Dimethyl (3-oxo-1,3-dihydroisobenzofuran-1-yl)phosphonate

Dimethyl (3-oxo-1,3-dihydroisobenzofuran-1-yl)phosphonate is a phthalide-based olefination reagent. Its phosphonate-bearing carbon participates in carbon–carbon double-bond formation, while the lactone transfers a preassembled benzofused carbonyl framework. Reaction with an aromatic aldehyde produces a benzylidene phthalide that can enter further ring-conversion chemistry.

The selected structure is the dimethyl phosphonate ester, rather than an unesterified phosphonic acid. This distinction defines the reagent used in Horner-type coupling. The phosphonate enables formation of the exocyclic alkene, whereas the retained lactone supports later transformation into nitrogen-containing fused rings. This connects aromatic-fragment assembly to subsequent construction of the phthalazinone scaffold.

Typical Applications

• Olaparib benzylidene-lactone synthesis: Used with a fluorinated formylbenzonitrile to construct the exocyclic alkene connecting the phthalide-derived and fluorinated aromatic fragments.
• Substituted phthalide frameworks: Used in olefination with alternative aldehydes to produce benzylidene phthalides, providing unsaturated lactone scaffolds for subsequent reduction or heterocycle-forming reactions.

Specifications

Specifications describe the standard grade. Tolerance, test method and documentation package are confirmed per order.