RESUMEN
The synthesis of tertiary phosphines(III) has been a long-standing challenge in synthetic chemistry because of inevitable issues including harsh conditions, sensitive organometallic reagents, and prefunctionalized substrates in traditional synthesis. Herein, we report a strategically novel C(sp3)-H bond phosphorylation that enables the assembly of structurally diverse tertiary phosphines(III) from industrial phosphine(III) sources under mild photocatalytic conditions. The merger of ligand-to-metal charge transfer (LMCT) of FeCl3 with the hydrogen atom-transfer (HAT) process is the key for the generation of alkyl radicals from hydrocarbons. Strikingly, this catalytic system can be successfully applied for the polymerization of electron-deficient alkenes.
RESUMEN
An unprecedented DMAP-catalysed amidation of aryl and alkyl carboxylic acids with organo-cyanamides has been developed. Unlike the use of N-cyano-N-phenyl-p-methylbenzenesulfonamide (NCTS) as an electrophilic cyanating reagent, an unusual desulfonylation/decyanation reaction model has been disclosed for the first time. Remarkable features of this reaction include readily available substrates, simple operation and broad scope, enabling the efficient synthesis of structurally diverse amides. The synthetic utility of this protocol was demonstrated by the late-stage amidation of bioactive carboxylic acids and a scale-up reaction.
Asunto(s)
Ácidos Carboxílicos , Cianamida , Indicadores y Reactivos , Estructura Molecular , AmidasRESUMEN
An unprecedented I2/FeCl3-promoted cascade reaction of aryl methyl ketones with 8-aminoquinolines for the convenient synthesis of (E)-3-(2-acyl-1H-benzo[d]imidazol-4-yl)acrylaldehydes was developed by merging annulation with ring deconstruction. This novel strategy unlocked the new reactivity of 8-aminoquinolines and provided an attractive platform for the ring opening of unactivated N-heteroaromatic compounds. Preliminary mechanistic investigation suggested that dual C(sp3)-H amination/C-N bond cleavage were key reaction steps. Furthermore, late-stage modification of the obtained products successfully delivered pyrazole and isoxazole derivatives, increasing the practicability and application potential of this methodology in organic synthesis.
RESUMEN
A practical copper-catalyzed multicomponent reaction has been developed for the synthesis of 1 H-[1,2,3]triazolo[4,5- c]quinoline derivatives from commercially available 2-bromobenzaldehydes, aryl methyl ketones, and sodium azide. This protocol integrated consecutive base-promoted condensation, [3 + 2] cycloaddition, copper-catalyzed SNAr, and denitrogenation cyclization sequences. Preliminary mechanistic studies revealed that CuBr2 acted as a multifunctional catalyst to streamline this domino process. The mild catalytic system enabled effective construction of one C-C and four C-N bonds in one operation.
RESUMEN
An efficient transition-metal-free oxidative cyclization reaction using isatins and alkynes for the facile synthesis of structurally diverse 4-quinolones has been developed. Intriguingly, switchable access to substituted 3-carboxylate-4-quinolones and 1-vinyl-3-carboxylate-4-quinolones could be achieved by choosing a different base in the reaction. The obtained products could undergo further transformations, increasing the application potential of the method in organic synthesis.
RESUMEN
A copper-catalyzed cascade reaction using isatins and amidine hydrochlorides for the synthesis of 2-(1,3,5-triazin-2-yl)aniline derivatives has been developed. This reaction features commercially available starting materials, mild reaction conditions and good functional group tolerance.
RESUMEN
An efficient transition-metal-free cascade reaction has been developed for the facile synthesis of 12H-benzo[4,5]thiazolo[2,3-b]quinazolin-12-one derivatives from commercially available isatins and 2-haloaryl isothiocyanates. A preliminary mechanistic study suggested an interrupted Dimroth rearrangement was the key step for the successful transformation.
RESUMEN
An unusual benzannulation reaction has been realized by integrating intermolecular adol condensation with subsequent intramolercular base-promoted homolytic aromatic substitution. This novel cascade reaction provides a straightforward approach toward various naphtho-fused oxindoles from 2-halobenzaldehydes and indolin-2-ones in the presence of Cs2CO3 in DMSO. The enolates of indolin-2-ones as new and internal electron donors have been demonstrated to initiate intramolecular radical dehalogenative coupling.
RESUMEN
A synergetic tert-butyl hydroperoxide/K3PO4-promoted oxidative cyclization has been developed for the facile synthesis of various functionalized quinazolin-4(3H)-ones from commercially available isatins and amidine hydrochlorides at room temperature. The synthetic utility of this strategy was illustrated by the convenient synthesis of tryptanthrin derivatives via a self-dimerization of isatins under the same conditions.
RESUMEN
An efficient three-component domino reaction of 2-bromoaldehydes, benzylamines, and sodium azide has been developed for the synthesis of quinazoline derivatives. This domino process involves copper-catalyzed SNAr, oxidation/cyclization, and denitrogenation sequences. The mild catalytic system enabled the effective construction of three C-N bonds in one operation.
RESUMEN
A highly efficient Fe/Cu relay-catalyzed domino protocol has been developed for the synthesis of 2-phenylquinazolin-4-amines from commercially available ortho-halogenated benzonitriles, aldehydes, and sodium azide. This elegant domino process involved consecutive iron-mediated [3 + 2] cycloaddition, copper-catalyzed SNAr, reduction, cyclization, oxidation, and copper-catalyzed denitrogenation sequences. The formed structure is the privileged core in drugs and bioactive molecules.
