Ultrastrong and Hydrophobic Sandwich-Structured MXene-Based Composite Films for High-Efficiency Electromagnetic Interference Shielding.

Electromagnetic interference (EMI) shielding materials are highly necessary to solve the problem of electromagnetic radiation. Transition-metal carbide/nitride (MXene) materials offer great potential for the construction of high-performance EMI shields because of their high electrical conductivity and versatile surface chemistry. However, MXene generally suffers from poor mechanical and oxidation-resistant properties, which hinders its practical applications.

TfO-Mediated Cyclization of α-Acyl-β-(2-aminopyridinyl)acrylamides: Access to N-Substituted 4-Pyrido[1,2-]pyrimidin-4-imines.

A facile and efficient direct synthesis of N-substituted 4-pyrido[1,2-]pyrimidin-4-imines is developed from α-acyl-β-(2-aminopyridinyl)acrylamides mediated by triflic anhydride (TfO) in the presence of 2-chloropyridine. This amide activation protocol features mild reaction conditions, simple execution, excellent yields, and high chemoselectivity, and is also applied to the synthesis of substituted 4-pyrido[1,2-]pyrimidin-4-ones via a practical one-pot procedure.

Smart mesoporous silica nanoparticles gated by pillararene-modified gold nanoparticles for on-demand cargo release.

A new drug delivery system, based on mesoporous silica nanoparticles gated by carboxylatopillar[5]arene-modified gold nanoparticles, has been fabricated, which demonstrated good responses to competitive binding and temperature variation. This multifunctional nanosystem combines the excellent characteristics of two kinds of nanoparticles and utilizes a supramolecular host-guest approach for on-demand cargo release.