4,4'-(1,4-Butanediyl)dioxydianiline

14467-68-6

6245-50-7

1,4-bis(4-nitrophenoxy)butane (15, 0.97 g, 2.92 mmol) was used as feedstock and dissolved in dioxane (60 mL). The solution was passed through a Thalesnano H-cube TM continuous flow hydrogenation reactor equipped with a 30 mm Raney nickel catalyst (flow rate 0.5 mL/min) under 100% H2 atmosphere, 50 bar pressure, and 50°C. The reaction was carried out by thin layer chromatography (TLC). The reaction progress was monitored by thin layer chromatography (TLC) (unfolding agent ratio 50:50 ethyl acetate:hexane, Rf = 0.12). After complete consumption of the feedstock, the reaction mixture was concentrated under vacuum to afford the yellow solid product 4,4'-(1,4-butanedioxy)diphenylamine (0.98 g, 98% yield) with a melting point of 128-130 °C. The structure of the product was determined by 1H NMR (400 MHz, CD3OD) δ 6.87-6.58 (m, 8H), 4.12-3.80 (bm, 4H), 1.98-1.84 (bm, 4H); 13C NMR (101 MHz, CD3OD) δ 153.8,141.4,118.3,116.6,69.4,27.3; and confirmed by LRMS (ESI+) m/z 273 ([M+H]+, 100%).