catalyst precursors. The copolymers are highly branched, the acrylate comonomer being incorporated predominantly at the ends of branches as −CH2CH2C(O)OMe groups. The effects of reaction conditions and catalyst structure on the copolymerization reaction are rationalized. Low-temperature NMR studies show that migratory insertion in the η2-methyl acrylate (MA) complex [(N∧N)PdMeH2CCHC(O)OMe}]+ (5) occurs to
描述了
钯催化的
乙烯和α-烯烃与
丙烯酸甲酯插入共聚反应以得到高摩尔质量聚合物的机理方面。配合物 [(N∧N)Pd(
CH2)3C(O)OMe]BAr'4 (2) 或 [(N∧N)Pd(
CH3)(L)]BAr'4 (1: L = OEt2; 3: L ⋮ NCMe; 4: L ⋮ NCAr') (N∧N ≡ ArNC(R)−C(R)NAr, 例如 Ar ⋮ 2,6-
C6H3(i-Pr)2, R ⋮ H (a), Me (b); Ar' ⋮ 3,5- (
CF3)2) 与庞大的取代α-二
亚胺配体被用作催化剂前体。共聚物是高度支化的,
丙烯酸酯共聚单体主要作为- C(O)OMe 基团引入到支链末端。合理化了反应条件和催化剂结构对共聚反应的影响。低温 NMR 研究表明,在 η2-
丙烯酸甲酯 (MA) 复合物 [(N∧N)PdMeH2CCHC(O)OMe}]+ (5) 中发生迁移插入,最初产生