2447-95-2

An efficient synthesis of 10 N-arylbenzamides was achieved by N-benzoylation of N,N-dimethyl-(N'-phenyl)thioureas with 4-substituted benzoyl chlorides in dimethylacetamide in the presence of K2CO3. The features of this method include

An efficient iron-catalyzed synthesis of N-aryl amides from N?methoxy amides and arylboronic acids is developed. FeCl3 is used as the sole catalyst for the cross-coupling reaction between N?methoxy amides and arylboronic acids without any other

Transamidation reactions are often mediated by reactive substrates in the presence of overstoichiometric activating reagents and/or transition metal catalysts. Here we report the use of CO2as a traceless catalyst: in the presence of catalytic amounts of CO2, transamidation reactions were accelerated with primary, secondary, and tertiary amide donors. Various amine nucleophiles including amino acid derivatives were tolerated, showcasing the utility of transamidation in peptide modification and polymer degradation (e.g., Nylon-6,6). In particular,N,O-dimethylhydroxyl amides (Weinreb amides) displayed a distinct reactivity in the CO2-catalyzed transamidation versus a N2atmosphere. Comparative Hammett studies and kinetic analysis were conducted to elucidate the catalytic activation mechanism of molecular CO2, which was supported by DFT calculations. We attributed the positive effect of CO2in the transamidation reaction to the stabilization of tetrahedral intermediates by covalent binding to the electrophilic CO2

An efficient and practical methodology for the synthesis of N-arylamides has been developed via copper-catalyzed amidation of diaryliodonium salts with nitriles. Various substituted aryl nitriles and aliphatic nitriles could be applied in the reaction, providing a series of N-arylated amides in moderate to good yields. This procedure provides an alternative route for the synthesis of various N-arylamides. A proposed mechanism based on control experiments is also presented.

The invention discloses a preparation method of an N-aryl amide compound, which comprises the following steps: (1) putting diaryliodonium salt and Cu(OAc)2 into a Schlenk tube provided with a magneticstirring rod; (2) sequentially adding DCE, H2O and nitrile by using an injector, sealing the Schlenk tube, and stirring for reaction at 80 DEG C; (3) cooling the obtained solution to room temperature, and performing extraction with EtOAc; and combining organic layers, performing washing with saline water, and performing drying with anhydrous Na2SO4; and (4) removing volatile matters in vacuum, and purifying residues through column chromatography to obtain the N-aryl amide compound. Through a large number of experiments, a substrate with a simple structure is screened, the reaction conditionsare mild, the yield is high, the pollution is small, and the application prospect is wide.

The invention discloses a method for synthesizing an amide compound through photocatalysis in a water phase. The method comprises the following steps: putting catalysis amounts of a free radical initiator, an amine derivative, a carboxylic acid derivative, a phase transfer catalyst, an inorganic base and water into a reaction container, carrying out a reaction in a photocatalysis reaction instrument at certain power under a room temperature condition, after a certain time, carrying out extraction by using a small amount of ethyl acetate, and carrying out recrystallization, so as to obtain theamide compound, wherein the free radical initiator is eosin, methyl orange, sodium persulfate, ammonium persulfate or potassium peroxodisulfate, the phase transfer catalyst is tetrabutylammonium bromide, and the power of the photocatalytic reaction instrument is 5W. By adopting the method disclosed by the invention, toxic thionyl chloride or phosphorus oxychloride is not needed for a chlorinationreaction, water is adopted as a solvent, a novel photocatalysis method is used, and the amide compound with a high yield can be prepared through a room-temperature reaction for 2-5 hours with an incandescent light bulb of 5W, and in addition, the method is simple in aftertreatment, and low in cost and is an ideal green synthesis method of amide compounds.

Styrenes serve as unique aryl or arylcarboxymethylene source towards aryl isocyanides in the presence of Cu(II)/TBHP, and yield N-arylbenzamides or benzoyloxyacetanilides respectively. The chemoselectivity of the reaction is controlled by the nature of the substituents present on styrene ring. Whereas styrenes substituted with electron-releasing alkyl and alkoxy groups yield N-arylbenzamides, unsubstituted styrene and those with electron-withdrawing substituents furnish benzoyloxyacetanilides as the major product. With benzylamines as the substrate, N-arylbenzamides are formed exclusively as they act only as an aryl donor. TBHP serves as a promoter and oxygen source. Both the pathways are believed to proceed through an initial oxidative C?C bond cleavage of styrene. (Figure presented.).

The invention discloses a method for synthesizing aryl formamide with a one-pot process. The method is a one-pot synthesis method, purification of intermediate products is not required, and a reaction equation of the method is shown in the specification, wherein Ar represents phenyl, aromatic heterocycte and the like, and R represents alkyl, aryl and the like. The method for synthesizing aryl formamide has the characteristics of low reaction temperature, high safety performance, high product purity, high yield and the like, and is convenient to operate.

