1,4-Cyclohexadiene

UsesReagent for selectively cleaving benzyl esters in the presence of benzyl ethers by catalytic H-transfer.

UsesForms benzene at elevated temperatures in the presence of a ruthenium(II)-triphenylphosphine catalyst.1

Uses1,4-Cyclohexadiene is used to study the formation of parent ion from heavy fragmentation on irradiation with a high-intensity laser pulse. It is also used as a very effective hydrogen donor for catalytic hydrogenation reaction. It forms benzene at elevated temperatures in the presence of a ruthenium(II)-triphenylphosphine catalyst.

General Description1,4-Cyclohexadiene is an effective hydrogen donor for catalytic hydrogenation reactions. It can rapidly replace benzyl groups of N-benzyloxycarbamates, benzyl esters, benzyl ethers and benzyl amines with hydrogen. It forms benzene at elevated temperatures in the presence of a ruthenium(II)-triphenylphosphine catalyst.

PreparationCyclohexa-1,4-diene is typically prepared by Birch reduction, which involves reducing benzene with metallic lithium or sodium in liquid ammonia. However, Cyclohexa-1,4-diene is unstable and readily oxidized to aromatic benzene. In the laboratory, this conversion is usually carried out using olefins (such as styrene) and transfer hydrogenation agents (such as charcoal-based palladium) as catalysts.