2,6-dimethoxybenzonitrile

Conditions: temp:210.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Another potential method utilizes pyridine hydrochloride in place of the boron tribromide. Into a 500 mL 3-neck round bottom flask equipped with stir bar, nitrogen inlet and condenser was charged 2,6-dimethoxybenzonitrile (15.0 g, 91.9 mmol), followed by pyridine hydrochloride (150 g). The mixture was heated to 210° C. for 2 hours and allowed to cool to room temperature. Water was then added to the flask to dissolve the solidified mixture. The aqueous layer was then extracted with ethyl acetate (150 mL) 3 times. The combined organic layer was dried under anhydrous sodium sulfate, and the solvent was removed to yield 7.44 g (60.0%) of a light pink solid, m.p.: 202.8-204.8° C. 1H-NMR (DMSO-d6): 6.39-6.41 (d, 2H, Ar—H), 7.20-7.24 (t, 1H), 10.78 (s, 2H, Ar—O—H). Into a 500 mL 3-neck round bottom flask equipped to cool to room temperature to dissolve the solidified mixture The aqueous layer was then extracted with ethyl acetate (150 mL) 3 times The combined organic layer was dried under anhydrous sodium sulfate the solvent was removed

Conditions: temp:210.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Another potential method utilizes pyridine hydrochloride in place of the boron tribromide. Into a 500 mL 3-neck round bottom flask equipped with stir bar, nitrogen inlet and condenser was charged 2,6-dimethoxybenzonitrile (15.0 g, 91.9 mmol), followed by pyridine hydrochloride (150 g). The mixture was heated to 210° C. for 2 hours and allowed to cool to room temperature. Water was then added to the flask to dissolve the solidified mixture. The aqueous layer was then extracted with ethyl acetate (150 mL) 3 times. The combined organic layer was dried under anhydrous sodium sulfate, and the solvent was removed to yield 7.44 g (60.0%) of a light pink solid, m.p.: 202.8-204.8° C. 1H-NMR (DMSO-d6): 6.39-6.41 (d, 2H, Ar—H), 7.20-7.24 (t, 1H), 10.78 (s, 2H, Ar—O—H). Into a 500 mL 3-neck round bottom flask equipped to cool to room temperature to dissolve the solidified mixture The aqueous layer was then extracted with ethyl acetate (150 mL) 3 times The combined organic layer was dried under anhydrous sodium sulfate the solvent was removed

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred suspension of 2,6-dimethoxy-benzonitrile (0.82 g, 5 mmol) and N-methylhydroxylamine hydrochloride (1.66 g, 20 mmol) in 1:1 water/ethanol (20 mL) was added sodium carbonate (1.05 g, 10 mmol) in small portions and the resulting mixture stirred at 80° C. for 24 h. The reaction mixture was concentrated and the residue was re-dissolved into 1:1 water:ethanol (25 mL). To this solution was added diethyl acetylenedicarboxylate (0.96 mL, 6 mmol) and the resulting mixture stirred for 30 min at room temperature. The reaction mixture was then taken up in ethyl acetate (100 mL), washed successively with water and brine (50 mL each), dried (Na2SO4), filtered and concentrated to give a yellow oil. The crude product was purified on silica gel column (3:7 to 1:1 ethyl acetate/hexanes) to afford the title compound as a viscous yellow (1.5795 g, 83% yield). 1HNMR (500 MHz, CDCl3) δ: 7.32 (1H, t, J=8.24 Hz), 6.55 (2H, d, J=8.24 Hz), 4.38–4.24 (2H, m), 4.20–4.14 (2H, m), 3.80 (6H, s), 3.48 (1H, d, J=16.48 Hz), 3.03 (1H, d, J=16.48 Hz), 3.02 (3H, s), 1.33 (3H, t, J=7.02 Hz), 1.26 (3H, 7.02 Hz). HRMS (ESI) calcd for C18H25N2O7S (M+H): 381.1662; found: 381.1656. The reaction mixture was concentrated the residue was re-dissolved into 1:1 water the resulting mixture stirred for 30 min at room temperature washed successively with water and brine (50 mL each) dried (Na2SO4) filtered concentrated to give a yellow oil The crude product was purified on silica gel column (3:7 to 1:1 ethyl acetate/hexanes)