The 5‐heterofunctionalized triazoles are important scaffolds in bioactive compounds, but current click reactions (CuAAC) cannot produce these core structures. A copper(I)‐catalyzed interrupted click ...reaction to access diverse 5‐functionalized triazoles is reported. Various 5‐amino‐, thio‐, and selenotriazoles were readily assembled in one step in high yields. The reaction proceeds under mild conditions with complete regioselectivity. It also features a broad substrate scope and good functional group compatibility.
A copper(I)‐catalyzed interrupted click reaction to access diverse 5‐functionalized triazoles is reported. Various 5‐amino‐, 5‐thio‐, and 5‐selenotriazoles were assembled in a single step in high yields. The reaction proceeds under mild conditions with complete regioselectivity and features a broad substrate scope and compatibility with various functional groups.
As one of the most critical approaches to resolve the energy crisis and environmental concerns, carbon dioxide (CO2) photoreduction into value‐added chemicals and solar fuels (for example, CO, HCOOH, ...CH3OH, CH4) has attracted more and more attention. In nature, photosynthetic organisms effectively convert CO2 and H2O to carbohydrates and oxygen (O2) using sunlight, which has inspired the development of low‐cost, stable, and effective artificial photocatalysts for CO2 photoreduction. Due to their low cost, facile synthesis, excellent light harvesting, multiple exciton generation, feasible charge‐carrier regulation, and abundant surface sites, semiconductor quantum dots (QDs) have recently been identified as one of the most promising materials for establishing highly efficient artificial photosystems. Recent advances in CO2 photoreduction using semiconductor QDs are highlighted. First, the unique photophysical and structural properties of semiconductor QDs, which enable their versatile applications in solar energy conversion, are analyzed. Recent applications of QDs in photocatalytic CO2 reduction are then introduced in three categories: binary II–VI semiconductor QDs (e.g., CdSe, CdS, and ZnSe), ternary I–III–VI semiconductor QDs (e.g., CuInS2 and CuAlS2), and perovskite‐type QDs (e.g., CsPbBr3, CH3NH3PbBr3, and Cs2AgBiBr6). Finally, the challenges and prospects in solar CO2 reduction with QDs in the future are discussed.
Carbon dioxide (CO2) photoreduction is regarded as an attractive pathway to produce value‐added chemicals and fuels. Recent advances in CO2 photoreduction via semiconductor quantum dots (QDs) in three categories are reviewed: II–VI, I–III–VI, and perovskite‐type QDs. Additionally, current challenges and prospects for QD‐photocatalyzed CO2 reduction are discussed.
An asymmetric multicomponent, interrupted Kinugasa allylic alkylation (IKAA) reaction has been developed with a synergistic Cu‐catalyzed Kinugasa system and a Pd‐catalyzed allylic alkylation ...reaction. This unprecedented reaction provides in high yields and with high stereoselectivity a synthesis of α‐quaternary chiral β‐lactams, which cannot be produced with existing synthetic methods. Stereoselective coupling of two catalytic amounts of transient organometallic intermediates formed in situ is an important feature of this reaction.
An asymmetric multicomponent interrupted Kinugasa allylic alkylation (IKAA) reaction has been developed with a synergistic Cu‐catalyzed Kinugasa and Pd‐catalyzed allylic alkylation system. This strategy provides a high yield and highly selective synthesis of α‐quaternary chiral β‐lactams, which are not easily produced by other methods. Stereoselective coupling of two transient organometallic intermediates formed in situ is the most important feature of this reaction.
Catalytic C1 chemistry based on the activation/conversion of synthesis gas (CO+H2), methane, carbon dioxide, and methanol offers great potential for the sustainable development of hydrocarbon fuels ...to replace oil, coal, and natural gas. Traditional thermal catalytic processes used for C1 transformations require high temperatures and pressures, thereby carrying a significant carbon footprint. In comparison, solar‐driven C1 catalysis offers a greener and more sustainable pathway for manufacturing fuels and other commodity chemicals, although conversion efficiencies are currently too low to justify industry investment. In this Review, we highlight recent advances and milestones in light‐driven C1 chemistry, including solar Fischer–Tropsch synthesis, the water‐gas‐shift reaction, CO2 hydrogenation, as well as methane and methanol conversion reactions. Particular emphasis is placed on the rational design of catalysts, structure–reactivity relationships, as well as reaction mechanisms. Strategies for scaling up solar‐driven C1 processes are also discussed.
Soaking up the sun: This Review highlights recent achievements in solar‐driven C1 chemistry, especially in processes such as solar‐driven Fischer–Tropsch synthesis, the water‐gas‐shift reaction, CO2 hydrogenation, as well as CH4 and CH3OH conversion. Particular emphasis is placed on the rational design of catalysts, structure–reactivity relationships, as well as reaction mechanisms during the solar‐driven processes.
A copper(I)‐catalyzed asymmetric, three‐component interrupted Kinugasa reaction has been developed. Diverse chiral sulfur‐containing chiral β‐lactams with two consecutive stereogenic centers were ...synthesized in one step from readily available starting materials in good yields and with excellent diastereo‐ and enantioselectivity. The key is the interception of in situ formed chiral four membered copper(I) enolate intermediate with sulfur electrophiles.
