Optimization of Palladium-Catalyzed One-Pot Synthesis of Functionalized Furans for High-Yield Production: A Study of Catalytic and Reaction Parameters

This study investigates the palladium-catalyzed one-pot synthesis of functionalized furans from 1,3-Dicarbonyl compounds and alkenyl bromides, focusing on various catalysts and reaction parameters. Different catalysts, including PdCl₂(CH₃CN)₂, Pd(OAc)₂, and Pd(acac)₂ as well as solvents, bases, and oxidants, were systematically evaluated. PdCl₂(CH₃CN)₂ emerged as the most effective catalyst, achieving a remarkable yield of 94%. Optimal reaction conditions were identified as PdCl₂(CH₃CN)₂ in dioxane at 80 °C with K₂CO₃ as the base and CuCl₂ as the oxidant. This study also explored various 1,3-diketones including Cyclohexane-1,3-dione, 5,5-Dimethylcyclohexane-1,3-dione, 2H-Pyran-3,5(4H,6H)-dione, Cyclopentane-1,3-dione, Pentane-2,4-dione, Ethyl 3-oxobutanoate, 1,3-Diphenylpropane-1,3-dione, 1,3-Dip-tolylpropane-1,3-dione, 1,3-Bis(4-chlorophenyl)propane-1,3-dione, and 1,3-Bis(4-bromo- phenyl)propane-1,3-dione, alongside different alkenyl bromides such as allyl bromide, (E)-1-Bromo-3,4-dimethylpent-2-ene, 1-Bromo-3-methylbut-2-ene, 3-Bromocyclohex-1-ene, and (E)-1-Bromohex-2-ene. These variations demonstrated the method’s versatility and the significant impact of substituents on reactivity and reaction yield. These findings highlight the importance of optimizing reaction conditions to maximize efficiency and provide insights into improving catalytic processes for enhanced product yields.