Synthesis of Symmetrical and Unsymmetrical Diarylalkynes from Propiolic Acid Using Palladium-Catalyzed Decarboxylative Coupling
Citations Over TimeTop 10% of 2010 papers
Abstract
Symmetrical diarylalkynes were obtained from propiolic acid (or 2-butynedioic acid) and aryl halides in good yields. The optimized reaction conditions were 2.0 equiv of aryl halide, 1.0 equiv of propiolic acid, 5.0 mol % Pd(PPh(3))(2)Cl(2), 10.0 mol % 1,4-bis(diphenylphosphino)butane (dppb), 2.0 equiv of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), and dimethyl sulfoxide (DMSO) as the solvent. The coupling reaction of 2-butynedioic acid with aryl halides required 110 °C. The coupling reaction showed tolerance for functional groups such as ester, ketone, and aldehyde and exhibited chemoselectivity. In the coupling reaction of propiolic acid with aryl bromide, the diarylated product was the major one at 80 °C, even though 1 equiv of aryl halides was employed. However, among the monoarylated products that were formed predominantly at 25 and 50 °C in the coupling reaction with aryl iodide, more Sonogashira coupling product was obtained than the decarboxylative coupling product. Unsymmetrical diarylalkynes were also synthesized via this method, in which all reagents, including propiolic acid, aryl iodide, and aryl bromides were added at the beginning of the reaction.
Related Papers
- → Parallel recognition by virtue of differentiation between ketone and aldehyde(1998)13 cited
- Progress in synthesis and modification of ketone-aldehyde resin(2006)
- Discussion on oxidation of aldehyde and ketone(2001)
- The Synthesis of 2-Furyltriisopropoxytitanium and its Reactivity to Carbonyl Compounds(1996)
- A Study on the Synthesis of 2-Thiophenyltriisopropoxytitanium and its Reactivity to Carbonyl Compounds(1994)