Sustainable Process for Sparteine Sulfate Preparation

(−)-Sparteine sulfate is a stable salt of the quinolizidine chiral diamine alkaloid (−)-sparteine. This compound, in addition to presenting various biological activities, has successfully been used as a ligand and organocatalyst in enantioselective lithiation reactions in asymmetric synthesis. (−)-Sparteine free base deteriorates gradually, even in refrigeration, but its stable salt, (−)-sparteine sulfate, offers advantages in handling and storage. To the best of our knowledge, no process exists in the literature for obtaining (−)-sparteine sulfate from the species of the plant genus Lupinus. In this work, we present an efficient and sustainable process to obtain (−)-sparteine sulfate and free base (−)-sparteine from leaves and stems of Lupinus montanus.