1: methanol; sodium methylate / 3 h / 20 °C 2: zinc(II) chloride / 12 h / 20 °C 3: pyridine / 10 h / 20 °C 4: acetic acid / 3 h / 80 °C 5: boron trifluoride diethyl etherate / dichloromethane / 20 h / 20 °C / Inert atmosphere; Molecular sieve 6: methanol; sodium methylate / 3 h / 20 °C View Scheme

1: 98.2 percent / sodium methanolate / methanol / Ambient temperature 2: 94 percent / sodium hydroxide / methanol / 3 h / Ambient temperature View Scheme

sodium methylate in methanol Ambient temperature;

tetrabutylammomium bromide; sodium hydroxide in dichloromethane T=40°C; 4 h;

sodium acetate