Photocatalytic Thio/Selenosulfonylation–Bicyclization of Indole-Tethered 1,6-Enynes Leading to Substituted Benzo[c]pyrrolo[1,2,3-lm]carbazoles

Organic Letters, Год журнала: 2024, Номер 26(18), С. 3828 - 3833

Опубликована: Апрель 29, 2024

The photocatalyzed radical-triggered thio/selenosulfonylation–bicyclization of indole-tethered 1,6-enynes has been established for the first time, enabling synthesis various previously unreported thio/selenosulfonylated benzo[c]pyrrolo[1,2,3-lm]carbazoles with moderate to good yields under mild conditions. reaction pathway was proposed, consisting energy transfer, homolytic cleavage, radical addition, 5-exo-dig, coupling, and a Mallory cascade. This approach exhibits wide substrate compatibility excellent tolerability toward functional groups is characterized by its remarkable efficiency in both bond formation annulation.

Язык: Английский

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Electrocatalytic Annulation–Iodosulfonylation of Indole‐Tethered 1,6‐Enynes to Access Pyrrolo[1,2‐a]indoles

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(10)

Опубликована: Янв. 9, 2024

Abstract We present the first example of electrocatalytic three‐component annulation–iodosulfonylation indole‐tethered 1,6‐enynes with arylsulfonyl hydrazides and KI for accessing various iodosulfonated pyrrolo[1,2‐ a ]indoles in moderate to excellent yields high stereospecificity. This electrosynthesis opens new avenues construction skeleton good functional group compatibility under environmentally benign condition. Based on control experiments cyclic voltammetry data, we suggested plausible reaction mechanism which included anodic oxidation, homolysis iodide, radical addition, 5 ‐ exo dig cyclization, coupling or nucleophilic attack iodide ions cascade.

Язык: Английский

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Stereospecific Assembly of Trisubstituted Alkenes via Photoinduced Nitrogen‐Centered Radical‐Triggered C—C Bond Cleavage/Functionalization of Oxime Esters

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(12), С. 1399 - 1406

Опубликована: Фев. 29, 2024

Comprehensive Summary A general and convenient photoredox‐catalyzed acylation alkylcyanation of MBH acetates has been established, enabling the assembly C(sp 2 )–C(sp 3 ) bond by a nitrogen‐centered radical strategy for synthesis trisubstituted alkenes in moderate to excellent chemical yields (48 examples total). The reaction with acyl (indanone) oxime esters afforded containing 1,4‐dicarbonyl groups. Interestingly, use Eosin Y as photocatalyst catalytic system resulted formation distal cyano group‐anchored via deconstructive functionalization cycloketone esters. Notably, these resulting compounds could be applied late‐stage transformations, providing important methods dihydropyridazin‐3(2 H )‐one.

Язык: Английский

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Enantioselective Amino- and Oxycyanation of Alkenes via Organic Photoredox and Copper Catalysis

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(33), С. 18247 - 18252

Опубликована: Авг. 14, 2023

The β-amino nitrile moiety and its derivatives frequently appear in natural product synthesis, drug design, as ligands asymmetric catalysis. Herein, we describe a direct route to these complex motifs through the amino- oxycyanation of olefins utilizing an acridinium photooxidant conjunction with copper transformation can be rendered by using serine-derived bisoxazoline ligand. Mechanistic studies implicate olefin-first oxidation. scope amines for aminocyanation reaction has been greatly expanded undergoing cation radical intermediate opposed previous N-centered radical-initiated aminocyanations. Furthermore, alkyl carboxylic acids were included nucleophiles this type first time without any decarboxylative side reactions.

Язык: 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, Год журнала: 2024, Номер 89(7), С. 4877 - 4887

Опубликована: Март 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.

Язык: Английский

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Catalytic Radical-Triggered Annulation/Iododifluoromethylation of Enynones for the Stereospecific Synthesis of 1-Indenones

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(13), С. 8532 - 8541

Опубликована: Май 23, 2023

A new Pd(II)-catalyzed annulation/iododifluoromethylation of enynones has been developed for the synthesis versatile 1-indanones with moderate to good yields (26 examples). The present strategy enabled concomitant incorporation two important difluoroalkyl and iodo functionalities into 1-indenone skeletons (E)-stereoselectivity. mechanistic pathway was proposed, consisting radical-triggered α,β-conjugated addition/5-exo-dig cyclization/metal radical cross-coupling/reductive elimination cascade.

