反应详情

The compounds useful as solubilization inhibition agents according to this invention can be easily prepared, for example, by esterifying 3,5-dioxocyclohexane carboxylic acid with the alkanol according to known esterification procedures and converting the resulting 3,5-dioxocyclohexane carboxylic acid ester to the corresponding 4-diazo-3,5-dioxocyclohexane carboxylic acid ester by reacting the ester with any suitable sulfonylazide, such as p-toluenesulfonyl azide (TSA) or naphthylenesulfonyl azide (NSA), in the presence of a catalyst such as dry triethylamine and any suitable solvent such as ethanol, benzene or acetonitrile any the like. Generally after reacting for a period of about 3 to about 15 hours the reaction mixture is filtered to remove the precipitated sulfonamide and the filtrate is evaporated to dryness. The product may then be partially purified by partitioning between methylene chloride and dilute alkali hydroxide. The residues may be purified either by recrystallization, if the product is a solid, or by chromatography, such as flash chromatography on silica gel if the product is an oil.

1. waitGenerally after reacting for a period of about 3 to about 15 hours
2. filtrationthe reaction mixture is filtered
3. customto remove the precipitated sulfonamide
4. customthe filtrate is evaporated to dryness
5. customThe product may then be partially purified
6. customby partitioning between methylene chloride and dilute alkali hydroxide
7. customThe residues may be purified either by recrystallization, if the product