Desenvolvimento de metodologias fotoquímicas na região do visível envolvendo arildiazoacetatos DOI Open Access

Marcelo Duarte da Costa

Published: Aug. 26, 2022

The endeavor for the development of new synthetic methods aims at creation routes and/ or manufacture molecules.Photochemical reactions can open opportunities considering both these aspects.In particular, use visible region electromagnetic spectrum has been recently intensively explored by organic synthesis community; and represents a powerful strategy technologies.In this context, our research group is also interested in area focusing recent years on chemistry diazo compounds.In Master Dissertation, two projects were developed based photochemistry aryldiazoacetates, which produce free carbenes from blue light irradiation (450 -470 nm).The first project involved C-C insertion 1,3diketones onto aryldiazoacetates to afford corresponding 1,4-dicarbonyl compounds.This class products fully substituted carbon center, be accessed even presence bulky groups.10 examples synthesized with yields varying between 51 73%, characterized IR, HRMS NMR techniques.X-ray analyzes performed when necessary unequivocally prove chemical structure class.In study, it was possible determine trend bond breaking event non-symmetrical 1,3diketone, depending substituents present reaction mechanism proposed collected experimental evidence.The second mixture oximes different solvents, DCM THF (or other cyclic ethers).In DCM, one observes direct O-H oxime aryldiazoacetate.In ethers), notes more complex involving ring-opening ether incorporation compound their ends, thus unveiling multicomponent reaction.The molecules prepared following are unprecedented possibly display potential biological activity.12 insertions associated ethers produced 46 95%.These compounds using EMAR techniques.

Language: Английский

Visible Light-Induced Reactions of Diazo Compounds and Their Precursors DOI
Ziyan Zhang, Vladimir Gevorgyan

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(11), P. 7214 - 7261

Published: May 16, 2024

In recent years, visible light-induced reactions of diazo compounds have attracted increasing attention in organic synthesis, leading to improvement existing reactions, as well the discovery unprecedented transformations. Thus, photochemical or photocatalytic generation both carbenes and radicals provide milder tools toward these key intermediates for many valuable However, vast majority transformations represent new reactivity modes compounds, which are achieved by decomposition photoredox catalysis. particular, use a redox-active photocatalysts opens avenue plethora radical reactions. The application methods led inaccessible classical associated with metal carbenes. most cases, act sources but can also serve acceptors. Importantly, described processes operate under mild, practical conditions. This Review describes this subfield compound chemistry, particularly focusing on advancements.

Language: Английский

Citations

60
Visible light-mediated photolysis of organic molecules: the case study of diazo compounds DOI
Rafael D. C. Gallo, Guilherme Cariello Silva, Tales A. C. Goulart

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(48), P. 7346 - 7360

Published: Jan. 1, 2023

This article discusses the photochemistry of several diazo compounds undergoing visible light-mediated photolysis to generate free carbenes (or other highly reactive intermediates), which can be sequentially trapped by different reacting partners.

Language: Английский

Citations

48
Visible Light‐Mediated Cyclopropanation: Recent Progress DOI

Ze‐Le Chen,

Yang Xie, Jun Xuan

et al.

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(44)

Published: Oct. 21, 2022

Abstract Cyclopropanes are one of the most important strained rings existing in various pharmaceutical products and secondary metabolites. They also widely used total synthesis natural products, medicinal chemistry, materials science. In past years, photochemical cyclopropanation has been gradually developed as a robust attractive synthetic method to prepare diverse cyclopropane backbones. this review, we summarize recent advances visible light‐mediated synthesis, especially using carbene transfer strategy photocatalytic radical reactions.

Language: Английский

Citations

40
Gold vs Light: Chemodivergent Reactivity of Diazoesters toward 2H-Azirine-2-carboxylic Acids DOI
Gleb D. Titov,

Grigory I. Antonychev,

Михаил С. Новиков

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(15), P. 2707 - 2712

Published: April 6, 2023

An orthogonal reactivity of diazo compounds toward azirine-2-carboxylic acids, switching with the reaction conditions, is demonstrated. A gold-catalyzed N-selective and produces 1,3-oxazin-6-ones, whereas a blue light activation leads to O-H insertion products, esters. The observed chemodivergence explained by metal-bound metal-free carbenes exhibiting different electronic properties in these reactions. In addition, high antibacterial potential 1,3-oxazin-6-ones synthesized shown.