A copper(I)‐catalyzed asymmetric three‐component interrupted Kinugasa reaction has been developed. Diverse chiral sulfur functional chiral β‐lactams with two consecutive stereogenic centers were synthesized in one step in good yields with excellent diastereo‐ and enantioselectivity from easily available materials.
Nitrogen‐doped porous carbon nanosheets (N‐CNS) are synthesized by hydrothermal carbon coating of g‐C3N4 nanosheets followed by high‐temperature treatment in N2. g‐C3N4 serves as a template, nitrogen ...source, and porogen in the synthesis. This approach yields N‐CNS with a high nitrogen content and comparable oxygen reduction reaction catalytic activities to commercial Pt/C catalysts in alkaline media.
Efficient capture of solar energy will be critical to meeting the energy needs of the future. Semiconductor photocatalysis is expected to make an important contribution in this regard, delivering ...both energy carriers (especially H2) and valuable chemical feedstocks under direct sunlight. Over the past few years, carbon dots (CDs) have emerged as a promising new class of metal‐free photocatalyst, displaying semiconductor‐like photoelectric properties and showing excellent performance in a wide variety of photoelectrochemical and photocatalytic applications owing to their ease of synthesis, unique structure, adjustable composition, ease of surface functionalization, outstanding electron‐transfer efficiency and tunable light‐harvesting range (from deep UV to the near‐infrared). Here, recent advances in the rational design of CDs‐based photocatalysts are highlighted and their applications in photocatalytic environmental remediation, water splitting into hydrogen, CO2 reduction, and organic synthesis are discussed.
Carbon dots (CDs) have emerged as promising materials for various photocatalytic reactions owing to their tunable light‐harvesting range and outstanding electron‐transfer efficiency stemming from their intrinsic nanostructures. Recent advances in the rational design of CD‐based photocatalysts and their applications in photocatalytic environmental remediation, hydrogen evolution by water splitting, CO2 reduction, and organic synthesis are highlighted.
Dinitrogen reduction to ammonia using transition metal catalysts is central to both the chemical industry and the Earth's nitrogen cycle. In the Haber-Bosch process, a metallic iron catalyst and high ...temperatures (400 °C) and pressures (200 atm) are necessary to activate and cleave NN bonds, motivating the search for alternative catalysts that can transform N
to NH
under far milder reaction conditions. Here, the successful hydrothermal synthesis of ultrathin TiO
nanosheets with an abundance of oxygen vacancies and intrinsic compressive strain, achieved through a facile copper-doping strategy, is reported. These defect-rich ultrathin anatase nanosheets exhibit remarkable and stable performance for photocatalytic reduction of N
to NH
in water, exhibiting photoactivity up to 700 nm. The oxygen vacancies and strain effect allow strong chemisorption and activation of molecular N
and water, resulting in unusually high rates of NH
evolution under visible-light irradiation. Therefore, this study offers a promising and sustainable route for the fixation of atmospheric N
using solar energy.
Inherent poor stability of perovskite nanocrystals (NCs) is the main impediment preventing broad applications of the materials. Here, TiO2 shell coated CsPbBr3 core/shell NCs are synthesized through ...the encapsulation of colloidal CsPbBr3 NCs with titanium precursor, followed by calcination at 300 °C. The nearly monodispersed CsPbBr3/TiO2 core/shell NCs show excellent water stability for at least three months with the size, structure, morphology, and optical properties remaining identical, which represent the most water‐stable inorganic shell passivated perovskite NCs reported to date. In addition, TiO2 shell coating can effectively suppress anion exchange and photodegradation, therefore dramatically improving the chemical stability and photostability of the core CsPbBr3 NCs. More importantly, photoluminescence and (photo)electrochemical characterizations exhibit increased charge separation efficiency due to the electrical conductivity of the TiO2 shell, hence leading to an improved photoelectric activity in water. This study opens new possibilities for optoelectronic and photocatalytic applications of perovskites‐based NCs in aqueous phase.
TiO2 shell coated CsPbBr3 core/shell nanocrystals are successfully constructed, resulting in excellent water, photo and thermal stability. TiO2 shell coating effectively increases charge separation efficiency, hence leading to an improved photoelectric activity in water.
Semiconductor photocatalysis attracts widespread interest in water splitting, CO2 reduction, and N2 fixation. N2 reduction to NH3 is essential to the chemical industry and to the Earth's nitrogen ...cycle. Industrially, NH3 is synthesized by the Haber–Bosch process under extreme conditions (400–500 °C, 200–250 bar), stimulating research into the development of sustainable technologies for NH3 production. Herein, this study demonstrates that ultrathin layered‐double‐hydroxide (LDH) photocatalysts, in particular CuCr‐LDH nanosheets, possess remarkable photocatalytic activity for the photoreduction of N2 to NH3 in water at 25 °C under visible‐light irradiation. The excellent activity can be attributed to the severely distorted structure and compressive strain in the LDH nanosheets, which significantly enhances N2 chemisorption and thereby promotes NH3 formation.
Layered‐double‐hydroxide (LDH) nanosheets are shown to exhibit outstanding visible‐light‐driven photocatalytic activity for the reduction of N2 to NH3 under ambient conditions. Irradiation of CuCr‐LDH nanosheets in N2‐saturated water with 500 nm monochromatic light produces NH3. The excellent activity can be attributed to the severely distorted structure and compressive strain of the LDH nanosheets, promoting NH3 formation.
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