Stereoselective Copolymerization of Butadiene and Functionalized 1,3-Dienes.

[(Mesitylene)nickel(allyl)+][BArF4-] (Ni-1) catalyzes the 1,4-cis selective copolymerization of isoprene and 1,3-butadiene with 15 (RO)3Si-, R2N-, RSO2-, RSO2NH-, and (RO)2B-functionalized 1,3-dienes. Incorporation of the functionalized 1,3-diene occurs very efficiently with high comonomer conversions, as observed, for example, for copolymerizations of 1,3-butadiene with (EtO)3Si(CH2)3C(═CH2)CH═CH2 (1), PhS(O)2(CH2)3C(═CH2)-CH═CH2 (7), or (pinB)C(═CH2)C(CH3)═CH2 (15), while copolymerization rates vary from strongly to slightly decreased when compared to butadiene homopolymerizations.