3-oxo-1 3-dihydroisobenzofuran-1-ylphosphonic acid CAS 61260-15-9

The Key Intermediates in Chemical Synthesis

This molecule is highly versatile in the eyes of organic chemicalists. The core value of 3-oxo-1 3-dihydroisobenzofuran-1-ylphosphonic acid lies in its clever integration of a reactive site with a modifiable and cleavable “handle” on the same molecular skeleton.

The most direct application of 3-oxo-1 3-dihydroisobenzofuran-1-ylphosphonic acid as a key intermediate for constructing complex molecules is as a key intermediate for synthesizing a series of more complex compounds.

The lactone ring of the benzoic acid can be opened by specific reagents in order to produce ortho substituted derivatives. These are structural units that are used for a variety of fine chemicals, liquid-crystal materials or active pharmaceuticals. The phosphonate can be used as a “protecting” or “directing” group to ensure the reaction takes place at the desired position during a complex multi-step synthesizing process. This will improve the selectivity and yield.

This is the classic and most important use of the phosphonate moiety. It can be used to participate in the Wittig Horner reactions and build carbon-carbon double bonds. Under alkaline conditions the adjacent hydrogen atoms in the phosphonate moiety of this molecule can also be removed to form a negatively-charged carbocation. This is similar to the famous Wittig Reaction. This carbon negative ion reacts efficiently with the carbonyl groups in aldehydes and ketones to form a new double carbon bond (C=C).

This is the Horner Wadsworth Emmons Reaction. This phosphonate-based reaction has many advantages over traditional Wittig reactions: it is milder, produces higher yields and faster, with lower temperatures. The phosphate esters produced are also soluble in water, making them easy to purify and separate.

Chemists can therefore use this molecule as a “molecular engineer” to precisely “install” a rigid benzofuranone structure fragment onto another molecular skeleton. This allows them to efficiently construct target molecules with specific double bond arrangements.

This tool is essential for the total synthesis and construction of functional materials molecules.

2. The “advantageous frame” in medicinal chemistry, and pesticide design

In the development of drugs and pesticides, combining heterocycles that have specific biological activity with phosphonate group is an effective strategy. 3-oxo-1 3-dihydroisobenzofuran-1-ylphosphonic acid provides such an advantageous framework.

Potential Therapeutic Activity:

Phthalimide derivatives and their biological activities have been proven in the past to include anti-inflammatory, convulsant and anti-tumor activity. They can interfere with specific enzymes’ normal function by embedding the compounds into their active pocket. This molecule, after adding the phosphonate, can mimic the natural phosphorylation or transition state of organisms. It will then more effectively bind to the active center and become a potential inhibitor. This opens up a wide range of possibilities for the development and production of drugs to treat cancer, metabolic disorders, and viral infections.


Pre-drug strategy: the phosphonate group is able to penetrate cell membranes and, once inside, can be hydrolyzed into phosphonic acids with a stronger biological activity. Therefore, 3-oxo-1 3-dihydroisobenzofuran-1-ylphosphonic acid itself can be considered as a prodrug, which optimizes the pharmacokinetic properties of the active ingredient and improves its bioavailability.



New pesticides are being developed:

The life cycle of pests, pathogens and weeds in agriculture is also dependent on specific enzyme systems. This molecule’s heterocyclic structure can act as a “warhead”, interfering with enzyme systems. The phosphonate moiety could mimic key phosphorylation intermediaries in plant or microbiological metabolism.

Therefore, using 3-oxo-13-dihydroisobenzofuran-1-ylphosphonic acid as the parent nucleus for structural optimization is expected to develop new herbicides, insecticides, or fungicides. By modifying the structure of this compound, compounds can be created that inhibit enzyme systems specific to plants or fungi, and achieve efficient and selective control.

3. Innovative components in materials science

Materials science has been able to benefit from the combination of polarizable groups and rigid aromatic rings in molecules.

The building block of metal-organic framework materials is the phosphonate group. These groups are excellent organic connectors, capable of forming strong and stable coordination binds with different metal ions. Metal organic framework materials can be built by using this molecule to bind metal salts.

This material is a great candidate for gas storage, separation, chemical sensors, multiphase catalysis and proton conductivity. The rigid core of benzofuranone helps form a stable structure while the phosphonate provides a strong bond with the metal nodes.

Modified monomers and additives for polymer materials: 3-oxo-1 3-dihydroisobenzofuran-1-ylphosphonic acid can be used as a functional monomer to participate in polymerization reactions through its double bond or ring opening functional group, introducing phosphonate groups into the polymer chain. This can improve the performance and durability of polymers such as:

Flame retardancy Phosphorus can be an effective flame retardant. By embedding such structural units in polymers, you can achieve flame retardant properties, promote carbonization and isolate oxygen during combustion.


Surface modification: Because phosphonate groups are attracted to metal oxide surfaces, polymers and small molecules with this structure make excellent surface treatment agents. They can also be used in adhesives or anti-corrosion coats that improve adhesion between materials.

Optical properties: The rigid conjugated structure of 3-oxo-1 3-dihydroisobenzofuran-1-ylphosphonic acid may endow the polymer with specific fluorescence or photoresponsive properties, which can be used to develop novel optical materials.