Bond-Forming and -Breaking Reactions at Sulfur(IV): Sulfoxides, Sulfonium Salts, Sulfur Ylides, and Sulfinate Salts

Chemical Reviews, Год журнала: 2019, Номер 119(14), С. 8701 - 8780

Опубликована: Июнь 25, 2019

Organosulfur compounds have long played a vital role in organic chemistry and the development of novel chemical structures architectures. Prominent among these organosulfur are those involving sulfur(IV) center, which been subject countless investigations over more than hundred years. In addition to list textbook sulfur-based reactions, there has sustained interest organosulfur(IV) recent Of particular within is ease with synthetic chemist can effect wide range transformations through either bond formation or cleavage at sulfur. This review aims cover developments past decade molecules provide insight into both reactions critically rely on this versatile element diverse scaffolds that thereby be synthesized.

Язык: Английский

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Electrochemical Oxidative Cross-Coupling with Hydrogen Evolution Reactions

Accounts of Chemical Research, Год журнала: 2019, Номер 52(12), С. 3309 - 3324

Опубликована: Ноя. 27, 2019

Oxidative cross-coupling has proved to be one of the most straightforward strategies for forming carbon-carbon and carbon-heteroatom bonds from easily available precursors. Over past two decades, tremendous efforts have been devoted in this field significant advances achieved. However, order remove surplus electrons substrates chemical formation, stoichiometric oxidants are usually needed. Along with development modern sustainable chemistry, considerable perform oxidative reactions under external-oxidant-free conditions. Electrochemical synthesis is a powerful environmentally benign approach, which can not only achieve cross-couplings conditions, but also release valuable hydrogen gas during bond formation. Recently, electrochemical evolution significantly explored. This Account presents our recent toward reactions. (1) We explored thiols/thiophenols arenes, heteroarenes, alkenes C-S (2) Using strategy C-H/N-H evolution, we successfully realized C-H amination phenols, anilines, imidazopyridines, even ethers. (3) Employing halide salts as green halogenating reagents, developed clean halogenation protocol oxidation To address limitation that reaction had carry out aqueous solvent, an alternative method uses CBr4, CHBr3, CH2Br2, CCl3Br, CCl4 reagents mixture acetonitrile methanol cosolvent. (4) approach constructing C-O well-developed manner. (5) Under mild C(sp2)-H C(sp3)-H phosphonylation modest high yields. (6) achieved S-H/S-H By anodic instead oxidants, overoxidation thiols thiophenols was well avoided. (7) The methods structurally diverse heterocyclic compounds were via annulations. (8) applied difunctionalization multiple step, such C-S/C-O bonds, C-S/C-N C-Se/C-O C-Se/C-N bonds. hope studies will stimulate research interest chemists pave way discovery more

Язык: Английский

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Electroreductive Carbofunctionalization of Alkenes with Alkyl Bromides via a Radical-Polar Crossover Mechanism

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(49), С. 20661 - 20670

Опубликована: Ноя. 24, 2020

Electrochemistry grants direct access to reactive intermediates (radicals and ions) in a controlled fashion toward selective organic transformations. This feature has been demonstrated variety of alkene functionalization reactions, most which proceed via an anodic oxidation pathway. In this report, we further expand the scope electrochemistry reductive alkenes. particular, strategic choice reagents reaction conditions enabled radical-polar crossover pathway wherein two distinct electrophiles can be added across highly chemo- regioselective fashion. Specifically, used strategy intermolecular carboformylation, anti-Markovnikov hydroalkylation, carbocarboxylation alkenes—reactions with rare precedents literature—by means electroreductive generation alkyl radical carbanion intermediates. These reactions employ readily available starting materials (alkyl halides, alkenes, etc.) simple, transition-metal-free display broad substrate good tolerance functional groups. A uniform protocol achieve all three transformations by simply altering medium. development provides new avenue for constructing Csp3–Csp3 bonds.

Язык: Английский

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Anodic Oxidation for the Stereoselective Synthesis of Heterocycles

Accounts of Chemical Research, Год журнала: 2019, Номер 53(1), С. 105 - 120

Опубликована: Дек. 24, 2019

ConspectusStereodefined aliphatic heterocycles are one of the fundamental structural motifs observed in natural products and biologically active compounds. Various strategies for synthesis these building blocks based on transition metal catalysis, organocatalysis, noncatalytic conditions have been developed. Although electrosynthesis has also utilized functionalization heterocycles, stereoselective transformations under electrochemical still a challenging field electroorganic chemistry.This Account consists four main topics related to our recent efforts diastereo- and/or enantioselective especially N-heterocycles, using anodic oxidations as key steps. The first topic is development synthetic methods multisubstituted piperidines pyrrolidines from anodically prepared α-methoxy cyclic amines. Our were primarily N-acyliminium ion chemistry, diastereoselective methoxylation, arylation, deallylative methoxylation. Furthermore, we found unique property N-cyano protecting group that enabled α-methoxylation α-substituted second investigation memory chirality decarboxylative We methoxylation oxazolidine thiazolidine derivatives with appropriate N-protecting occurred stereospecific manner even though reaction proceeded through an sp2 planar carbon center. findings demonstrated example chemistry. third chiral azabicyclo-N-oxyls their application organocatalysis oxidative kinetic resolution secondary alcohols. final utilizing generated halogen cations. investigated amino alcohol bromo developed intramolecular C–C bond formation keto amides, bromoiminolactonization α-allyl malonamides, ring expansion allyl It noteworthy most reactions performed undivided cells constant-current conditions, which avoided complicated setup was beneficial large-scale reaction. In addition, some challenges hope research will contribute further construction valuable heterocyclic compounds approach.

