Method for preparation of salts of hydroxy-substituted aromatic compounds

A method for preparing an alkali metal salt of a hydroxy-substituted aromatic compound of formula IV, said method comprising steps (a)-(d):

• (a) contacting in an aqueous medium the hydroxy-substituted aromatic compound of formula IV with a base comprising an alkali metal cation to provide a mixture comprising water and an alkali metal salt of said hydroxy-substituted aromatic compound of formula IV;
• (b) contacting the mixture formed in step (a) with a substantially water-immiscible solvent at a temperature greater than the boiling point of water at the prevailing pressure to provide a slurry comprising the alkali metal salt of the hydroxy-substituted aromatic compound of formula IV and the water immiscible solvent, and a vapor stream comprising the substantially water-immiscible solvent and water;
• (c) introducing the vapor stream into a vapor handling system comprising a partial reflux condenser;
• and
• (d) separating the vapor stream to provide a water-rich component and a water immiscible solvent-rich component.

A method for preparing an alkali metal salt of a hydroxy-substituted aromatic compound of formula V, said method comprising steps (a)-(d):

• (a) contacting in an aqueous medium the hydroxy-substituted aromatic compound of formula V with a base comprising an alkali metal cation to provide a mixture comprising water and an alkali metal salt of said hydroxy-substituted aromatic compound of formula V;
• (b) contacting the mixture formed in step (a) with a substantially water-immiscible solvent at a temperature greater than the boiling point of water at the prevailing pressure to provide a slurry comprising the alkali metal salt of the hydroxy-substituted aromatic compound of formula V and the water immiscible solvent, and a vapor stream comprising the substantially water-immiscible solvent and water;
• (c) introducing the vapor stream into a vapor handling system comprising a partial reflux condenser;
• and
• (d) separating the vapor stream to provide a water-rich component and a water immiscible solvent-rich component.