Citric Acid → Sufentanil Citrate

Participants

Reaction Steps

Sufentanil HCl obtained in Example 8 was suspended in hot water and adjusted to pH 10-11 with 10% aqueous potassium hydroxide and extracted with ether. The organic layer washed with water, dried and evaporated to give the free base with an LC purity profile of 99.62%. An equivalent of sufentanil free base with anhydrous citric acid was warmed in 100% ethanol. After removal of ethanol the fluffy white powder was dried in the vacuum oven at 56° C. for 48 hrs. Sufentanil citrate thus obtained passed all USP tests.

Provenance & Evidence