68614-52-8

Upstream product

• 119-53-9 2-hydroxy-2-phenylacetophenone 
• 959-33-1 3-(4-methoxyphenyl)-1-phenylprop-2-en-1-one 
• 4070-75-1 1,4-diphenyl-but-2-ene-1,4-dione 
• 100-66-3 methoxybenzene 
• 5908-41-8 benzoyltrimethylsilane 
• 22252-15-9 trans-4-methoxychalcone 
• 611-73-4 Benzoylformic acid 
• 637-69-4 4-Methoxystyrene 
• 17292-57-8 1-phenyl-1,2-propanedione-2-O-benzoyl oxime 
• 100-52-7 benzaldehyde 
• 101018-39-7 α-ethenyl-α-phenyl-4-methoxybenzenemethanol 

Downstream Products

• 70487-19-3 3-(4-methoxyphenyl)-2,5-diphenyl-1H-pyrrole 

Relevant academic research and scientific papers

N-Heterocyclic Carbene-Photocatalyzed Tricomponent Regioselective 1,2-Diacylation of Alkenes Illuminates the Mechanistic Details of the Electron Donor-Acceptor Complex-Mediated Radical Relay Processes

Progress in the development of photocatalytic reactions requires a detailed understanding of the mechanisms underpinning the observed reactivity, yet mechanistic details of many photocatalytic systems, especially those that involve electron donor-acceptor complexes, have remained elusive. We report herein the development and a combined mechanistic and computational study of photocatalytic alkene 1,2-diacylation that enables a regioselective installation of two different acyl groups, establishing direct, tricomponent access to 1,4-diketones, key intermediates in heterocyclic and medicinal chemistry. The studies revealed the central role of the electron donor-acceptor complex formed from an N-heterocyclic carbene (NHC) catalyst-derived intermediate and an acyl transfer reagent, providing a detailed description of the structural and electronic factors determining the characteristics of the photoinduced charge-transfer process that mediates photocatalytic transformation. The in-depth investigation also illuminated the roles of other radical intermediates and electron donors relevant to the catalytic activities of N-heterocyclic carbenes in radical reactions.

Visible-Light-Promoted Photocatalyst-Free Hydroacylation and Diacylation of Alkenes Tuned by NiCl2·DME

Herein, we describe a visible light-promoted hydroacylation strategy that facilitates the preparation of ketones from alkenes and 4-acyl-1,4-dihydropyridines via an acyl radical addition and hydrogen atom transfer pathway under photocatalyst-free conditions. The efficiency was highlighted by wide substrate scope, good to high yields, successful scale-up experiments, and expedient preparation of highly functionalized ketone derivatives. In addition, this protocol allows for the synthesis of 1,4-dicarbonyl compounds through alkene diacylation in the presence of NiCl2·DME.

Acyl radicals from α-keto acids using a carbonyl photocatalyst: Photoredox-catalyzed synthesis of ketones

Acyl radicals have been generated from α-keto acids using inexpensive and commercially available 2-chloro-thioxanthen-9-one as the photoredox catalyst under visible light illumination. These reactive species added to olefins or coupled with aryl halides via a bipyridylstabilized Ni(II) catalyst, enabling easy access to a diverse range of ketones. This reliable, atom-economical, and eco-friendly protocol is compatible with a wide range of functional groups.

UV light-mediated difunctionalization of alkenes through aroyl radical addition/1,4-/1,2-Aryl shift cascade reactions

UV light-mediated difunctionalization of alkenes through an aroyl radical addition/1,4-/1,2-aryl shift has been described. The resulted aroyl radical from a photocleavage reaction added to acrylamide compounds followed by cyclization led to the formation of oxindoles, whereas the addition to cinnamic amides aroused a unique 1,4-aryl shift reaction. Furthermore, the difunctionalization of alkenes of prop-2-en-1-ols was also achieved through aroyl radical addition and a sequential 1,2-aryl shift cascade reaction.

Thiazolium-catalyzed additions of acylsilanes: A general strategy for acyl anion addition reactions

A strategy utilizing N-heterocyclic carbenes (NHCs) derived from thiazolium salts has been developed for the generation of carbonyl anions from acylsilanes. Synthetically useful 1,4-diketones and N-phosphinoyl-α- aminoketones have been prepared in good to excellent yields via NHC-catalyzed additions of acylsilanes to the corresponding α,β-unsaturated systems and N-phosphinoylimines. These organocatalytic reactions are air- and water-tolerant methods to execute robust carbonyl anion addition reactions. Additionally, polysubstituted aromatic furans and pyrroles have been efficiently synthesized in a one-pot process using this carbonyl anion methodology. The addition of alcohols to the reaction renders the process catalytic in thiazolium salt. In an effort to synthesize a potential intermediate along the proposed reaction pathway, silylated thiazolium carbinols have been identified to provide good yields of carbonyl anion addition products when subjected to the standard reaction conditions in the presence of suitable electrophiles.

