It's impossible. If the pair position is already occupied by the methoxy group, it cannot be shifted to the position along the benzene ring in 2 or 5.
Synthesis of 2,5-dimethoxybenzaldehyde from anise oil (small scale)
- Thread starter WillD
- Start date
Hi frend in step 4, At this stage you did not convert the salt with dilute acid, your writing is incomplete and the yield you reported is high, is this yield real???
200g of hydroquinone monomethyl ether were dissolved in a solution of 190 g of sodium hydroxide in 550 ml of water and the resulting solution was heated to 50°C on a water bath. To the solution maintained at 50-60°C, there were added dropwise 420 g of chloroform and a solution of 560 g of sodium hydroxide in 500 ml of water from two separate dropping funnels and, thereafter, the reaction mixture was heated for 1 hour at a temperature of 50-60°C and atmospheric pressure. After cooling, the precipitated sodium salt of 2-hydroxy-5-methoxybenzaldehyde was recovered by filtration and washed with 100 ml of ethanol.The sodium salt thus obtained was dissolved in 800 ml of water, slightly acidified with dilute sulphuric acid (1200 mL of 3N dilute sulphuric acid were added at room temperature and atmospheric pressure) and then extracted with 200 ml of toluene. The extract was dried with calcium chloride, distilled to eliminate toluene and then distilled under reduced pressure to obtain 132 g of 2-hydroxy-5 methoxybenzaldehyde having a boiling point of 110°C/5mmHg.
200g of hydroquinone monomethyl ether were dissolved in a solution of 190 g of sodium hydroxide in 550 ml of water and the resulting solution was heated to 50°C on a water bath. To the solution maintained at 50-60°C, there were added dropwise 420 g of chloroform and a solution of 560 g of sodium hydroxide in 500 ml of water from two separate dropping funnels and, thereafter, the reaction mixture was heated for 1 hour at a temperature of 50-60°C and atmospheric pressure. After cooling, the precipitated sodium salt of 2-hydroxy-5-methoxybenzaldehyde was recovered by filtration and washed with 100 ml of ethanol.The sodium salt thus obtained was dissolved in 800 ml of water, slightly acidified with dilute sulphuric acid (1200 mL of 3N dilute sulphuric acid were added at room temperature and atmospheric pressure) and then extracted with 200 ml of toluene. The extract was dried with calcium chloride, distilled to eliminate toluene and then distilled under reduced pressure to obtain 132 g of 2-hydroxy-5 methoxybenzaldehyde having a boiling point of 110°C/5mmHg.
So this is another write-up using hydroquinine as starting material? Could you please provide osurce for this? Is it a synth that you performed yourself or is it just a quote?
It's taken from here https://www.thevespiary.org/rhodium/Rhodium/chemistry/25-dimethoxybenzaldehyde.html