In this communication,we disclose the first example of metal-free and site-selective radical fluorination of readily available tertiary alkyl ethers,enabled by synergistic photocatalysis and organocatalysis.This catalytic combination allows for exclusive fluorination of tertiary C–O bonds under mild conditions even in the presence of competing reaction sites.The excellent functional group tolerance affords valuable access to sterically hindered alkyl fluorides through late-stage modification of complex molecules.The successful use of tertiary alkyl ethers in radical fluorination enhances the structural diversity of aliphatic fluorides that can be derived from naturally abundant alcohols. 相似文献
A Brønsted acid-catalyzed asymmetric Friedel–Crafts alkylation of 3-indolylsulfamidates with indoles has been established toward the efficient synthesis of biologically important bisindolylarylmethane derivatives containing the phenylsulfamate group. The reaction using chiral BINOL-derived phosphoric acid as the catalyst was tolerant to a diverse range of 3-indolylsulfamates and indoles, and provided for the first time bisindolylarylmethane sulfamate derivatives in good yields and with moderate to high enantioselectivities (up to 89% yield, 94:6 er). Moreover, some of these novel compounds were evaluated for their biological activities and confirmed to show bioactivity for preventing peripheral nerve degeneration. 相似文献
Photoresponsive molecular systems are essential for molecular optoelectronic devices, but most molecular building blocks are non‐photoresponsive. Employed here is a photoinduced proton transfer (PIPT) strategy to control charge transport through single‐molecule azulene junctions with visible light under ambient conditions, which leads to a reversible and controllable photoresponsive molecular device based on non‐photoresponsive molecules and a photoacid. Also demonstrated is the application of PIPT in two single‐molecule AND gate and OR gate devices with electrical signal as outputs. 相似文献
Science China Chemistry - Destructive quantum interference (DQI) provides a unique approach to controlling the leakage current in the OFF state of molecular devices. However, the DQI in... 相似文献
The authors describe an amperometric sensor for dopamine (DA) by employing olive-like Fe2O3 microspheres (OFMs) as the electrocatalyst for DA oxidization. The OFMs were prepared by using a protein templated method. The structure and properties of the OFMs were characterized by scanning electron microscopy, X-ray powder diffraction, energy dispersive x-ray spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The OFMs possess excellent catalytic activity towards DA oxidization due to their unique morphology. The sensor responds to DA within less than 5 s. The sensor, best operated at a voltage of +0.2 V (vs. SCE) responds linearly in the 0.2 to 115 μM DA concentration range and has a 30 nM detection limit. The selectivity, reproducibility and long-term stability of the sensor are acceptable. It performs well when applied to spiked human urine samples.
Graphical abstract Olive-like Fe2O3 microspheres (OFMs), synthesized using egg white as template, display excellent catalytic activity towards dopamine (DA) oxidization due to their unique morphology. They were applied for DA detection using the amperometric technique. The electrochemical sensor exhibited a high sensitivity and a 30 nM detection limit. DAQ: dopaquinone.