Hydrochloric Acid → 5-(tert-Butyl)-2-methoxy-3-nitroaniline

Participants

Reaction Steps

Under N2 was charged 4-tert-butyl-2,6-dinitroanisole (620 g, 2.439 mol), IMS (4774 mL) and 10% Pd/C (31.8 g). The reaction mixture was heated to reflux (78° C.) and 4-methyl-1-cyclohexene (500 mL, 4.159 mol) was added dropwise over 4.5 h. The reaction was stirred at reflux overnight, whereupon HPLC analysis indicated 72.13% product and 27.17% starting material. Further 4-methyl-1-cyclohexene (160 mL, 1.331 mol) was added dropwise over 3 h and the reaction was stirred at reflux for 72 h. HPLC analysis indicated 92.72% product and 0% starting material. The reaction was cooled to room temperature and the catalyst was removed via vacuum filtration and washed with IMS (500 mL). The solvents were concentrated to ca. 1200 mL to give a ratio of 1:4.45 product:ethanol (target 1:5). 2 M HCl (124 mL) was charged dropwise to the remainder while maintaining the temperature below 23° C. Water (3100 mL) was charged and the resulting suspension was stirred at room temperature for 1.5 h. The solid was collected via vacuum filtration and washed with water (2×1000 mL). The resulting orange needles were dried, under vacuum, at 40° C. overnight. Yield=475.2 g (86.9%). Purity >97% by 1H NMR. HPLC purity 98.8%. KF 0.36%.

Provenance & Evidence