“…These catalysts were very active in diene polymerizations under ambient temperature, providing binary cis-1,4/3,4, trans-1,4/3,4 polyisoprene, cis-1,4/1,2 (major) polybutadiene, as well as polymyrcene in some cases. [12][13][14][15] Over the past decades, there are significant progresses in stereoselective polymerization of butadiene promoted by iron, [16][17][18][19][20][21][22] cobalt, 23 chromium 24,25 and molydenium catalyts [26][27][28] with phosphine, phosphate or phosphite as an additive or ligand. Preceding this work, [16][17][18][19][20][21][22] we have reported phosphate and phosphite are efficient additives for iron catalyzed 1,2 stereopolymerization of butadiene.…”