Patent ID: 7057047

Claim:
A method of making (+)-2-(7-chloro-1,8-naphthyridin-2-yl)-3-(5-methyl-2-oxohexyl)-1-isoindolinone, the method comprising the steps of: a.) reacting 2-diaminopyridine with malic acid and sulfuric acid to form 2-amino-7-hydroxy-1,8-naphthyridine sulfuric acid salt; b) reacting 2,6-amino-7-hydroxy-1,8-naphthyridine sulfuric acid salt with a phthalyl reactant in solvent to form phthalimidyl naphthyridine 2 c) reacting phthalimidyl naphthyridine 2 with a chlorinating agent to form chloride 3 d) reacting chloride 3 with a reducing agent to form hydroxyindolinone 4 e) reacting hydroxyindolinone 4 with a 5-methyl-2-oxo-hexyltriphenylphosphonium halide to form racemic 2-(7chloro-1,8-naphthyridin-2-yl)-3-(5methyl-2-oxohexyl)-1-isindolinone; and f) resolving racemic 2-(7-chloro-1,8-naphthyridin-2-yl)-3-(5-methyl-2-oxohexyl)-1-isoindolinone to provide (+)-2-(7-chloro-1,8-naphthyridin-2-yl)-3-(5methyl-2-oxohexyl)-1-isoindolinone.