Язык: Английский

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Photocatalytic Multicomponent Annulation of Amide-Anchored 1,7-Diynes Enabled by Deconstruction of Bromotrichloromethane

Molecules, Год журнала: 2024, Номер 29(4), С. 782 - 782

Опубликована: Фев. 8, 2024

We present the first example of visible-light-mediated multicomponent annulation 1,7-diynes by taking advantage quadruple cleavage olf carbon-halogen bonds BrCCl3 to generate a C1 synthon, which was adeptly applied preparation skeletally diverse 3-benzoyl-quinolin-2(1H)-one acetates in moderate good yields. Controlled experiments demonstrated that H2O acted as both oxygen and hydrogen sources, gem-dichlorovinyl carbonyl compound exhibited critical intermediate this process. The mechanistic pathway involves Kharasch-type addition/6-exo-dig cyclization/1,5-(SN”)-substitution/elimination/binucleophilic 1,6-addition/proton transfer/tautomerization sequence.

Язык: Английский

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Copper‐catalyzed radical‐induced annulation‐halo(bi)cyanomethylation of indole‐tethered 1,6‐enynes toward pyrrolo[1,2‐a]indoles

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер 366(17), С. 3578 - 3584

Опубликована: Июнь 18, 2024

Abstract A copper‐catalyzed radical‐induced annulation‐halocyanomethylation of indole‐linked 1,6‐enynes has been established using haloacetonitrile as radical precursors, enabling the synthesis 21 cyanomethylated pyrrolo[1,2‐ a ]indoles with yields ranging from 42% to 81% and Z / E ratio up 19:1. Moreover, by adjusting reaction temperature, variation annulation‐bromobicyanomethylation process was achieved, resulting in production 12 bicyanomethylated ]indole isomers 41–68%. The stereoisomeric mixture products could be purified their pure configurations through recrystallization. proposed mechanism formulated series control experiments.

Язык: Английский

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Photocatalyzed Annulation‐Biselenylation of Enynone with Diarylselenides toward Biselenium‐Substituted 1‐Indanones under Metal‐ and Photosensitizer‐Free Conditions

Chinese Journal of Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Апрель 17, 2025

Comprehensive Summary A practical photocatalytic annulation‐biselenylation strategy has been developed for the efficient synthesis of biselenium‐substituted 1‐indanones (38 examples in total) with generally good yields (up to 95%) and excellent stereoselectivity (>19 : 1 Z / E ratio) by employing enynones diaryl selenides as starting materials under photosensitizer‐free conditions. The reaction mechanism involves a cascade process comprising homolytic cleavage, radical addition, 5‐ exo ‐ dig cyclization, capture, enabling sequential formation multiple bonds, such C(sp 3 )‐Se, )‐C(sp 2 ), )‐Se rapidly construct molecular complexity. Notably, this approach demonstrates wide substrate compatibility tolerability towards various functional groups. It is further characterized its remarkable efficiency creating chemical bonds achieving high atomic utilization 100%.

Язык: Английский

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Photocatalytic Site‐Selective Cascade Radical Addition of Biaryl Ynones for the Construction of Spiro‐ and Fused Carbon Rings

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(14), С. 1599 - 1605

Опубликована: Март 13, 2024

Comprehensive Summary Functionalized free radical addition/cyclization reactions represent an efficient way for introducing new functionality or coupling fragments to molecules. Ynones are good regional selectivity acceptors in organic synthesis, and many of bio‐relevant cyclic compounds could be easily obtained by direct cyclization reaction. Here, we report a photocatalytic cascade addition biaryl ynones, the divergent synthesis privileged carbon cycles. Additionally, further transformation multi‐functional group product into variety other derivatives demonstrates synthetic value this developed method.

Язык: Английский

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