Spinel-type LiNi0.5Mn1.5O4 porous nanorods assembled with nanoparticles have been prepared and investigated as high-rate and long-life cathode materials for rechargeable lithium-ion batteries. One-dimensional porous nanostructures of LiNi0.5Mn1.5O4 with ordered P4332 phase were obtained through solid-state Li and Ni implantation of porous Mn2O3 nanorods that resulted from thermal decomposition of the chain-like MnC2O4 precursor. The fabricated LiNi0.5Mn1.5O4 delivered specific capacities of 140 and 109 mAh g(-1) at 1 and 20 C rates, respectively. At a 5 C cycling rate, a capacity retention of 91% was sustained after 500 cycles, with extremely low capacity fade (<1%) during the initial 300 cycles. The remarkable performance was attributed to the porous 1D nanostructures that can accommodate strain relaxation by slippage at the subunits wall boundaries and provide short Li-ion diffusion distance along the confined dimension.

Dearomative cycloaddition reactions represent an ideal means of converting flat arenes into three-dimensional architectures of increasing interest in medicinal chemistry. Quinolines, isoquinolines, and quinazolines, despite containing latent diene and alkene subunits, are scarcely applied in cycloaddition reactions because of the inherent low reactivity of aromatic systems and selectivity challenges. Here, we disclose an energy transfer–mediated, highly regio- and diastereoselective intermolecular [4 + 2] dearomative cycloaddition reaction of these bicyclic azaarenes with a plethora of electronically diverse alkenes. This approach bypasses the general reactivity and selectivity issues, thereby providing various bridged polycycles that previously have been inaccessible or required elaborate synthetic efforts. Computational studies with density functional theory elucidate the mechanism and origins of the observed regio- and diastereoselectivities.

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