Syntheses of a Flobufen Metabolite and Dapoxetine Based on Enantioselective Allylation of Aromatic Aldehydes
2014
Abstract
The enantioselective allylation of an aromatic aldehyde to give a chiral homoallylic alcohol was employed as the key step in the syntheses of a flobufen metabolite and dapoxetine. In the former case, the homoallylic alcohol moiety (99%ee) was converted into a five-membered lactone ring with good preservation of the optical purity, and the target compound, a flobufen metabolite, was obtained in 95%ee.
In the latter case, the homoallylic alcohol moiety (97%ee) was transformed over several steps into a 3-aminopropanol moiety. During the course of the synthesis, the gradual loss of optical purity was observed, and the target compound, dapoxetine, was obtained in 85%ee.