[Synthesis]
The general procedure for the synthesis of 2,4-di-tert-butyl-5-nitrophenyl methyl carbonate and compound (CAS: 873055-56-2) from 2,4-di-tert-butyl-5-nitrophenol and 2,4-bis(tert-butyl)-6-nitrophenol was as follows. ester mixture (4.2 g, 12.9 mmol) was dissolved in methanol (65 mL) and potassium hydroxide (2.0 g, 36 mmol) was added. The reaction mixture was stirred at room temperature for 2 hours. Subsequently, the reaction mixture was acidified to pH 2-3 by addition of concentrated hydrochloric acid. the acidified mixture was partitioned between water and ether. The ether layer was separated, dried over magnesium sulfate, concentrated, and purified by column chromatography (0-5% ethyl acetate-hexane) to afford 2,4-di-tert-butyl-5-nitrophenol (1.31 g, two-step yield 29%) and 2,4-di-tert-butyl-6-nitrophenol.1H NMR (400 MHz, DMSO-d6) data for 2,4-di-tert-butyl-5-nitrophenol: δ 10.14 (s, 1H, OH), 7.34 (s, 1H), 6.83 (s, 1H), 1.36 (s, 9H), 1.30 (s, 9H).1H NMR (400 MHz, CDCl3) data of 2,4-di-tert-butyl-6-nitrophenol: δ 11.48 (s, 1H), 7.98 (d, J = 2.5Hz, 1H). 7.66 (d, J = 2.4 Hz, 1H), 1.47 (s, 9H), 1.34 (s, 9H). |