An Efficient and Practical Enantiospecific Synthesis of Methyl Chromanone‐ and Chroman‐2‐carboxylates.

Abstract Chromanone-2-carboxylates and chroman-2-carboxylates are useful building blocks for the synthesis of a variety of bioactive compounds, such as repinotan, fidarestat, and nebivolol. An efficient and practical enantiospecific synthesis of chromanone-2-carboxylates and chroman-2-carboxylates has been accomplished using intramolecular Mitsunobu etherification of methyl ( S )-2-hydroxy-4-oxo-4-(2′-hydroxy)phenylbutanoates derived from l -malic acid.