Reactions of Olefin Complexes with Electrophiles

Strong n back-bonding increases negative charge on olefin carbon atoms and increases their nucleophilicity this facilitates attack by electrophiles. The coordination of olefins by Pt(0) so greatly increases their nucleophilicity that even such strong n acids 

Protonation of the olefin probably takes place during formation of [RhCl(CO)L2] [L = PPh3 ,(C6F5), x= 1-3] from [RhClL3] in the presence of C2F4 and water. 

Owing to protonation of ethylene, [Rh2Cl2(C2H4)]4 catalyzes ethylene dimerization [equation (6.128)]. 

Some olefin coordination compounds may react with hydrogen acceptors to give allyl complexes. The ligand itself may serve as the acceptor  

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