Protocatechuan aldehyde – ethylvanillin (3 4-dihydroxybenzaldehyde)
1g vanillin procedure Chemical products: Ethylvanillin Sulfuric acid (95-97%, pure) Ethyl acetate Ice Procedure: 5.5 g of concentrated sulfuric acid and a stirring bar were placed in a 150 ml beaker. Then 1 g of ethyl vanillin was added and stirred; The pieces turned a greenish color before dissolving in a clear yellow solution. The glass is covered with a watch glass, placed in an oil bath in the extractor hood, the temperature of the oil is raised to 70 °C and maintained for 4 hours.
Some smoke or fog is visible in the glass.
The reaction mixture that has now turned brown is removed from the oil bath and allowed to cool briefly before being poured over 11 g of crushed ice while stirring. It is a clear solution. The mixture is almost completely melted but still cold. It is then extracted once with 10 mL of ethyl acetate and then twice with 5 mL of ethyl acetate each. The color passes mainly to the organic layer (reddish). The organic layers are combined, dried over some sodium sulfate and then evaporated to a volume of about 2-3 ml which is allowed to evaporate at room temperature. Grayish crystals with blue and green reflections are obtained that are left to dry in the air for half a day. They weigh 0.77g (93%).
The solids redissolved in approximately 4.4 g of hot water, giving a brown solution. After cooling to room temperature, crystallization had to be started by scraping with a spatula. The crystal suspension was then placed in the refrigerator for several hours. Vacuum filtration over a Büchner funnel provides a slightly brownish crystalline product. After air drying it weighs 0.51 g (63%)
This is the link from which I made the synthesis of protocachualdeido - (3 4-dihydroxybenzaldehyde) from vanillin, the result was 0.88 g
1g vanillin procedure Chemical products: Ethylvanillin Sulfuric acid (95-97%, pure) Ethyl acetate Ice Procedure: 5.5 g of concentrated sulfuric acid and a stirring bar were placed in a 150 ml beaker. Then 1 g of ethyl vanillin was added and stirred; The pieces turned a greenish color before dissolving in a clear yellow solution. The glass is covered with a watch glass, placed in an oil bath in the extractor hood, the temperature of the oil is raised to 70 °C and maintained for 4 hours.
Some smoke or fog is visible in the glass.
The reaction mixture that has now turned brown is removed from the oil bath and allowed to cool briefly before being poured over 11 g of crushed ice while stirring. It is a clear solution. The mixture is almost completely melted but still cold. It is then extracted once with 10 mL of ethyl acetate and then twice with 5 mL of ethyl acetate each. The color passes mainly to the organic layer (reddish). The organic layers are combined, dried over some sodium sulfate and then evaporated to a volume of about 2-3 ml which is allowed to evaporate at room temperature. Grayish crystals with blue and green reflections are obtained that are left to dry in the air for half a day. They weigh 0.77g (93%).
The solids redissolved in approximately 4.4 g of hot water, giving a brown solution. After cooling to room temperature, crystallization had to be started by scraping with a spatula. The crystal suspension was then placed in the refrigerator for several hours. Vacuum filtration over a Büchner funnel provides a slightly brownish crystalline product. After air drying it weighs 0.51 g (63%)
This is the link from which I made the synthesis of protocachualdeido - (3 4-dihydroxybenzaldehyde) from vanillin, the result was 0.88 g
