Deoxygenative Functionalizations of Aldehydes, Ketones and Carboxylic Acids

Angewandte Chemie International Edition, Год журнала: 2021, Номер 61(10)

Опубликована: Ноя. 15, 2021

The simple and efficient conversion of carbonyl compounds into functionalized alkanes via deoxygenation is highly enabling in chemical synthesis. This Review covers the recent methodology development carboxyl deoxygenative functionalizations, highlighting some representative significant contributions this field. These advances are categorized based on reactivity patterns oxygenated feedstock compounds, including aldehydes, ketones carboxylic acids. Four types reactive intermediates arising from aldehydes during deoxygenation, namely, bis-electrophiles, carbenoids, bis-nucleophiles alkyl radical equivalents, presented, while acids mainly behave as tris-electrophiles when deoxygenated. In each subcategory, selected examples organized according to type bond formation discussed a generalized mechanistic perspective.

Язык: Английский

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Chemo‐, Stereo‐ and Regioselective Fluoroallylation/Annulation of Hydrazones with gem‐Difluorocyclopropanes via Tunable Palladium/NHC Catalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(23)

Опубликована: Апрель 4, 2023

Defluorinative manipulation of polyfluorinated molecules has shown great promise due to its granting synthetic versatility inert C-F bonds. The development chemo-, stereo- and regioselective strategies realize highly efficient formation either the linear/branched or E/Z products from gem-difluorocyclopropanes (gem-F2 CPs) is a challenging task. Herein, we have realized palladium/NHC-catalyzed fluoroallylation/annulation hydrazones with gem-F2 CPs that incorporate hydrazone N2 moiety into products. thermodynamically unstable fluorinated E-allylation aryl ketone were obtained for first time, while di-alkyl yielded monofluorinated branched selectivity under similar reaction conditions. With aldehyde hydrazones, two kinds pyrazoles via defluorinative allylation/annulation cascade, in which different carbon atoms could be incorporated pyrazole rings regiospecifically. DFT calculations revealed divergent was kinetically controlled final C-C bond proceeded through 7-membered TS.

Язык: Английский

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Photocatalytic Umpolung Strategy for the Synthesis of α-Amino Phosphine Oxides and Deuterated Derivatives

Organic Letters, Год журнала: 2023, Номер 25(44), С. 8016 - 8021

Опубликована: Окт. 30, 2023

Direct, economical, and green synthesis of deuterated α-amino phosphine oxides remains an elusive challenge in synthetic chemistry. Herein, we report a visible-light-driven umpolung strategy for synthesizing from isocyanide using 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene as the photocatalyst D2O deuterium source. Moreover, streamlined sustainable methodology can be applied modification amino acids, natural products, drugs. The strong antiproliferative activity desired products indicates that method could provide novel privileged scaffold antitumor drug development.

Язык: Английский

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Electrochemically Driven Deoxygenative Borylation of Alcohols and Carbonyl Compounds

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(31), С. 16966 - 16972

Опубликована: Июль 27, 2023

We present a new, unified approach for the transformation of benzylic and allylic alcohols, aldehydes, ketones into boronic esters under electroreductive conditions. Key to our strategy is use readily available pinacolborane, which serves both as an activator electrophile by first generating redox-active trialkylborate species then delivering desired deoxygenatively borylated product. This applicable variety substrates can be employed late-stage functionalization complex molecules.

Язык: Английский

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Umpolung reactivity of strained C–C σ-bonds without transition-metal catalysis

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Апрель 2, 2024

Abstract Umpolung is an old and important concept in organic chemistry, which significantly expands the chemical space provides unique structures. While, previous research focused on carbonyls or imine derivatives, umpolung reactivity of polarized C–C σ-bonds still needs to explore. Herein, we report reaction bicyclo[1.1.0]butanes (BCBs) with electron-deficient alkenes construct C(sp 3 )-C(sp ) bond at electrophilic position BCBs without any transition-metal catalysis. Specifically, this transformation relies strain-release driven bridging (BCBs), are emerged as ene components, providing efficient straightforward synthesis route various functionalized cyclobutenes conjugated dienes, respectively. The synthetic utilities protocol performed by several transformations. Preliminary mechanistic studies including density functional theory (DFT) calculation support concerted Alder-ene type process σ-bond cleavage hydrogen transfer. This work extends high-value structural motifs.

