137124-37-9

Upstream product

• 137124-26-6 2-Pentafluorophenylamino-3-phenyl-cycloprop-2-enone 
• 771-60-8 2,3,4,5,6-pentafluoroaniline 
• 103-80-0 phenylacetyl chloride 
• 1423-15-0 perfluorophenyl azide 
• 122-78-1 phenylacetaldehyde 

Relevant academic research and scientific papers

Base-catalyzed synthesis of aryl amides from aryl azides and aldehydes

Aryl amides have been used as important compounds in pharmaceuticals, materials and in molecular catalysis. The methods reported to prepare aryl amides generally require very specific reagents, and the most popular carboxyl-amine coupling reactions demand stoichiometric activators. Herein, we report that aryl azides react with aldehydes under base-catalyzed conditions to yield aryl amides efficiently. Mechanistic investigations support the formation of triazoline intermediates via azide-enolate cycloaddition, which subsequently undergo rearrangement to give amides by either thermal decomposition (20-140 °C) or aqueous acid work-up at room temperature. The strategy does not require nucleophilic anilines and is especially efficient for highly electron-deficient aryl amides, including perfluoroaryl amides, which are otherwise challenging to synthesize.

N, N -diethylurea-catalyzed amidation between electron-deficient aryl azides and phenylacetaldehydes

Urea structures, of which N,N-diethylurea (DEU) proved to be the most efficient, were discovered to catalyze amidation reactions between electron-deficient aryl azides and phenylacetaldehydes. Experimental data support 1,3-dipolar cycloaddition between DEU-activated enols and electrophilic phenyl azides, especially perfluoroaryl azides, followed by rearrangement of the triazoline intermediate. The activation of the aldehyde under near-neutral conditions was of special importance in inhibiting dehydration/aromatization of the triazoline intermediate, thus promoting the rearrangement to form aryl amides.

Selective radical amination of aldehydic C(sp2)-H bonds with fluoroaryl azides via Co(ii)-based metalloradical catalysis: Synthesis of N-fluoroaryl amides from aldehydes under neutral and nonoxidative conditions

The Co(ii) complex of the D2h-symmetric amidoporphyrin 3,5-DitBu-IbuPhyrin, [Co(P1)], has proven to be an effective metalloradical catalyst for intermolecular amination of C(sp2)-H bonds of aldehydes with fluoroaryl azides. The [Co(P1)]-catalyzed process can employ aldehydes as the limiting reagents and operate under neutral and nonoxidative conditions, generating nitrogen gas as the only byproduct. The metalloradical aldehydic C-H amination is suitable for different combinations of aldehydes and fluoroaryl azides, producing the corresponding N-fluoroaryl amides in good to excellent yields. A series of mechanistic studies support a stepwise radical mechanism for the Co(ii)-catalyzed intermolecular C-H amination. This journal is the Partner Organisations 2014.

Flash Photolytic Decarbonylation and Ring-Opening of 2-(N-(Pentafluorophenyl)amino)-3-phenylcyclopropenone. Isomerization of the Resulting Ynamine to a Ketenimine, Hydration of the Ketenimine, and Hydrolysis of the Enamine Produced by Ring-Opening

Flash photolysis of 2-(N-(pentafluorophenyl)amino)-3-phenylcyclopropenone, 4, in aqueous solution was found to produce N-(pentafluorophenyl)phenylethynamine, 3, by the expected photodecarbonylation reaction and also 2-phenyl-3-(N-(pentafluorophenyl)amino)acrylic acid, 5, by an apparently unprecedented photochemical ring-opening process. The ynamine underwent rapid isomerization to N-(pentafluorophenyl)phenylketenimine, 9, by an acid-catalyzed route that involves rate- determining proton transfer to the β-carbon atom of the ynamine and also by a base-catalyzed route involving equilibrium ionization of the N-H bond of the ynamine to give an ynamide ion followed by rate-determining β-carbon protonation of this ion. Saturation of the base catalysis allowed determination of the acidity constant of the ynamine; the result, pQa = 10.23, makes this amine a remarkably strong nitrogen acid. Hydration of the ketenimine 9 gave N-(pentafluorophenyl)phenylacetamide, 6, as the ultimate product produced by this reaction route, and hydrolysis of the aminoacrylic acid 5 gave pentafluoroaniline, 7, and 2-phenylformylacetic acid, 10, which underwent decarboxylation to phenylacetaldehyde, 8, as the ultimate products of this route.

Flash photolytic generation of primary, secondary, and tertiary ynamines in aqueous solution and study of their carbon-protonation reactions in that medium

A group of nine phenylynamines (PhC≡CNH2, PhC≡CNHCH(CH3)2, PhC≡CNHC6H11, PhC≡CNHC6H5, PhC≡CNHC6F5, PhC≡CN(CH2)5, PhC≡CN(CH2CH2)2O, PhC≡CN(CH2CH2CN)2, and PhC≡CN(CH3)C6F5) were generated in aqueous solution by flash photolytic decarbonylation of the corresponding phenylaminocyclopropenones, and the kinetics of their facile decay in that medium were studied. This decay is catalyzed by acids for all ynamines-primary, secondary, and tertiary-and also by bases for primary and secondary ynamines. Solvent isotope effects and the form of acid-base catalysis show that the acid-catalyzed path involves formation of keteniminium ions by rate-determining proton transfer to the β-carbon atoms of the ynamines. The ions generated from primary and secondary ynamines then lose nitrogen-bound protons to give ketenimines, and the ketenimines obtained from secondary ynamines are hydrated to phenylacetamides, whereas that from the primary ynamine tautomerizes to phenylacetonitrile. Keteniminium ions formed from tertiary ynamines have no nitrogen-bound protons that can be lost, and they are therefore captured by water instead, and the amide enols thus produced then ketonize to phenylacetamides. The base-catalyzed decay of primary and secondary ynamines also generates ketenimines, but protonation on the β-carbon is now preceeded by proton removal from nitrogen. Rate constants for β-carbon protonation of PhC≡CNHCH(CH3)2 and PhC≡CN(CH2)5 by a series of carboxylic acids give linear Bronsted relations with exponents α = 0.29 and 0.28, respectively, whereas inclusion of literature data for protonation of PhC≡CN-(CH2)5 by a group of weaker acids gives a curved Bronsted relation whose exponent varies from 0.25 to 0.97. Application of Marcus rate theory to this curved Bronsted relation produces the intrinsic barrier ΔG((+))(o) = 3.26 ± 0.19 kcal mol-1 and the work term w(r) = 8.11 ± 0.15 kcal mol-1.