Hydrogenation of Cyclopropanes Having Other Unsaturated Groups

HYDROGENATION OF CYCLOPROPANES HAVING OTHER UNSATURATED GROUPS 

Cyclopropene is a highly strained system, but loss of a hydride ion gives the cyclopropenyl cation, which is formally an aromatic compound the tri(cyclopropyl) cyclopropenyl cation is very stable and can even exist in aqueous solution. Notwithstanding the very great strain in the parent hydrocarbon, the hydrogenation of methyl-substituted cyclopropenes has been reported.  

Consideration of the likely steric interference between the substituents and the surface led to the view that reaction involved arrival of the hydrocarbon at 

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