrated in vacuo. The residue was quenched by the addition of H2O (100 ml) and extracted with CHCl3 (2×200 ml). The combined extracts were dried over MgSO4 and evaporated. The residue was chromatographed on silica gel with CHCl3-EtOAc (4:1) as eluent to give 1-(tert-butoxycarbonyl)-4,4-difluoro-2-pyrrolidinylmethanol (2.11 g, 75%) as a colorless oil. 1H-NMR (CDCl3) δ 1.48 (s, 9 H), 2.04–2.55 (m, 2 H), 3.59–4.17 (m, 5 H).

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