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The amination and alkenylation of the C(sp 3 )-H bond at the N -α position of secondary benzamides were both realized in this work by using N -hydroxyphthalimide (NHPI) imidate esters as substrates under a dual catalysis involving a photoredox catalyst and hydrogen atom transfer (HAT) catalyst. The developed methods significantly extended the scope of applications of the N -α position C(sp 3 )-H bond functionalization with regard to secondary N -alkylamides. More importantly, new reaction models in photoredox catalysis have been established. Based on corresponding experiments and density functional theory (DFT) calculations on the critical reaction steps combined with information reported previously, we proposed a synergistic photo- and organocatalytic reaction process for the C(sp 3 )-H bond functionalization and also clarified the occurrence of a chain process in the reaction pathway., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Despite significant advances made on the synthesis of indole derivatives through photochemical strategies during the past several years, the requirement of equivalent amounts of oxidants, bases or other additional additives has limited their practical applications in the synthesis of natural products and pharmaceuticals as environment-friendly processes. Herein, we report LED visible-light-induced redox neutral desulfonylative C(sp 2 )-H functionalization for the synthesis of N -substituted indoles with a broad scope through γ-fragmentation under mild conditions in the absence of any additional additive. The reaction mechanism paradigm has been investigated on the basis of deuterium labeling experiments, kinetic analysis, Hammett plotting analysis and DFT calculations., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Photodynamic therapy (PDT) has been rapidly developed as an effective therapeutic approach in clinical settings. However, hypoxia seriously limits the effectiveness of PDT. Here, we report a porphyrin-based metal-organic framework combined with hyaluronate-modified CaO 2 nanoparticles (PCN-224-CaO 2 -HA) to target and enhance PDT efficacy. CaO 2 reacts with H 2 O or weak acid to produce O 2 , overcoming the hypoxia problem. Hyaluronate protects CaO 2 and specifically targets the CD44 receptor, which is highly expressed on tumor cell membranes, performing targeted therapy. After PDT treatment in vitro , the survival rates of 4T1 and MCF-7 tumor cells were 14.58% and 22.45%, respectively. The fluorescence imaging showed that PCN-224-CaO 2 -HA effectively aggregated in the tumor after 12 h of its intravenous injection into tumor-bearing mice. PCN-224-CaO 2 -HA exhibited efficacious tumor growth inhibition via enhanced PDT. Overall, this nanosystem providing in situ oxygen production was successfully used for targeted PDT with a significantly enhanced therapeutic efficacy in vitro and in vivo ., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Poor ultraviolet (UV) resistance and good hydrophilicity lead to light aging of aramid fabrics and cause heat damage to the human body. This scenario occurs when the absorbed water by the fabric evaporates and forms high-temperature water vapor in a high-temperature fire environment, which may scald the human body. Herein, a superhydrophobic hollow TNT network structure was built on surfaces of aramid fibers by surface coating fluorinated TiO 2 nanotubes (TNTs) to develop an air-permeable, UV-protective, and superhydrophobic coating. The as-prepared superhydrophobic aramid fabric exhibited highly superhydrophobic properties against various solutions of sauce, coffee, methylene blue, active red, Au nanoparticles, Ag nanoparticles, HCl, and NaOH with liquid contact angles up to 152-160°. In addition, the superhydrophobic fabric exhibited excellent UV aging resistance (UV protection factor was 100+; 74.58% of strength retention for 24 h of UV radiation compared with 55.15% of untreated fabric), a self-cleaning function against solid soil, and original wearing characteristics, including good breaking strength and air permeability. The developed superhydrophobic coating technology may promote practical application in high-temperature environments for aramid fabrics due to its good UV resistance, chemical resistance, poromericity, superhydrophobicity, anti-fouling, and self-cleaning properties., Competing Interests: The authors declare that they have no competing interests., (This journal is © The Royal Society of Chemistry.)