Язык: Английский

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Multicomponent reactions and photo/electrochemistry join forces: atom economy meets energy efficiency

Chemical Society Reviews, Год журнала: 2022, Номер 51(6), С. 2313 - 2382

Опубликована: Янв. 1, 2022

Visible-light photoredox catalysis has been regarded as an extremely powerful tool in organic chemistry, bringing the spotlight back to radical processes. The versatility of photocatalyzed reactions already demonstrated be effective providing alternative routes for cross-coupling well multicomponent reactions. photocatalyst allows generation high-energy intermediates through light irradiation rather than using highly reactive reagents or harsh reaction conditions. In a similar vein, electrochemistry experienced fruitful renaissance generating without need any catalyst. Such milder approaches pose basis toward higher selectivity and broader applicability. electrochemical reactions, species acts starter cascade events. This diverse reactivity use is usually not covered by classical methods. Owing availability cheaper more standardized photo- reactors, easily scalable flow-setups, it surprising that these two fields have become areas increased research interest. Keeping view, this review aimed at overview synthetic design MCRs involving and/or activation crucial step with particular focus on choice difunctionalized reagent.

Язык: Английский

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Reticular Synthesis of tbo Topology Covalent Organic Frameworks

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(38), С. 16346 - 16356

Опубликована: Авг. 25, 2020

The metal–organic framework (MOF) HKUST-1 with a tbo topology serves as an archetypal tunable and isoreticular platform for targeting desired applications, but the design synthesis of tbo-covalent organic frameworks (COFs) remains formidable challenge. Here we demonstrate successful use reticular chemistry appropriate strategy deliberate construction COFs topology. judicious selection perquisite planar building blocks, 4-connected square tetramine porphyrin 3-connected trigonal trialdehydes triphenylamine, allows condensation two tbo-COFs, first examples resulting both crystallize in cubic Pm3̅ space group adopt non-interpenetrated open framework, which each tritopic linker connects to three units forming truncated Td-octahedron occupies alternating triangular faces octahedron. Owing presence different types photoredox-active moieties, can be efficient heterogeneous photocatalysts oxidative hydroxylation arylboronic acids reductive defluoroalkylation trifluoromethyl aromatics alkenes. present finding will provide impetus examine potential tbo-COFs new engineering multifunctional materials via expansion functionalization blocks.

Язык: Английский

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Recent Advances on the Electrochemical Difunctionalization of Alkenes/Alkynes

Chinese Journal of Chemistry, Год журнала: 2019, Номер 37(3), С. 292 - 301

Опубликована: Фев. 6, 2019

Electroorganic synthesis is an emerging area of high impact research in organic chemistry, which considered as one the green and efficient methods attracts growing attention. In this review, we summarized comprehensively recent literature reports on electrochemical oxidative difunctionalization unsaturated C—C bonds. The reaction types described review included intermolecular cyclization, intramolecular alkenes/alkynes. This focuses discussion its synthetic generality for preparation functionalized compounds related mechanism.

Язык: Английский

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Recent developments in the difunctionalization of alkenes with C–N bond formation

Organic Chemistry Frontiers, Год журнала: 2021, Номер 8(18), С. 5206 - 5228

Опубликована: Янв. 1, 2021

Various alkene difunctionalization reactions involving nitridization, diamination, azidation, oxyamination, carboamination, aminohalogenation, and nitration are introduced in this review.

Язык: Английский

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Recent advances in transition metal-mediated trifluoromethylation reactions

Chemical Communications, Год журнала: 2022, Номер 58(75), С. 10442 - 10468

Опубликована: Янв. 1, 2022

Fluorine compounds are known for their abundance in more than 20% of pharmaceutical and agrochemical products mainly due to the enhanced lipophilicity, metabolic stability pharmacokinetic properties organofluorides. Consequently, last decade has seen enormous growth incorporation a trifluoromethyl group into organic motifs. With significance, this review aims provide complete picture transition metal-mediated construction C(sp3, sp2, sp)-CF3 bonds via C-H/X bond functionalization or addition processes both aliphatic aromatic hydrocarbons. Diversified reagents ranging from radical electrophilic nucleophilic trifluoromethylating agents respective mechanisms have been further deliberated comprehensive overview. The coverage on topic is expected make unique beneficial future applications enriching community towards improvements field trifluoromethylation reactions, turn improving propensity development drugs.

Язык: Английский

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Organoselenium Compounds: Chemistry and Applications in Organic Synthesis

Chemistry - A European Journal, Год журнала: 2023, Номер 29(52)

Опубликована: Июнь 28, 2023

Abstract Selenium, originally described as a toxin, turns out to be crucial trace element for life that appears selenocysteine and its dimer, selenocystine. From the point of view drug developments, selenium‐containing drugs are isosteres sulfur oxygen with advantage presence selenium atom confers antioxidant properties high lipophilicity, which would increase cell membrane permeation leading better oral bioavailability. In this article, we have focused on relevant features atom, above all, corresponding synthetic approaches access variety organoselenium molecules along proposed reaction mechanisms. The preparation biological selenosugars, including selenoglycosides, selenonucleosides, selenopeptides, other compounds will treated. We attempted condense most important aspects interesting examples chemistry into single article.

Язык: Английский

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