Dual-catalyst engineered porous organic framework for visible-light triggered, metal-free and aerobic sp3 C H activation in highly synergistic and recyclable fashion
作者:Gaurav Kumar、Soumya Ranjan Dash、Subhadip Neogi
DOI:10.1016/j.jcat.2020.12.013
日期:2021.2
visible-light triggered oxidativeMannichreaction to produce biorelevant heterocycle β-amino ketone in excellent yield at room temperature, using oxygen as clean and selective oxidant. Importantly, activity of this bi-functionalized catalyst compares favorably well to individual homogeneous counterparts. The covalently modified framework demonstrates economic viability via gram-scale synthesis besides
光氧化还原和有机催化代表了新型碳-碳键的强大构建工具,在温和的条件下,两种方法在单个可回收平台上的精细融合可在环境下产生协同和生态友好的反应。旨在基于烯胺的光氧化还原催化原子经济和无金属的sp 3 C H活化,设计了一种基于酰胺的二维(2D)多孔有机骨架(POF)。下垂的NH 2各组明智地锚定有两个催化站。玫瑰孟加拉和L-脯氨酸,通过逐步改变固相肽合成。双催化剂工程化的POF代表一种完全有机的材料,它可以在室温下协同地执行可见光触发的氧化曼尼希反应,以氧气的清洁和选择性氧化剂的优异收率生产生物相关的杂环β-氨基酮。重要的是,这种双官能化催化剂的活性与单独的均相对应物相比非常好。共价修饰的框架除具有令人称赞的可重复使用性外,还通过克级合成证明了经济可行性,并被证明对19种底物有效。根据实验和理论研究,详细说明了从主体聚合物到底物的有效能量转移的光催化路径,这为光有机结合机理提供了概念验证。除
Carbazole–triazine based donor–acceptor porous organic frameworks for efficient visible-light photocatalytic aerobic oxidation reactions
作者:Jian Luo、Jingzhi Lu、Jian Zhang
DOI:10.1039/c8ta05329d
日期:——
synthesis of a series of carbazole–triazine based donor–acceptor (D–A) POFs and their photocatalytic activities for aerobicoxidation reactions. The simultaneous introduction of a carbazole-based electron donor and a triazine-based electron acceptor in D–A POFs stabilizes the charge transfer state and enables an efficient triplet–triplet energy transfer to generate 1O2. Meanwhile, systematic variation of
我们报告了一系列基于咔唑-三嗪的供体-受体(DA)POF的合成及其对需氧氧化反应的光催化活性。在D–A POF中同时引入咔唑基电子供体和三嗪基电子受体可稳定电荷转移状态,并能有效地进行三重态-三重态能量转移,从而产生1 O 2。同时,D–A距离的系统变化导致可调节的光氧化还原特性,因此产生了活性氧(ROSs)的效率。在可见光激发下,所有三种D–A POF均具有出色的促进三种需氧氧化的能力:硫化物氧化,氧化胺偶联和曼尼希反应。这项系统的研究验证了D–A POF作为高性能光氧化催化剂的设计原理,该催化剂具有广泛的底物范围以及出色的稳定性和可回收性。
Aerobic Oxidative Mannich Reaction Promoted by Catalytic Amounts of Stable Radical Cation Salt
A catalytic amount of triarylaminium salt is demonstrated to be an efficient initiator for oxidative Mannich reaction of tertiary amines and nonactivated ketones under mild neutral conditions. Air is essential for this reaction and acts as a terminal oxidant. Metal catalysts, acid or base additives, and stoichiometric amounts of chemical oxidants are all avoided in this methodology. Six examples of
Porphyrin-Metalation-Mediated Tuning of Photoredox Catalytic Properties in Metal–Organic Frameworks
作者:Jacob A. Johnson、Jian Luo、Xu Zhang、Yu-Sheng Chen、Martha D. Morton、Elena Echeverría、Fernand E. Torres、Jian Zhang
DOI:10.1021/acscatal.5b00941
日期:2015.9.4
yet their utilization toward organic transformations has been limited. Here we describe the preparation and synthetic applications of four isostructural porphyrinic MOFs, namely, UNLPF-10a, -10b, -11, and -12, which are composed of free base, InIII-, SnIVCl2-, and SnIV-porphyrin building blocks, respectively. We demonstrate that the metalation with high valent metal cations (InIII and SnIV) significantly
通过单电子转移过程对有机分子进行光氧化还原催化活化已被证明是一种温和而有效的合成方法。但是,对昂贵的钌和铱配合物的严重依赖限制了它们在大规模合成中的应用。为此,作为新型异质光催化体系,光活性金属有机骨架(MOF)表现出独特的优势,但其在有机转化中的利用受到限制。在这里,我们描述了由游离碱,In III-,Sn IV Cl 2-和Sn IV组成的四种同结构的卟啉MOF(即UNLPF-10a,-10b,-11和-12)的制备和合成应用。-卟啉积木。我们证明了高价金属阳离子(III和Sn IV)的金属化显着修饰了卟啉大环的电子结构,并提供了高度氧化的光激发态,可以进行有效的还原淬灭过程以促进有机反应。特别是,UNLPF-12对一系列重要的有机转化,包括芳基硼酸的需氧羟基化,胺偶联和曼尼希反应,均表现出出色的光稳定性和有效的光催化活性。
Donor-acceptor type [4+3] covalent organic frameworks: sub-stoichiometric synthesis and photocatalytic application
Three unprecedented2D [4+3] covalentorganicframeworks (TTCOF-1, TTCOF-2, and TTCOF-3) have been prepared by substoichiometric condensation of tetratopic and tritopic monomers, overcoming the limitations of the design rules of conventional topologies. By reticulating the tetraphenylethylene (TPE)-based and triazine-based moieties into COF frameworks, novel electron donor-acceptor (D-A) type structures