The Thiazolium-Catalyzed Sila-Stetter Reaction: Conjugate Addition of Acylsilanes to Unsaturated Esters and Ketones

A new acyl anion addition reaction between acylsilanes and α,β-unsaturated conjugate acceptors promoted by a nucleophilic organic catalyst has been disclosed. The 1,4-dicarbonyl products produced in this reaction are highly useful synthons. Neutral carbenes (or zwitterions) generated in situ from commercial thiazolium salts are used as effective catalysts for the reaction which is in contrast to established anionic catalysts typically employed to promote the required Brook rearrangement (1,2-silyl shift from carbon to oxygen) involved in the reported reaction. This process successfully utilizes acylsilanes as tunable acyl anion progenitors and is tolerant of a wide range of structural diversity on the acylsilane or the conjugate acceptor. Copyright

The Diverse Carbenic and Cationic Chemistry of 3-Diazo-2,5-diphenylpyrrole

3-Diazo-2,5-diphenylpyrrole (1) thermolyzes and photolyzes to 2,5-diphenyl-3H-pyrrolylidene (3), which inserts into methylene hydrogen of cyclohexane and methyne hydrogen of cumene.Hydrogen abstraction to give 2,5-diphenylpyrrole (7) occurs competitively in these systems.Carbene 3 reacts with cyclohexene, allylbenzene, and 2,3-dimethyl-2-butene to give 3-(allylically substituted)-2,5-diphenylpyrroles (15, 20, 21, and 29) as the only products of olefin incorporation along with 7.The initial position of the double bond in the olefin may be altered in the overall insertion process, and cyclopropanes are not isolable.The apparent behavior of 3 with saturated and olefinic hydrocarbons is as singlet 8s and triplet 9t.Reactions of 3 with anisole (31a) and with toluene (31b), benzenes substituted by electron-donor groups, result in selective ortho and/or para substitution to give 2,5-diphenyl-3-(substituted-phenyl)pyrroles (38a, 35, and 38b) and in hydrogen abstraction to 7.Insertion into the methyl groups and hydrogen abstraction also occur in reactions of 3 with 31b, yielding 3-benzyl-2,5-diphenylpyrrole (39) and 1,2-diphenylethane (40).Benzene (42a), however, reacts thermally or photolytically with 1 to form 1,3-diphenyl-2H-cyclooctapyrrole (46a), a member of a new heterocyclic system.Ring expansions to 4-, 5-, and 6-cyano-1,3-diphenyl-2H-cyclooctapyrroles (46b, 46b', and 46b'') and 4-, 5-, and 6-nitro-1,3-diphenyl-2H-cyclooctapyrroles (46c, 46c', and 46c'') are the principal reactions of 3 with benzonitrile (42b) and nitrobenzene (42c). 3-(m-Nitrophenyl)-2,5-diphenylpyrrole (47b) is also formed from 1 and 42c at 170 deg C.Thermolysis and photolysis of 1 to effect substitution and ringexpansion of benzenes may involve electrophilic attack of 8s to form spiropyrrolonorcaradienes (32).Directed heterolytic ring opening of 32 and (1,5 sigmatropic) rearrangements of hydrogen will rationalize the selective ortho and/or para substitution processes.Cyclooctapyrroles may arise from (electrocyclic) isomerization of 32 to spirocycloheptatrienes 44, (1,5 sigmatropic) rearrangement involving ring expansion to 45, and then hydrogen migration.Triplet photosensitization of 1 in 42a and 42b leads to 2,3,5-triphenylpyrrole (47a) and 3-(o-cyanophenyl)-2,5-diphenylpyrrole (47c), products of aromatic substitution rather than ring expansion.Such photolytic processes may involve generation and then addition of 9t to 42a and 42b, spin inversion of the triplet to singlet diradical intermediates, and successive hydrogen migrations.Aniline (59a), N-methylaniline (59b), and N,N-dimethylaniline are nucleophiles in that they are pyrrylated on nitrogen by 1 at 180 deg C.Primary and secondary alcohols and 1 undergo oxidation/reduction to carbonyls and 7; conversion to 3-alkoxy-2,5-diphenylpyrroles is minor except in the presence of ...