Cationic metal nitrosyl complexes. IV. Polymerization of olefins with dinitrosyl iron complexes

The polymerization of styrene was performed with new cationic iron complexes, (Fe(N‐O)2Sn)+PF6−(BF4−, CIO4−), where Sn represents solvent molecules such as CH2Cl2, THF, and MeCN. Kinetic experiments showed a first‐order dependence of (Rp)0 on the monomer and iron complex concentrations. The molecular weight determinations suggested that the termination process is fast and occurs by chain transfer to monomer. An extension of this polymerization to α‐methylstyrene, isobutene, tetrahydrofuran, and styrene‐methylmethacrylmate system emphasized the cationic nature of the reaction.