A Green and Environmentally Friendly, An Improved Synthesis of Pimavanserin (5-HT2A Receptor)

Water mediated and environmentally friendly, step-wise an improved synthesis of pimavanserin have been developed from the key intermediate of 1-(4-fluorobenzyl)-3-(4-isobutoxybenzyl)-1-(1-methyl piperidin-4-yl) thiourea at different solvent conditions. These reactions have an easy workup; provide good to excellent yields, and uses water as the solvent which is considered to be relatively environmentally benign and no need of column chromatography for product isolation.