Reactions Of Substituted Quinones Site

) on the quinone accelerate the reaction by lowering the LUMO energy.

If the quinone has a good leaving group (like a halogen in p-chloranil ), a nucleophile can displace it directly. This is a common route for synthesizing complex dyes and bioactive molecules. 5. Photochemical Reactions reactions of substituted quinones

The "ortho/para" rule applies here; substituents on the diene and the quinone will orient themselves to maximize electronic stabilization in the transition state. 3. Redox Chemistry (Reduction) Quinones are easily reduced to hydroquinones. ) on the quinone accelerate the reaction by

Under UV light, substituted quinones can undergo [2+2] cycloadditions or abstract hydrogen atoms from solvents. This is frequently used in polymer chemistry and the study of DNA damage. Redox Chemistry (Reduction) Quinones are easily reduced to

Large groups can hinder the approach of the diene, often dictating which face of the quinone is attacked.

This reversible redox cycle is how Coenzyme Q (Ubiquinone) transports electrons in the mitochondrial respiratory chain. 4. Nucleophilic Substitution ( SNArcap S sub cap N cap A r

Electron-withdrawing groups make the quinone a stronger oxidant (easier to reduce). Electron-donating groups (like −OMenegative cap O cap M e −CH3negative cap C cap H sub 3 ) make the quinone more stable and harder to reduce.