Sodium Carbonate → tert-butyl N-(4-chloro-3-(hydroxymethyl)phenyl)carbamate

Beteiligte Stoffe

Reaktionsschritte

To a solution of (5-amino-2-chlorophenyl)methanol (Aldrich, 500 mg, 3.17 mmol) in a mixture of dioxane (7.5 mL), water (7.5 mL) was added sodium carbonate (336 mg, 3.17 mmol) previously dissolved in 4 mL of water. Solution was stirred and cooled in an ice bath. Boc-anhydride (Aldrich, 692 mg, 3.17 mmol) was added in one portion, and stirring was continued at room temperature for 3 h. Dioxane was removed in vacuo conditions and the aqueous layer chilled, covered with a layer of ethyl acetate, and acidified to pH 4 with dilute KHSO4 (10%, aq) (ALDRICH). This was followed by extraction (EtOAc) and purification by chromatographic column 25 g cartridge (ISOLUTE silice) using Hex/EtOAc 100/0 to 50/50, giving 1,1-dimethylethyl [4-chloro-3-(hydroxymethyl)phenyl]carbamate (560 mg, 2.17 mmol, 68%). 1H NMR (300 MHz, DMSO-d6) δ ppm: 9.46 (br s, 1H), 7.72 (s, 1H), 7.21-7.32 (m, 2H), 5.35 (t, 1H), 4.48 (d, 2H), 1.47 (s, 9H).

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