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This article explores the synthesis of 1,2-diketones, which are important compounds in the pharmaceutical and chemical industries. Traditional methods have limitations, so researchers have been investigating new strategies. The article focuses on the use of palladium-catalyzed carbonylation reactions and the development of a recyclable heterogeneous palladium catalyst. The study provides detailed experimental procedures and optimization of reaction conditions. [Extracted from the article]

A novel, highly efficient heterogeneous palladium‐catalyzed carbonylative cyclization of aryl iodides and benzyl acetylenes has been developed under an atmospheric pressure of CO. The reaction proceeds smoothly in a bioderived solvent 2‐methyltetrahydrofuran (2‐MeTHF) at 50 °C using an MCM‐41‐anchored bidentate phosphine palladium complex [Pd(OAc)2‐MCM‐41‐P,P] as catalyst with DiPEA as base, delivering a wide variety of 3‐alkylidenefuran‐2‐ones in good to excellent yields. The Pd(OAc)2‐MCM‐41‐P,P complex can be easily recovered by a simple centrifugation and recycled more than ten times without any remarkable loss of catalytic activity. The present method not only avoids the use of toxic solvents such as benzene, toluene and THF, but also addresses the key problem of expensive palladium catalyst recovery and recycle, thus preventing palladium contamination in the final product. [ABSTRACT FROM AUTHOR]

A highly efficient heterogeneous palladium-catalyzed carbonylative cyclization of aryl iodides and 2-hydroxyacetophenones is developed. The reaction proceeds efficiently in DMSO at 120 °C under 3 bar of carbon monoxide by using 2 mol% of an MCM-41-immobilized bidentate phosphine palladium complex [MCM-41-2P-Pd(OAc)2 ] as the catalyst and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the base, providing a general, efficient and practical approach for the assembly of a wide variety of flavones in mostly good to high yields from readily available starting materials. This supported palladium catalyst can be easily recovered via centrifugation of the reaction mixture and recycled more than nine times without any significant loss of its catalytic efficiency. [ABSTRACT FROM AUTHOR]