A hydrovinylation

This reaction is very facile, and the use of 1 mole of acid provides a convenient method for the synthesis of vinyl complexes. The proposed mechanism (287) is shown in Fig. 6 which suggests an oxidative addition of HX followed by insertion into the Pt—H bond to form the intermediate vinyl compound. If excess acid is present, a second oxidative addition of HX occurs to give a hydrovinyl platinum(IV) intermediate. If a second insertion reaction occurs, the olefin is formed along with PtX2(PPh3)2. 

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