Sulfuric Acid → HCID 18434036, compound

Participants

Reaction Conditions

Reaction Steps

The solution of methyl 3-hydroxybenzoylacetate (about 4.0 kg) and toluene (total weight of solution 5.6 kg) from the step above was charged to a reaction vessel along with 3-methoxyphenol (2.55 kg). The mixture was stirred vigorously at 0° C. while 27 M sulfuric acid (5.55 L) was added over 5 minutes. The resulting dark solution was warmed to 25° C. When the reaction began to thicken (40 minutes), methanol (21.8 L) was added. The addition was exothermic. Continued stirring (15 minutes) yielded a smooth, brown slurry which was cooled to 5° C. over 25 minutes, stirred for one hour, then filtered. The filter cake was washed with methanol (5.50 L) and dried under vacuum at 45-50° C. to give 3.70 kg (13.8 mol, 70% yield for two steps) of 4-[3′-(hydroxy)phenyl]-7-methoxycoumarin (a compound of Formula (b)).

Provenance & Evidence