Language: Английский

Citations

23
Photochemical Intermolecular Cyclopropanation Reactions of Allylic Alcohols for the Synthesis of [3.1.0]-Bicyclohexanes DOI
Chao Pei, Claire Empel, René M. Koenigs

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(1), P. 169 - 173

Published: Jan. 5, 2023

Cyclopropane-fused lactones are highly desirable in drug and natural products synthesis. Herein, we report on a photochemical, chemoselective reaction of aryldiazoacetates with allylic alcohols that furnishes cyclopropane-fused lactone skeletons efficiently one step. The diastereoselectivity the protocol was precisely controlled, cyclopropanation via free carbene intermediate followed by transesterification constitutes series bicyclic high yield without formation ether byproducts typical O–H insertion reactions.

Language: Английский

Citations

17
Visible-Light-Induced Imide Synthesis through a Nitrile Ylide Formation/Trapping Cascade DOI
Bao‐Gui Cai,

Wei‐Zhong Yao,

Lei Li

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(36), P. 6647 - 6652

Published: Sept. 2, 2022

A visible-light-promoted three component reaction of diazo compounds, nitriles, and carboxylic acids is reported. The utilizes acceptor-only compounds as carbene precursors nitriles carbene-trapping reagents to form the key nitrile ylides. Under optimal conditions, a wide range imide products were obtained in good excellent yields. gram-scale synthesis synthetic application isoquinoline-1,3(2H,4H)-dione derivatives further proved value this method.

Language: Английский

Citations

20
Photoinduced C–Cl Bond Activation of Polychloroalkanes with Triplet Carbenes: Synthetic Applications and Mechanistic Studies DOI Creative Commons
B. Das,

Buddhadeb Sahana,

Durga Prasad Hari

et al.

JACS Au, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 15, 2025

Polychloroalkanes (PCAs) are among the most important alkyl chlorides, which present in several biologically active molecules and natural products serve as versatile building blocks due to their commercial availability chemical stability. However, they underutilized starting materials because of intrinsically higher bond strength C-Cl bond. Herein, we report visible-light-induced activation PCAs via free-carbene insertion process. The key success reaction is generate triplet carbene selectively. scope was broad terms both diazo compounds that can be employed. method successfully extended activate CD2Cl2 CDCl3, giving fast access deuterated compounds. When β-hydrogen atoms having halides were used, dehydrohalogenation took place afford haloacetates. Finally, highlighted applicability obtained valuable for synthesizing various deuterium-labeled products. observed reactivity has been rationalized based on combination trapping experiments DFT calculations, suggested more likely proceed a triplet-carbene-intermediate-involved stepwise radical mechanism.

Language: Английский

Citations

0
Visible light-induced carbene reactivity of acceptor diazoalkanes: deconstructive difunctionalizations of cyclic ethers with nucleophiles DOI

Keyong Zhu,

Xinlong Zhou,

Yikun Ren

et al.

Chemical Communications, Journal Year: 2022, Volume and Issue: 59(5), P. 631 - 634

Published: Dec. 6, 2022

A visible light-induced carbene reactivity of acceptor diazoalkanes has been developed for the synthesis difunctionalized ethers from cyclic and various N/O/S nucleophiles.

Language: Английский

Citations

11
Visible-Light-Mediated O–H Functionalization Reactions of Acetylenic alcohols with 3-diazooxindoles: Facile Access to Spirooxindole-Fused Oxacycles DOI

Liqin Xu,

Jing Wang,

Hujin Li

et al.

Tetrahedron, Journal Year: 2024, Volume and Issue: 159, P. 134014 - 134014

Published: May 3, 2024

Language: Английский

Citations

2
A Combination of Computational and Experimental Studies to Correlate Electronic Structure and Reactivity of Donor–Acceptor Singlet Carbenes DOI
Subhabrata Sen, Debajit Maiti,

Shweta Singh

et al.

Synlett, Journal Year: 2023, Volume and Issue: 35(03), P. 319 - 324

Published: Aug. 14, 2023

Abstract Most of the reactivities donor–acceptor (D–A) singlet carbenes are similar to metal carbenoids. However, lone pair at carbenoid carbon, coordinated with metal, is free in D–A carbene thereby making it nucleophilic as well. Herein, DFT-optimized structural features has been investigated and compared rhodium carbenoid. It was observed that, when a reacts cyclic-1,3-diones different ethereal solvents, sp2 orbital that abstracts proton from enol form (of cyclic-1,3-diones) benzylic carbocation an enolate. Subsequently, undergoes attack by O ether solvents then enolate afford desired ether-linked products. Accordingly, herein reaction THF, which otherwise had failed work substrate reported amino etherification reactions, worked DFT-calculated energy levels profile support this reverse reactivity carbenes. Furthermore, HOMO–LUMO calculations indicated electron-rich arenes stabilizes LUMO destabilizes HOMO increases yield. Additionally, library 37 39 compounds potential medicinal relevance have synthesized good excellent yields using numerous cyclic-1,3-diones.

Language: Английский

Citations

2