Язык: Английский

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Synthetic progress of organic thermally activated delayed fluorescence emitters via C–H activation and functionalization

Chemical Society Reviews, Год журнала: 2024, Номер 53(11), С. 5904 - 5955

Опубликована: Янв. 1, 2024

Thermally activated delayed fluorescence (TADF) emitters have become increasingly prominent due to their promising applications across various fields, prompting a continuous demand for developing reliable synthetic methods access them. This review aims highlight the progress made in last decade synthesizing organic TADF compounds through C-H bond activation and functionalization. The begins with brief introduction basic features design principles of emitters. It then provides an overview advantages concise development transformations constructing Subsequently, it summarizes both transition-metal-catalyzed non-transition-metal-promoted used synthesis Finally, gives outlook on further challenges potential directions this field.

Язык: Английский

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Direct carbonyl reductive functionalizations by diphenylphosphine oxide

Science Advances, Год журнала: 2025, Номер 11(6)

Опубликована: Фев. 7, 2025

Reductive functionalization of aldehydes and ketones is one the most challenging but ultimately rewarding areas in synthetic chemistry related sciences. We report a simple extremely versatile carbonyl reductive strategy achieving direct, highly selective, efficient amination, etherification, esterification, phosphinylation reactions (hetero)aryl ketones, which are or unattainable to achieve by traditional strategies, using only diphenylphosphine oxide an inorganic base. It enables modular synthesis functionally structurally diverse tertiary amines, ethers, esters, phosphine oxides, etc., as well pesticides, drug intermediates, pharmaceuticals. Compared phosphorus-mediated name reactions, this firstly transformed C═O bonds into C-element single bonds. Mechanistically, phosphinates formed undergo unconventional nucleophilic substitution at C atom within their C─O─P unit. Thus, work provides important strides field aldehydes/ketones, transformation, various fundamental reactions.

Язык: Английский

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Accessing Arenes via the Hydrodeoxygenation of Phenolic Derivatives Enabled by Hydrazine

ACS Catalysis, Год журнала: 2025, Номер 15(4), С. 3367 - 3376

Опубликована: Фев. 10, 2025

Hydrodeoxygenation (HDO) is an effective method for converting lignin and its derived phenolic compounds to value-added aromatic chemicals fuels. Efforts exploit molecular hydrogen have been made remove the hydroxyl group in lignin-derived make them appealing chemical industry. However, these processes rely on high pressure expensive catalysts, presenting challenges terms of safety, storage, cost-effectiveness. This highlights demand alternatives under more accessible reaction conditions. Herein, we present a methodology HDO phenols naphthols using Pd/C as commercial heterogeneous catalyst employing hydrazine dual reagent reducing hydrazone formation. paper presents applicable substrate scope different including pharmaceutically relevant molecules such paracetamol. Additionally, highly challenging steroid derivatives, β-estradiol, hydrodeoxygenated.

Язык: Английский

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Photo‐Induced Homologation of Carbonyl Compounds for Iterative Syntheses

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(49)

Опубликована: Окт. 13, 2022

Abstract We describe a photo‐induced reaction for the in situ generation of highly reactive alkyl diazo species from carbonyl precursors via photo‐excitation N‐tosylhydrazone anions. The intermediates undergo efficient C−H insertion aldehydes, leading to productive synthesis aldehydes and ketones. method is applicable iterative densely functionalized compounds through sequential trapping with various aldehydes. proceeds without need any catalyst by light irradiation features high functional group tolerance. More than 70 examples, some performed on gram‐scale, demonstrate broad applicability this sequence synthesis.

Язык: Английский

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The merger of vinyl-N-triftosylhydrazones and silver catalysis to enable stereoselective vinylcyclopropanation of alkenes

Chem Catalysis, Год журнала: 2022, Номер 2(3), С. 563 - 577

Опубликована: Фев. 8, 2022

Язык: Английский

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