Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List Benzoic acid, 3,4-dihydroxy-2-Methyl-, Methyl ester
740799-82-0

Benzoic acid, 3,4-dihydroxy-2-Methyl-, Methyl ester synthesis

4synthesis methods
-

Yield:-

Reaction Conditions:

Stage #1: 2-methyl-3,4-dimethoxybenzoic acidwith boron tribromide in dichloromethane at 20; for 2 h;Cooling with ice;
Stage #2: methanol in dichloromethane at 20; for 48 h;Cooling with ice;

Steps:

103.1 Step (1): compound ii-38a → compound ii-38b

Boron tribromide (12.05 mL, 127 mmol) was added to a solution of compound ii-38a (10.0 g, 51.0 mmol, synthesized with reference to a method described in WO 2009/55077 A1) in dichloromathane (60 mL) while cooled with ice. The resultant solution was stirred at room temperature for 2 hours. The reaction liquid was added to methanol (100 mL) while cooled with ice. The resultant was stirred at room temperature for 2 days. The reaction liquid was diluted with dichloromethane/methanol, washed with a saturated salt solution, and dried over magnesium sulfate. Magnesium sulfate was filtrated off, and then the liquid was concentrated under reduced pressure. Thereto was added diisopropyl ether to precipitate a solid. The solid was collected by filtration, so as to yield compound ii-38b (2.86 g, 31%. The solid precipitated while the filtrate was separated to two phases was filtrated, and washed with water to yield compound ii-38b (3.30 g, 36%).1H-NMR (DMSO-d6) δ: 10.05 (1H, br s), 8.46 (1H, br s), 7.23 (1H, d, J = 8.46 Hz), 6.67 (1H, d, J = 8.46 Hz), 3.73 (3H, s), 2.34 (3H, s).

References:

EP2557082,2013,A1 Location in patent:Paragraph 0407; 0408

Benzoic acid, 3,4-dihydroxy-2-Methyl-, Methyl ester Related Search: