Reaction Steps
Into a 2.0 L, 4-Necked, RB flask equipped with two addition funnels, thermometer socket and a pH meter was charged 800 mL of DM water. The contents were kept under nitrogen atmosphere. 2-Hydroxy-4-(methoxymethoxy)-3-methylbenzaldehyde (100 g) was added to the reaction mass under stirring. Aqueous sodium hydroxide (0.5 mL, dissolve 24.6 g of sodium hydroxide in 82.0 mL of DM Water) was added to the reaction mass to get a pH of 7.0-8.0. Reaction mass was heated to 40-45° C. Simultaneous addition of aqueous sodium hydroxide and hydrogen peroxide to, the reaction was started using two addition funnels. During the addition pH of the reaction mass was maintained at 7.8-8.4 and the temperature at 40-45° C. After the completion of addition, maintained the reaction mass at 40-45° C. for 4.0 h. The reaction mass was cooled to 25-30° C. and extracted with 3×500 mL of ethyl acetate. Combined organic layer was washed with 500 mL of saturated NaCl solution, treated with 20 g of activated carbon, dried with sodium sulphate, and distilled of solvent under vacuum to get 90 g of crude 4-(methoxymethoxy)-3-methylbenzene-1,2-diol as thick syrup. HPLC purity of sample is about 85%. The material is directly used in next stage. A small sample is purified by column chromatography for characterization purpose. M.R.: 60.5-61.5° C. IR (neat): 3487, 3200, 2969, 2942, 1630, 1621, 1488, 1443, 1405, 1378, 1307, 1290, 1242, 1150, 1086, 1042, 1007, 987, 904, 881, 806, 735, 660, 606 cm−1. 1H-NMR (CDCl3, 400 MHz): δ 8.79 (s, 1H, exchangeable with D2O, OH), 8.19 (s, 1H, exchangeable with D2O, OH), 6.51 (d, J=8.4 Hz, 1H, Ar. H), 6.34 (d, J=8.8 Hz, 1H, Ar. H), 5.02 (s, 2H, OCH2O), 3.36 (s, 3H, OMe), 2.01 (s, 3H, ArCH3). 13C-NMR (CDCl3, 100 MHz): δ 148.45 (C-4), 143.92 (C-2), 139.95 (C-1), 114.64 (C-3), 111.77 (C-6), 105.60 (C-5), 95.16 (OCH2O), 55.49 (OMe), 9.17 (ArCH3). Mass (EI-MS): 184.46 (M), 183.3 (M−1)
