7433-92-3

Upstream product

• 85-44-9 phthalic anhydride 
• 4122-56-9 methyl o-formylbenzoate 
• 601-70-7 3,3-dichlorophthalide 
• 938-24-9 indantrione 
• 6630-33-7 ortho-bromobenzaldehyde 
• 201230-82-2 carbon monoxide 
• 61592-98-1 1,2-bis(2-bromophenyl)-2-hydroxyethan-1-one 

Downstream Products

• 645-49-8 cis-stilben 
• 78229-60-4 4b,10b-Dihydro-13-syn,14-anti-diphenyl-4b,10b-ethano<2>benzopyrano<4,3-c><2>benzopyran-6,12-dion 

Relevant academic research and scientific papers

Palladium-Catalyzed Double Carbonylative Cyclization of Benzoins: Synthesis and Photoluminescence of Bis-Ester-Bridged Stilbenes

A palladium-catalyzed double carbonylative cyclization of benzoins has been developed, which realizes the synthesis of bis-ester-bridged stilbenes just in two steps from aldehydes. Thus, the obtained fully fused tetracyclic π-systems have a pyrano[3,2-b]pyran-2,6-dione (PPD) core on their center, showing two reversible reductions at low potentials. In addition, their photoluminescence properties are strikingly affected by the aromatic rings fused to the PPD core; bis-thieno-fused PPDs are found to be excellent fluorophores with quantum yields up to 0.98.

High-Intensity Laser-Jet Photochemistry: Formation of Benzocyclobutenedione from 1,2,3-Indantrione via Transient Targeting

The photochemistry of 1,2,3-indantrione (1) under high-intensity (laser-jet) conditions has been investigated.Irradiation of trione 1 in a benzene solution under laser-jet conditions produces a complex mixture in which benzocyclobutenedione (2) is observed to be the sole high-intensity product (ca. 11percent yield, six cycles, 3..5 W MLUV argon ion laser) as compared to conventional irradiation (dispersed laser beam, 20 min, 3.5 W MLUV argon ion laser).Under similar conditions, dione 2 was not observed to undergo photolysis in the laser-jet (mass balance ca. 90percent).Additionally, phthalic anhydride, (E)-1,1'-bis-isobenzofuranylidene-3,3'-dione ((E)-4), and 2-benzopyrano-benzopyran-6,12-dione (5) were identified also in both the laser-jet and conventional irradiations of both trione 1 and dione 2.In view of the previously reported product studies, it is proposed that the formation of dione 2 under laser-jet conditions occurs by a photochemical electrocyclization of the intermediary cyclohexadiene-1,2-bisketene (B).The decarbonylation of trione 1 to bisketene B and the electrocyclization of the transient bisketene B to dione 2 constitute an unprecedented sequential multiple-photon transformation of polyketones in solution, which has been uncovered through product studies by using the novel laser-jet technique.

ELECTROCHEMICAL REDUCTION OF PHTHALYL CHLORIDE. A NEW ROUTE FOR THE SYNTHESIS OF 3-SUBSTITUTED PHTHALIDES

The cathodic reduction, under various conditions, of phthalyl chloride enables efficient synthesis of (E)-biisobenzofuranyliden-3,3'-dion(4), (2)-benzopyrano - benzopyrano-6,12-dione (7), 3-chlorophtalide (8), phtalide (9), or (E)-3 phtalide (12); the structure of the latter compound was confirmed by X-ray crystallography.