4-Nitronaphthalene-1,8-dicarboxylic anhydride synthesis

Yield: 74%

Reaction Conditions:

with sodium dichromate in acetic acid at 65 - 100; for 8.5 h;

Steps:

3 2.3 Synthesis of 4-Nitro-1, 8-naphthalic anhydride
5-Nitroacenaphthene (24.87 g, 0.125 mol) was dissolved in 248.75 mL of hot acetic acid, 158.5 g of sodium dichromate (Na₂Cr₂O₇·2H₂O) was added for 3 h at 65-70 °C. This was warmed gradually to 98-100 °C for 30 min and further refluxed for 5 h. The contents were washed out with 0.6 L of hot water, cooled, filtered and the solid was washed with dilute HCl. It was further boiled for 30 min with 200 mL of 5% Na₂CO₃ solution for 30 min, filtered, the filtrate was acidified and the separated crystals dried at 120 °C for 4 h to obtain 4-nitro-1,8-naphthalic anhydride, which was recrystallised from HNO₃ (d = 1.40 g/mL) to afford colourless needles [12]. Yield = 74%; Mp: 231-232 °C; FT-IR (KBr, cm^-1) 3078, 2914 2849, 1789, 1756, 1624, 1526; ¹H NMR (300 MHz, DMSO-d₆): δ (ppm) 8.09 (1H, t, J = 7.8 Hz, 3-H), 8.54 (1H, d, J = 7.9 Hz, 8-H), 8.61 (1H, s, 2-H), 8.64 (1H, d, J = 7.5 Hz, 9-H), 8.73 (1H, dd, J = 8.2, 8.7 Hz, 4-H); ¹³C NMR (75 MHz, DMSO-d₆): δ (ppm) 120.1, 122.6, 124.0, 124.3, 129.8, 130.3, 130.6, 131.1, 133.2, 149.5, 159.4, 160.0; Anal. Calcd for C₁₂H₅NO₅: C, 59.27; H, 2.07; N, 5.76%; found C, 59.17; H, 2.02; N, 5.75%.

References:

Ameuru, Umar Salami;Yakubu, Mohammed Kabir;Bello, Kasali Ademola;Nkeonye, Peter Obinna;Halimehjani, Azim Ziyaei [Dyes and Pigments,2018,vol. 157,p. 190 - 197]