Resorcinol → 1,3-Dimethoxybenzene

An aqueous phase consisting of resorcinol (2.20 g, 20 millimoles, Lancaster, 99%), tetrabutyl-ammonium bromide (1.30 g, 50% w/w solution in water, 2 millimoles, Sachem 821 East Woodward, Austin, Tex. 78704), sodium hydroxide (5.01 g, 50% w/w solution in water, 60 millimoles, Aldrich), and water (248.83 g) was treated with a mixture of dimethyl sulfate (12.63 g, 100 millimoles, Aldrich, 99+%) and 3-methylanisole (GC standard, 0.750 g, 6 millimoles, Aldrich, 99%). The excess molar concentration of sodium hydroxide was 0.5. The organic phase:aqueous phase weight ratio was 1:18. The two phase system was stirred mechanically (600 rpm, a calibrated photo-tachometer) at room temperature (25° C.). Aliquots were taken after 0, 1, 3, 5, 8, 12, and 18 minutes after the addition of the alkylating agent. When aliquots were taken the pH of the reaction mixture was checked to determine if the hydrolysis of dimethyl sulfate caused the system to become acidic. After 5 minutes of the reaction, the pH became acidic and the reaction mixture was treated with an additional amount of sodium hydroxide solution (3.50 g, 50 w/w solution in water). Aliquots were briefly centrifuged, the phases were separated and the organic phase was injected into the GC column. The yield of 1,3-dimethoxybenzene based on the limiting reactant (resorcinol) was 47% after 12 minutes of reaction.

1. concentrationThe excess molar concentration of sodium hydroxide
2. customat room temperature
3. custom(25° C.)
4. customafter 0, 1, 3, 5, 8, 12, and 18 minutes
5. additionafter the addition of the alkylating agent
6. customto determine if the hydrolysis of dimethyl sulfate
7. customAfter 5 minutes of the reaction
8. customthe phases were separated
9. customafter 12 minutes
10. customof reaction

ORD record

ord-737a39de49af4ceb8b6408aa50c4ed2e

Source dataset

uspto-grants-2005_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06846946B2