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Covalent organic frameworks (COF) with periodic porous structures and tunable functionalities are a new class of crystalline polymers connected via strong covalent bonds. Constructing COF materials with high stability and porosity is attracting and essential for COFs' further functional exploration. In this work, two new covalent organic frameworks (TTA-TMTA-COF and TTA-FMTA-COF) with high surface area, large pore volume, and excellent chemical stability toward harsh conditions are designed and synthesized by integrating the methoxy functional groups into the networks. Both two COFs are further employed for iodine removal since radioactive iodine in nuclear waste has seriously threatened the natural environment and human health. TTA-TMTA-COF and TTA-FMTA-COF can capture 3.21 and 5.07 g g -1 iodine, respectively. Notably, the iodine capture capacity for iodine of TTA-FMTA-COF does not show any decline after being recycled five times. These results demonstrate both COFs possess ultrahigh capacity and excellent recyclability., (© 2021 Wiley-VCH GmbH.)

A silver-catalyzed chemoselective [4+2] annulation of aryl and heteroaryl isocyanides with α-substituted isocyanoacetamides was developed for the facile and efficient synthesis of 2-aminoquinolones, naphthyridines, and phenanthrolines. A mechanism for this multistep domino reaction is proposed on the basis of a 13 C-labeling experiment, according to which an unprecedented chemoselective heterodimerization of two different isocyanides generates an α-amidoketenimine intermediate, which undergoes 1,3-amino migration to form an α-imidoylketene, followed by 6 π electrocyclization., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)