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The synthesis of self-healing polymers by catalyst-controlled copolymerization of commodity olefins is of fundamental interest and practical importance but remains highly challenging. We report here the synthesis of a new family of self-healing elastomers through terpolymerization of ethylene (E), styrene (St), and dimethylaminophenyl-substituted propylene (AMP) using a sterically demanding half-sandwich scandium catalyst. The terpolymers, comprising AMP–alt–(E–E) sequences and St–Stand E–Eblocks, exhibited excellent elasticity and rapid self-healing properties. Notably, employing 4-tert-butylstyrene instead of unsubstituted styrene in the terpolymerization yielded the corresponding terpolymers with further enhanced mechanical strength and self-healing capabilities. X-ray diffraction analyses and scanning transmission electron microscopy (STEM) images of an E–St–AMPterpolymer revealed a nanophase-separated structure comprising crystalline E–Eand glassy amorphous St–Stnanodomains dispersed in a rubbery AMP–E–Ematrix, providing insights into its remarkable mechanical and self-healing properties. This work represents a significant advancement in the synthesis of olefin-based self-healing polymers with potential applications in various fields.

The conversion of carbon monoxide (CO) to hydrocarbons and oxygenates on industrial solid catalysts (the Fischer–Tropsch reaction) largely relies on the cooperation of heteromultimetallic active sites composed of main group (such as alkali) and transition metals, but the mechanistic details have not been fully understood at the molecular level. Here we report the cooperative trimerization of CO by molecular lithium and samarium boryl complexes. We have found that, in the coexistence of a samarium boryl complex and a lithium boryl complex, the trimerization of CO selectively occurred to give a diborylallenetriolate skeleton “BC(O)C(O)C(O)B”, in sharp contrast with the reaction of CO with either the lithium or the samarium boryl compound alone. The 13C-labeled experiments and computational studies have revealed that the CO trimerization reaction took place exclusively by coupling of a samarium boryl oxycarbene species, which was generated by insertion of one molecule of CO into the samarium–boryl bond, with a lithium ketenolate species formed by insertion of two molecules of CO into the lithium–boryl bond. These results offer unprecedented insight into CO oligomerization promoted by heteromultimetallic components and may help better understand the industrial F–T process and guide designing new catalysts.

Stereodivergent asymmetric catalysis is an important technology that can allow efficient access to various stereoisomers of a given product with multiple stereocenters from the same set of starting materials, but its application to the synthesis of a highly strained cyclopropane compound has remained unexplored to date. We report here the first diastereodivergent enantioselective synthesis of bicyclic aminocyclopropanes by lanthanum-catalyzed asymmetric carboamination/annulation of cyclopropenes with aminoalkenes. This protocol features 100% atom efficiency, good yield (up to 90%), and high chemo- (up to >20:1) and stereoselectivity (up to >20:1 dr and 99% ee), constituting a unique route for the efficient synthesis of two different diastereoisomers of a given chiral bicyclic aminocyclopropane compound.

Molecular aggregation structure and mechanical as well as thermal properties of novel well-defined multiblock copolymers consisting of crystalline syndiotactic polystyrene (sPS) and rubbery hydrogenated polyisoprene (hPIp) were investigated. The morphology and crystalline ordered structure of the multiblock copolymer films prepared by solvent casting from 1,2-dichlorobenzene solution depended on the volume fraction of sPS (VFsPS) and number of blocks. The multiblock copolymer films exhibited ordered morphology with low crystallinity. The crystallinity of the sPS reduced with decreasing the VFsPS. The pentablock copolymer produced more ordered morphology and less crystallinity than the triblock copolymers. The anisotropic orientation and mechanical stability of the δ form sPS crystals in the spherical sPS domains during uniaxial stretching were demonstrated. Tensile testing and dynamic mechanical analysis indicated that these multiblock copolymer films with appropriate sPS fraction are strong, tough, and elastic and thus could be potential candidates for a new type of thermoplastic elastomer with discrete crystalline hard domains.