To a solution of (S)-2-(2-Bromo-6-methyl-4-nitrophenyl)-2-tert-butoxyethyl pivalate (9 g, 0.022 mol) in EtOH (50 mL) and EtOAc (50 mL) was added Pt/C (1.4 g), and the reaction was fitted with a balloon of H2. The reaction mixture was stirred at room temperature for 3 h. TLC showed the reaction was complete. The reaction mixture was filtered over Celite. The filtrate was concentrated in vacuo to give (S)-2-(4-amino-2-bromo-6-methylphenyl)-2-tert-butoxyethyl pivalate (7 g, 82%) as brown oil, which was immediately used for next step without further purification. 1H-NMR: 400 MHz, (CDCl3) δ: 6.70 (s, 1H), 6.40 (s, 1H), 5.38 (app. s, broad, 1H), 4.22 (app. s, broad, 1H), 4.05 (app. s, broad, 1H), 3.60 (app. s, broad, 2H), 2.47 (s, 3H), 1.17 (s, 9H), 1.13 (s, 9H).
