(2-methoxyacetyl) 2-methoxyacetate

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

Procedure: A mixture of methoxyacetic acid (360 g, 4 mol) and acetic anhydride (409 g, 4 mol) was heated with stirring in a 2 L 3-neck flask equipped with a bubble-plate distillation column and a fraction cutter. A mixture of acetic acid and acetic acid anhydride was distilled at atmospheric pressure until the internal temperature reached 164° C. The pressure was reduced and the product was collected at 65°-71° C. at 0.2 mmHg to give 229 g (71%) of pure title compound. A total of 34.8 kg of methoxyacetic acid was processed to give 26.1 kg (83%) of the anhydride (I). was heated equipped with a bubble-plate distillation column was distilled at atmospheric pressure until the internal temperature reached 164° C the product was collected at 65°-71° C. at 0.2 mmHg

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

Procedure: To a solution of methyl 2-(3,4-dimethoxy-phenyl)acetate SLA 28134 (3.36 g, 15.98 mmol) in methoxyacetic anhydride SMA 44010 (10.19 g, 62.85 mmol) at 0° C. in a 250 mL round-bottomed flask equipped with a magnetic stirrer was added dropwise HClO4 (ca. 70% solution in water, 1.64 mL, 18.98 mmol). The mixture was then stirred for 45 min at RT then diluted with Et2O (151 mL). The organic solution was removed to give a viscous residue that was suspended in H2O (30 mL) at 5° C. before dropwise addition of a conc. NH4OH solution (38 mL). After complete addition, the mixture was stirred overnight at RT and extracted with CH2Cl2 (50 mL) then with CH2Cl2:MeOH=95:5 (100 mL). The organic phase was combined, washed with brine (30 mL), dried over Na2SO4, filtered and concentrated at 40° C. under vacuum. Purification by column chromatography (SiO2, eluent CH2Cl2:MeOH=100:0 to 93:7) gave 6,7-dimethoxy-1-methoxymethyl-isoquinolin-3-ol SMA 44012 as a yellow solid (96 mg, 2% yield). The organic solution was removed to give a viscous residue that After complete addition the mixture was stirred overnight at RT extracted with CH2Cl2 (50 mL) washed with brine (30 mL) dried over Na2SO4 filtered concentrated at 40° C. under vacuum Purification by column chromatography (SiO2, eluent CH2Cl2:MeOH=100:0 to 93:7)

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

Procedure: A mixture of methoxyacetic acid (360 g, 4 mol) and acetic anhydride (409 g, 4 mol) was heated with stirring in a 2 L 3-neck flask equipped with a bubble-plate distillation column and a fraction cutter. A mixture of acetic acid and acetic acid anhydride was distilled at atmospheric pressure until the internal temperature reached 164° C. The pressure was reduced and the product was collected at 65°-71° C. at 0.2 mmHg to give 229 g (71%) of pure title compound. A total of 34.8 kg of methoxyacetic acid was processed to give 26.1 kg (83%) of the anhydride (I). was heated equipped with a bubble-plate distillation column was distilled at atmospheric pressure until the internal temperature reached 164° C the product was collected at 65°-71° C. at 0.2 mmHg

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

Procedure: A mixture of methoxyacetic acid (360 g, 4 mol) and acetic anhydride (409 g, 4 mol) was heated with stirring in a 2 L 3-neck flask equipped with a bubble-plate distillation column and a fraction cutter. A mixture of acetic acid and acetic acid anhydride was distilled at atmospheric pressure until the internal temperature reached 164° C. The pressure was reduced and the product was collected at 65°-71° C. at 0.2 mmHg to give 229 g (71%) of pure title compound. A total of 34.8 kg of methoxyacetic acid was processed to give 26.1 kg (83%) of the anhydride (I). was heated equipped with a bubble-plate distillation column was distilled at atmospheric pressure until the internal temperature reached 164° C the product was collected at 65°-71° C. at 0.2 mmHg