RESUMEN
A highly efficient multicomponent domino protocol has been developed for the synthesis of 5-phenyl-[1,2,3]triazolo[1,5-c]quinazolines from simple and readily available (E)-1-bromo-2-(2-nitrovinyl)benzenes, aldehydes, and sodium azide. This elegant domino process involved consecutive [3 + 2] cycloaddition, copper-catalyzed S(N)Ar, reduction, cyclization, and oxidation sequences. Notably, sodium azide acted as a dual nitrogen source in the construction of this novel fused N-heterocycle.
Asunto(s)
Azidas/química , Cobre/química , Compuestos Heterocíclicos/síntesis química , Quinazolinas/síntesis química , Reacción de Cicloadición , Compuestos Heterocíclicos/química , Estructura Molecular , Oxidación-Reducción , Quinazolinas/químicaRESUMEN
A copper-catalyzed domino protocol for the synthesis of 2-(1,3,4-oxadiazol-2-yl)aniline derivatives has been developed from simple and available isatins and hydrazides. This domino process integrated consecutive condensation, base-promoted ring-opening and the key copper-catalyzed decarboxylative coupling for intramolecular C-O bond formation.
RESUMEN
A highly efficient three-component domino protocol has been developed for the synthesis of [1,2,4]triazolo[1,5-b]isoquinolin-5(1H)-ones from simple and readily available o-halogenated benzohydrazides, aldehydes and nitriles. This domino process involves sequential selective condensation, copper-catalyzed intermolecular C-arylation and bicyclization. Notably, the use of ligands and anaerobic conditions can be avoided in this reaction.
Asunto(s)
Cobre/química , Isoquinolinas/síntesis química , Triazoles/síntesis química , Aldehídos/química , Derivados del Benceno/química , Catálisis , Halogenación , Isoquinolinas/química , Nitrilos/química , Triazoles/químicaRESUMEN
Multi-birds with one stone: A cascade coupling strategy was developed for the synthesis of ß-carbolines. The method can direct the synthesis of ß-carboline and isoquinoline-containing natural products with high yields. Moreover, this protocol can also be further applied towards the total synthesis of natural products fascaplysin and papaverin (see scheme).
Asunto(s)
Productos Biológicos/síntesis química , Carbolinas/síntesis química , Isoquinolinas/síntesis química , Productos Biológicos/química , Carbolinas/química , Indoles/síntesis química , Indoles/química , Isoquinolinas/química , Estructura Molecular , Papaverina/síntesis química , Papaverina/químicaRESUMEN
An efficient one-pot synthetic protocol has been proposed for the synthesis of luntonin F from easily available starting materials. Through a rational logical design, multifundamental reactions (iodination, Kornblum oxidation, and annulation) were assembled in one-pot. The developed approach can efficiently synthesize luntonin F and a diversity of analogues.
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Alcaloides/síntesis química , Productos Biológicos/síntesis química , Quinazolinas/síntesis química , Alcaloides/química , Productos Biológicos/química , Técnicas Químicas Combinatorias , Estructura Molecular , Oxidación-Reducción , Peganum/química , Quinazolinas/químicaRESUMEN
An I(2)-CF(3)SO(3)H synergistic promoted sp(3) C-H bond diarylation protocol was developed for the synthesis of 2,2-bis(4-(dimethylamino)phenyl)-1-aryl ethanones. The reaction performed well in the absence of any metal and ligand. It integrated three reactions with different mechanisms (iodination, Kornblum oxidation, and hydroarylation) in a single reactor.
Asunto(s)
Yodo/química , Cetonas/química , Mesilatos/química , Ligandos , Modelos Moleculares , Estructura MolecularRESUMEN
An I(2) promoted domino protocol was developed to construct 2-acylbenzothiazoles from simple and readily available aromatic ketones/unsaturated methyl ketones and o-aminobenzenethiols. The reaction proceeded smoothly under metal-free and peroxide-free conditions.
Asunto(s)
Benzotiazoles/química , Benzotiazoles/síntesis química , Carbono/química , Hidrógeno/química , Yodo/química , Catálisis , Técnicas de Química Sintética , Ciclización , Oxidación-ReducciónRESUMEN
A multipathway coupled domino strategy has been developed for the efficient synthesis of 2-acylbenzothiazoles from multiform substrates arylethenes, arylacetylenes, 2-hydroxy-aromatic ketones, and carbinols via four distinct pathways. Through a logical coupled oxidation/heterocyclization domino process, a variety of 2-acylbenzothiazoles were synthesized free of metal in one pot.
Asunto(s)
Benzotiazoles/síntesis química , Alcoholes/química , Alquenos/química , Alquinos/química , Benzotiazoles/química , Catálisis , Técnicas Químicas Combinatorias , Ciclización , Cetonas/síntesis química , Cetonas/química , Estructura Molecular , Oxidación-ReducciónRESUMEN
A molecular I(2)-promoted sp(3) C-H bond dual-(het)arylation protocol was developed for the synthesis of 2,2-bisindolyl-1-arylethanones. Through a logical design, three mechanism-different reactions (iodination, Kornblum oxidation, and Friedel-Crafts reaction) were assembled in a single reactor. A variety of 2,2-bisindolyl-1-aryl ethanones were synthesized from simple and readily available aryl methyl ketones and indoles. In the reaction, metal, base, and ligand were all avoidable.