22303-62-4

Basic information

• Product Name: 2(3H)-Benzofuranone, 3-hydroxy-
• Synonyms: 2(3H)-Benzofuranone, 3-hydroxy-
• CAS NO: 22303-62-4
• Molecular Formula: C₈H₆O₃
• Molecular Weight: 0
• Mol File: 22303-62-4.mol
• Article Data: 1

Chemical Properties

• Appearance: /
• CAS DataBase Reference: 2(3H)-Benzofuranone, 3-hydroxy-(CAS DataBase Reference)
• NIST Chemistry Reference: 2(3H)-Benzofuranone, 3-hydroxy-(22303-62-4)
• EPA Substance Registry System: 2(3H)-Benzofuranone, 3-hydroxy-(22303-62-4)

Safety Data

• Hazardous Substances Data: 22303-62-4(Hazardous Substances Data)

Upstream product

• 118-93-4 o-hydroxyacetophenone 
• 34073-50-2 3-diazo-2,3-dihydro-2-benzofuranone 

Downstream Products

• 17392-20-0 2-(2-hydroxyphenyl)quinoxaline 
• 1678-71-3 2-hydroxymandelic acid 
• 17375-97-2 2-Hydroxybenzoylmethyl-2-hydroxyphenylglyoxylat 
• 17392-16-4 (2-hydroxyphenyl)oxoacetic acid 

Relevant articles and documents

Photoreactions of 3-Diazo-3H-benzofuran-2-one; Dimerization and Hydrolysis of Its Primary Photoproduct, A Quinonoid Cumulenone: A Study by Time-Resolved Optical and Infrared Spectroscopy

Light-induced deazotization of 3-diazo-3H-benzofuran-2-one (1) in solution is accompanied by facile (CO)-O bond cleavage yielding 6-(oxoethenylidene)-2,4-cyclohexadien-1-one (3), which appears with a rise time of 28 ps. The expected Wolff-rearrangement product, 7-oxabicyclo[4.2.0]octa-1,3,5-trien-8-ylidenemethanone (4), is not formed. The efficient light-induced formation of the quinonoid cumulenone 3 opens the way to determine the reactivity of a cumulenone in solution. The reaction kinetics of 3 were monitored by nanosecond flash photolysis with optical (λ max ≈ 460 nm) as well as Raman (1526 cm-1) and IR detection (2050 cm-1). Remarkably, the reactivity of 3 is that expected from its valence isomer, the cyclic carbene 3H-benzofuran-2-one-3-ylidene, 2. In aqueous solution, acid-catalyzed addition of water forms the lactone 3-hydroxy-3H-benzofuran-2-one (5). The reaction is initiated by protonation of the cumulenone on its β-carbon atom. In hexane, cumulenone 3 dimerizes to isoxindigo ((E)-[3,3′ ]bibenzofuranylidene-2,2′-dione, 7), coumestan (6H-benzofuro[3,2-c][1]benzopyran-6-one, 8), and a small amount of dibenzonaphthyrone ([1]benzopyrano[4,3-][1]benzopyran-5,11-dione, 9) at a nearly diffusion-controlled rate. Ab initio calculations (G3) are consistent with the observed data. Carbene 2 is predicted to have a singlet ground state, which undergoes very facile, strongly exothermic (irreversible) ring opening to the cumulenone 3. The calculated barrier to formation of 4 (Wolff-rearrangement) is prohibitive. DFT calculations indicate that protonation of 3 on the β-carbon is accompanied by cyclization to the protonated carbene 2H +, and that dimerization of 3 to 7 and 9 takes place in a single step with negligible activation energy.