4-HYDROXY-5-NITROBENZENE-1,3-DICARBALDEHYDE synthesis

Yield:70310-96-2 91%

Reaction Conditions:

with sulfuric acid;nitric acid at -5; for 1 h;

Steps:

Synthesis of 4-hydroxy-5-nitroisophthalaldehyde(2b)

Step 2: 1 g (6.6 mmol) of5-formyl-2-hydroxybenzaldehyde was added in small portionsto a mixture of nitric acid (1 mL, 68%) and concentratedsulfuric acid (2 mL) at - 5 °C, and the mixture wasstirred for 1 h. The reaction mixture was poured on 100 gof crushed ice. The yellow solid precipitate formed was filteredoff and washed with cold distilled water. The crudeproduct was recrystallized in acetone/water 50:50 (v/v).1.18 g of 4-hydroxy-5-nitroisophthalaldehyde (yield, 91%)was obtained. mp, 125-127 °C; 1H-NMR (300 MHz, CDCl3,25 °C, TMS) δ (ppm): 8.64 (s, 1H), 8.89 (s, 1H), 10.05 (s,1H, -CHO), 10.47 (s, 1H, -CHO), 11.97 (s, 1H, OH). 13CNMR(75 MHz, CDCl3,25 °C, TMS) δ (ppm): 125.68,128.43, 131.92, 135.91, 137.27, 159.90, 187.71, 189.02.FT-IR (KBr), ν (cm-1): 3062, 2861, 1695, 1664, 1608, 1531,1436, 1355, 1292, 1247, 1174, 1159, 983, 935, 821, 767,732, 696, 646; Anal. Calcd. for C8H5NO5:C, 48.94; H, 2.56;N, 7.14; Found: C, 49.02; H, 2.61; N, 7.20.

References:

Sepehr, Zeinalabedin;Nasr-Isfahani, Hossein;Mahdavian, Ali Reza;Amin, Amir Hossein [Journal of the Iranian Chemical Society,2021,vol. 18,# 11,p. 3061 - 3067]