Transpositive Tandem Annulation of Phthalides with Allene Carboxylates: Regioselective Synthesis of Arylnaphthalene Lignans was written by Mal, Dipakranjan;Jana, Supriti. And the article was included in Journal of Organic Chemistry in 2016.Safety of 5-Methoxyisobenzofuran-1(3H)-one This article mentions the following:
Allene carboxylates, scarcely used as Michael acceptors, serve as acceptors in the annulation with phthalides in the presence of LDA and provide a one-pot synthesis of naphtho[c]furanones in very good yields. This tandem annulation is proposed to proceed via transposition of the hydroxy group resulting from the initial annulation. In the experiment, the researchers used many compounds, for example, 5-Methoxyisobenzofuran-1(3H)-one (cas: 4741-62-2Safety of 5-Methoxyisobenzofuran-1(3H)-one).
5-Methoxyisobenzofuran-1(3H)-one (cas: 4741-62-2) belongs to benzofurans derivatives. Benzofurans are only weakly aromatic in nature and they are cleaved by many oxidative and reductive conditions. Benzofurans are stable towards alkali and readily polymerize on treatment with sulfuric acid, due to which they are useful for the preparation of low cost chemically relatively inert resins.Safety of 5-Methoxyisobenzofuran-1(3H)-one
Referemce:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem