Photoredox-Catalyzed α-Sulfonylation of Ketones from Sulfur Dioxide and Thianthrenium Salts

Organic Letters, Journal Year: 2022, Volume and Issue: 24(15), P. 2955 - 2960

Published: April 13, 2022

A photoredox-catalyzed sulfonylation of silyl enol ethers with DABCO·(SO2)2 and thianthrenium salts is achieved, providing diverse β-keto sulfones in moderate to good yields. This protocol features easily accessible starting materials functional group compatibility, enabling the introduction various functionalized sulfonyl groups into ketones. Furthermore, as one important industrial raw materials, methanol can be employed methyl source prepare α-methylsulfonated ketones through a intermediate for first time.

Language: Английский

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An iron-catalyzed multicomponent reaction of cycloketone oxime esters, alkenes, DABCO·(SO₂)₂ and trimethylsilyl azide

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(4), P. 917 - 922

Published: Jan. 1, 2022

The synthesis of β-azidosulfones starting from alkenes, cycloketone oxime esters, trimethylsilyl azide and a sulfur dioxide surrogate DABCO·(SO 2 ) under iron catalysis is developed.

Language: Английский

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Recent Advances in Cyclization Reactions of 1,6‐Enynes

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(6), P. 1220 - 1268

Published: Jan. 22, 2024

Abstract Elaborated molecular architectures, specifically those bearing one or more carbon stereocenters, stand as an important class of carbocyclic and heterocyclic frameworks because they are frequently occurring core structures in numerous natural products biologically active pharmaceutical molecules. Over the past few decades, development versatile synthetic approaches via cascade cyclization reactions 1,6‐enynes for construction a series fused spiro compounds has been focus great deal research initiatives. These synthesis strategies peculiarly fascinating context assembly wide array molecules, products, agrochemicals, functional materials. In this review, recent developments transformations with diverse coupling reagents summarized since 2018, which could be divided into five categories: 1) Introduction; 2) Transition metal catalyzed 1,6‐enynes; 3) Metal‐free 4) Visible‐light‐induced 5) Electrocatalytic 1,6‐enynes.

Language: Английский

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Copper Catalyst-Promoted Regioselective Multicomponent Cascade Cyclization of 3-Aza-1,5-enynes with Sulfur Dioxide and Cycloketone Oxime Esters to Access Cyanoalkylsulfonylated 1,2-Dihydropyridines

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(3), P. 1515 - 1523

Published: Jan. 22, 2024

Radical cascade cyclization via the cracking of alkenyl C–H has emerged as an attractive and remarkable tool for rapid construction ring frameworks with endocyclic double bonds. We developed a reaction 3-aza-1,5-enynes sulfur dioxide cycloketone oxime esters to access cyanoalkylsulfonylated 1,2-dihydropyridines, which can be easily converted pyridine derivatives. This protocol involves radical addition C≡C bond 6-endo features high regioselectivity broad substrate scope.

Language: Английский

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Visible-Light-Mediated Three-Component Radical Iodosulfonylative Cyclization of Enynes

Organic Letters, Journal Year: 2022, Volume and Issue: 24(13), P. 2515 - 2519

Published: March 30, 2022

An efficient three-component radical iodosulfonylative cyclization of enynes is described. The visible-light irradiation iodoform with sulfinates enables sulfonyl generation under catalyst- and oxidant-free conditions triggers the addition, iodination cascade reactions, giving various vinyl iodide containing sulfones in moderate to good yields.

Language: Английский

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Construction of sulfonated spiro[5,5]trienones from sulfur dioxide via iron-catalyzed dearomative spirocyclization of biaryls

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(7), P. 1937 - 1942

Published: Jan. 1, 2022

An iron-catalyzed dearomative spirocyclization of biaryl ynones with sodium metabisulfite and cycloketone oxime esters is developed for the construction sulfonated spiro[5,5]trienones.

Language: Английский

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Base-catalyzed stereoselective thiosulfonylation of ynones for the facile synthesis of thio-functionalized vinyl sulfones

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(5), P. 1224 - 1229

Published: Jan. 1, 2023

Brønsted base catalyzed thiosulfonylation and trifluoromethylthiosulfonylation of ynones produced thio-functionalized vinyl sulfones in high yields with excellent E -selectivity.

Language: Английский

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Iron(II)‐Catalyzed Cyanoalkylsulfonylation/Annulation Cascades toward Functionalized Sulfonylated Pyrrolidone Alkylnitriles

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(8), P. 1179 - 1184

Published: April 1, 2023

Abstract Under heating conditions, an iron(II)‐catalyzed cascade cyanoalkylsulfonylation/cyclization reaction is developed to produce cyanoalkylsulfonylated pyrrolidones bearing with a free CN moiety. This alkyl radical disconnection and annulation protocol enjoys chemo‐ regioselectivity the tolerance toward range of functional groups. The reactive cyanoalkyl radical, which was originated from ring‐opening cyclic imine found be capable capturing in‐situ generated “SO 2 ” species DABSO, thus leading production sulfonyl subsequent alkene sequences. magnified image

Language: Английский

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Photoinduced Alkylsulfonylation and Cyanoalkylsulfonylation of Morita–Baylis–Hillman Adducts via Multicomponent Insertion of Sulfur Dioxide

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(7), P. 4877 - 4887

Published: March 8, 2024

General and convenient visible-light-promoted alkylsulfonylation cyanoalkylsulfonylation of MBH adducts have been developed through the multicomponent insertion sulfur dioxide, enabling assembly two C–S bonds to generate structurally diverse allylic alkylsulfones (43 examples in total). The reaction with potassium alkyltrifluoroborates 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) adduct afforded sulfones generally good yields. Notably, addition N,N,N′,N′-tetramethylethylenediamine as a base into photocatalytic system led yielding an alkyl sulfonyl unit cyano group-anchored trisubstituted alkenes by utilizing cycloketone oxime esters C-radical precursors. Both these reactions constructed bonds, all desired products were obtained moderate excellent yields complete stereospecificity.

Language: Английский

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Synthesis of β-cyanoalkylsulfonylated vinyl selenides through a four-component reaction

Chemical Communications, Journal Year: 2021, Volume and Issue: 57(94), P. 12603 - 12606

Published: Jan. 1, 2021

A mild copper-catalyzed four-component selenosulfonylation of alkynes, cycloketone oxime esters, DABCO (SO2)2 and diselenides has been developed. This method enables the rapid assembly β-cyanoalkylsulfonylated vinyl selenides in moderate to good yields. Advantages this protocol include a broad substrate scope, functional group tolerance late-stage functionalization complex molecules. Moreover, potential utility methodology is demonstrated through simple oxidation products access synthetically important alkynyl sulfones. Mechanistic studies suggest that cyanoalkylsulfonyl radical intermediate involved process.

Language: Английский

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