4-Methyl-2-nitroaniline → 4-methyl-N-((2-(methylthio)benzo[d]thiazol-6-yl)methyl)-2-nitroaniline

Participants

Reaction Steps

To a stirred mixture of 4-methyl-2-nitroaniline (1 g, 6.5 mmol) in TFA (15 mL) at 0 to 5° C. was added portionwise sodium triacetoxyborohydride (2.78 g, 13.2 mmol) and the mixture was stirred for 10 min. To the reaction mixture was added portionwise 2-(methylthio)benzo[d]thiazole-6-carbaldehyde (1.44 g, 6.9 mmol) from Step 1 of Example 100. After stirring at rt for 4 h, the mixture was poured into ice-water and extracted with EtOAc (100 mL×3). The combined organic layers were washed with saturated aq NaHCO3 (100 mL×2) and brine (100 mL). The organic layer was separated, dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was purified by silica gel flash chromatography eluting with 3% EtOAc in petroleum ether to afford 4-methyl-N-((2-(methylthio)benzo[d]thiazol-6-yl)methyl)-2-nitroaniline (0.93 g, 41%) as a yellow solid. 1H NMR (300 MHz, CDCl3) δ 8.37 (br s, 1H), 8.01 (s, 1H), 7.83 (d, J=8.4 Hz, 1H), 7.71 (s, 1H), 7.38 (dd, J=8.4, 2.4 Hz, 1H), 7.19 (dd, J=8.7, 2.1 Hz, 1H), 8.71 (d, J=8.7 Hz, 1H), 4.83 (d, J=6.0 Hz, 2H), 2.83 (s, 3H), 2.25 (s, 3H); LCMS (ESI) m/z 346 (M+H)+.

Provenance & Evidence