Hydrogen Bromide → HCID 23287941, compound

Participants

Reaction Steps

1-(10,11-Dihydroxyundecanyl)-3,7-dimethylxanthine (3.6 g, 10 mmol) was stirred with hydrogen bromide (6.2 ml, 8.4 g of a 30% solution in acetic acid, 31.1 mmol) for 90 minutes. The mixture was then added to a flask containing 100 ml aqueous sodium bicarbonate solution and 75 ml dichloromethane. After 10 minutes of vigorous stirring, the layers were separated and the aqueous portion washed with dichloromethane (3×75 ml). The organic portions were combined, dried over magnesium sulfate, and evaporated to give 1-(10-acetoxy-11-bromoundecanyl)-3,7-dimethylxanthine (3.6 g). Without further purification, the bromoacetate was taken up in methanol (25 ml) and treated with a solution of sodium methoxide (prepared from 0.28 g, 12.2 mmol sodium, and 25 ml methanol). After 30 minutes most of the solvent was removed under reduced pressure and the residue was extracted with dichloromethane (3×75 ml). The organic portions were combined, dried over magnesium sulfate and concentrated under reduced pressure to give an off-white solid. Subsequent purification by column chromatography over silica gel using a dichloromethane/(3%) methanol eluant produced 2.0 g of 1-(10,11-oxidoundecanyl)-3,7-dimethylxanthine (57.5% yield).

Provenance & Evidence