Heteroatoms enhance polymerization and copolymerization of functional olefins.

The efficient and selective ortho-alkylation of N,N-dimethyl anilines via C–H addition to alkenes was achieved for the first time using a cationic half-sandwich yttrium catalyst. This protocol constitutes a straightforward and atom-economical route for the synthesis of a new family of tertiary aniline derivatives with branched alkyl substituents, which are otherwise difficult to obtain. DFT calculation studies suggest that the interaction between the yttrium atom and the NMe₂ group plays an important role and the intramolecular C–H activation through a σ-bond metathesis pathway is the rate-determining step, which is consistent with the experimental KIE observations.

DFT calculations have been carried out on the Sc-catalyzed regioselective hydroaminoalkylation of olefins with amines. It has been revealed that the true active species is an amine-coordinated η²-azametallacyclic complex, and electronic factors play a crucial role in achieving regioselectivity. The charge dispersion and charge alternation account well for the stability of the olefin insertion transition states and products. The charge distribution of 15 olefin substrates used previously in the experimental studies correlates well with the observed regioselectivity and could thus provide a potential model for regioselectivity prediction. The reactivity of different types of C–H bonds was also explored by modeling the reaction of (CH₂C₆H₄NMe₂-o)₂Sc⁺ with ⁱPrN(Me)(Et). The suggested reactivity trend for the Sc-catalyzed hydroaminoalkylation follows the order of primary C–H bond > secondary C–H bond > tertiary C–H bond.