 It undergoes a rearrangement reaction with hydrohalic acids to which the appropriate salt can be added to form the organometallic pentamethylcyclopentadienyl rhodium dichloride and pentamethylcyclopentadienyl iridium dichloride dimers; consequently, it can be used as a starting material for synthesising some pentamethylcyclopentadienyl organometallic compounds including [Cp*Rh(CO)2].Attempting a similar reaction with potassium tetrachloroplatinate results in the formation of a pentamethylcyclopentadiene complex, [(η4-Cp*H)PtCl2], indicating that the rhodium and iridium metal centres are necessary for the step in which the aromatic anion is formed.One of the alkenes can be epoxidized using "m"CPBA, peroxybenzoic acid, or dimethyldioxirane (DMDO).