Advanced Topic 845 of 1102 Organic Chemistry
Cross-Coupling Reactions
Palladium-catalyzed reactions such as Suzuki and Heck forming carbon-carbon bonds.
In-depth explanation of Cross-Coupling Reactions
Cross-coupling reactions use a palladium catalyst to join two organic fragments by forming a new carbon-carbon bond. The catalytic cycle involves oxidative addition of an organic halide to palladium, transmetalation with an organometallic partner, and reductive elimination to release the product and regenerate the catalyst. Suzuki coupling uses boronic acids, the Heck reaction couples aryl halides with alkenes, and Sonogashira coupling uses terminal alkynes. The 2010 Nobel Prize in Chemistry was awarded for this work, and the reactions are vital in drug synthesis.
Going deeper: Cross-Coupling Reactions
Key ideas: Palladium-catalysed formation of C-C bonds: Suzuki (aryl halide plus organoboron, base), Heck (aryl halide plus alkene), Sonogashira (aryl halide plus terminal alkyne with Cu), Negishi and Stille. General cycle: oxidative addition of R-X to Pd(0), transmetallation, reductive elimination. Reactivity of halides is I > Br > OTf > Cl. Awarded the 2010 Nobel Prize.
Common mistakes and connections: Students forget that Pd shuttles between oxidation states 0 and plus 2, or leave out the base needed in Suzuki coupling. Another error is expecting alkyl halides with beta hydrogens to couple easily; they undergo beta-hydride elimination. Links to organometallics, biaryl synthesis in pharmaceuticals and green solvent concerns.
Visualization of Cross-Coupling Reactions
The palladium cycle of oxidative addition, transmetalation and reductive elimination joins two carbon fragments and regenerates the catalyst. The interactive lesson shows this as a live animation or chart.
Worked example and use case
A Suzuki coupling of an aryl bromide with a phenylboronic acid gives a biaryl compound.
Frequently asked questions about Cross-Coupling Reactions
What is Cross-Coupling Reactions?
Palladium-catalyzed reactions such as Suzuki and Heck forming carbon-carbon bonds.
Is Cross-Coupling Reactions a beginner, intermediate or advanced topic?
Cross-Coupling Reactions is a advanced topic in Organic Chemistry. It builds on beginner and intermediate topics, so review those first if needed.
What should I learn before Cross-Coupling Reactions?
Study these earlier topics in Organic Chemistry first: Michael Addition, Pericyclic Reactions, Woodward-Hoffmann Rules.
What comes after Cross-Coupling Reactions?
The next topics in Organic Chemistry are Olefin Metathesis and Asymmetric Synthesis.
Can I practise Cross-Coupling Reactions with quizzes?
Yes. The interactive lesson includes a self-check question on Cross-Coupling Reactions, and the Organic Chemistry quiz draws on every topic in this area.
Where Cross-Coupling Reactions fits in Organic Chemistry
Cross-Coupling Reactions is topic 117 of 148 in Organic Chemistry.