2-Methyl-6-cyano- phenol

51673-93-9

13589-71-4

Salicylaldehyde (1A) (28.86 g, 1 eq.) was used as starting material and dissolved in DMSO (200 ml) to form an orange solution. Subsequently, hydroxylamine hydrochloride (29.31 g, 2.2 eq.) was added and the reaction mixture was stirred at room temperature for 20 min and the solution changed to yellow color. The reaction system was heated to 100 °C and maintained at this temperature for 6 hours and then cooled. After completion of the reaction, the mixture was quenched by pouring into water (300 ml) and extracted with ether (5 x 100 ml). The organic phases were combined, washed with saturated saline (2 x 50 ml), dried over anhydrous magnesium sulfate and concentrated to give a reddish brown solid (30.53 g). Semi-pure product suitable for subsequent reaction was obtained by extracting impurities from the crude product in refluxing heptane (100 ml), cooling and grinding with cold heptane. Further purification by fast column chromatography (silica gel as stationary phase, eluent ethyl acetate/hexane=1:9, Rf=0.32) afforded the pure product 2-hydroxy-3-methylbenzonitrile as an orange-red solid (20.58 g, 73% yield). The structure of the product was confirmed by IR, MS, 1H NMR, 13C NMR and elemental analysis.IR (NaCl, paraffin paste): 3301.5 cm-1 (ArOH), 2233.8 cm-1 (CN); MS (CI+, NH3): m/z=151.1 (M+NH4+, 100%); 1H NMR (400 MHz, CDCl3) δ: 7.35 (1H, t, J=1.0 Hz, H-4), 7.33 (1H, t, J=1.0 Hz, H-6), 6.90 (1H, t, J=7.7 Hz, H-5), 5.93 (1H, s, OH), 2.29 (3H, s, CH3); 13C NMR (100 MHz, CDCl3) δ: 157.4 (C- OH), 136.4 (C-4), 130.5 (C-6), 126.6 (C-3), 121.4 (C-5), 117.2 (C≡N), 99.2 (C-1), 16.3 (CH3); Elemental analysis (C12H16O2) Measured values: C 72.35%, H 5.28%, N 10.39%; Theoretical values: C 72.16%, H 5.30%, N 10.52%.