A novel vanadium-catalyzed one-pot domino reaction of 1,2-diketones with amidines has been identified that enables their transformation into imides and amides. The reaction proceeds by dual acylation of amidines via oxidative C(CO)-C(CO) bond cleavage of 1,2-diketones to afford N,N′-diaroyl-N-arylbenzamidine intermediates. In the reaction, these intermediates are easily hydrolyzed into imides and amides through vanadium catalysis. This method provides a practical, simple, and mild synthetic approach to access a variety of imides as well as amides in high yields. Moreover, one-step construction of imide and amide bonds with a long-chain alkyl group is an attractive feature of this protocol.

An I2/KI-promoted oxidative C-C bond formation reaction from C(sp3)-H and C(sp2)-H bonds has been used to construct quinazoline skeletons from N,N′-disubstituted amidines. The required substrates are readily prepared from the corresponding acyl chlorides, anilines, and alkyl/benzylamines by sequential amidation, chlorination, and amination reactions. Under the optimal oxidative cyclization conditions, all these amidines were conveniently transformed into the expected products in moderate to good yields. This practical and environmentally benign approach works well with crude amidine intermediates and can also be carried out on a gram scale.

A Nickel-catalyzed reductive process is described for the direct amidation of benzyl and aryl halides using carbodiimides as the amidating agent. Moreover, aryl and benzyl C–O electrophiles such as triflate, acetate, tosylate, trityl ether, and pivalate were converted into amides using this method. The in-situ-generated Ni0acts as a catalyst for the reaction at room temperature for benzylic substrates, and 70 °C for aryl electrophiles. This new nickel-catalyzed reductive coupling protocol provides a general and operationally simple method for the synthesis of diverse amides using carbodiimides. Amides bearing bulky substituents can be synthesized by this strategy in high yield, which demonstrates its effectiveness in amide synthesis.

A novel catalyst-free decarboxylative amidation of α-keto acids with amines under mild conditions has been developed. Advantages of the new protocol include avoidance of metal catalysts and high levels of functional group tolerance. In addition, the reaction can be scaled up and shows high chemoselectivity. Preliminary mechanistic studies suggest that singlet oxygen, generated from oxygen under irradiation, is the key promoter for this catalyst-free transformation.

A general and effective method for the synthesis of amides through decarboxylative amidation of α-keto acids with amines has been developed. The reaction proceeded smoothly to afford the corresponding amide products in good yield under air and shows excellent functional group tolerance. In addition, the protocol can be further applied in the synthesis of heterocyclic compounds like benzimidazoles.

The reductant zinc powder and the oxidant sodium chlorate were used together in an appropriate ratio in one pot under ambient conditions, to provide an environmentally friendly, effective, and convenient method for the synthesis of aromatic amides in good yields from nitroarenes and aldehydes in the green solvents alcohol and water under atmospheric conditions. The good results indicate that reductants and oxidants with opposing properties can not only be used together without any adverse effects, but also improve the reaction yield through their cooperation.

Photochemistry has ushered in a new era in the development of chemistry, and photoredox catalysis has become a hot topic, especially over the last five years, with the combination of visible-light photoredox catalysis and radical reactions. A novel, simple, and efficient radical oxidative decarboxylative coupling with the assistant of the photocatalyst [Ru(phen)3]Cl 2 is described. Various functional groups are well-tolerated in this reaction and thus provides a new approach to developing advanced methods for aerobic oxidative decarboxylation. The preliminary mechanistic studies revealed that: 1)an SET process between [Ru(phen)3]2+* and aniline play an important role; 2)O2 activation might be the rate-determining step; and 3)the decarboxylation step is an irreversible and fast process. Bring to light: A new approach to oxidative decarboxylation under visible light using O2 as the oxidant has been developed. A variety of functional groups were well-tolerated in this reaction and insights into the mechanism were investigated with the assistance of EPR spectroscopy, cyclic voltammetry, and theoretical studies.

Singled out: Treatment of ketones with carbodiimides in the presence of a catalytic amount of either [{HMn(CO)4}3] or [Mn 2(CO)10] gave amides in good to excellent yields. In this reaction, the carbon-carbon single bond of a ketone is cleaved efficiently. The reaction also proceeded by using isocyanates instead of carbodiimides. Copyright

Aluminum chloride, an inexpensive and commercially available Lewis acid traditionally employed for Beckmann rearrangement with stoichiometric amounts, has been now found to smoothly promote the Beckmann rearrangement of various ketoximes to the corresponding amides (up to 99% of yield) with 10mol% catalyst loading in anhydrous acetonitrile under reflux temperature.

BF3·OEt2 (Boron trifluoride etherate), an inexpensive and commercially easily available Lewis acid stoichiometrically employed for Beckamann rearrangement in general, was now found to efficiently catalyze Beckmann rearrangement of ketoximes into their corresponding amides (up to 99% yield) in anhydrous acetonitrile under reflux temperature.

Efficient methods have been developed for the direct synthesis of amides from aldehydes and a straightforward route to propiolamidines using cyclopentadienyl-free rare-earth metal amides [{(CH2SiMe 2){(2,6-iPr2C6H3)N} 2}Ln{N(SiMe3)2}(THF)] [Ln = Yb (1), Y (2), Dy (3), Sm (4), Nd (5)] as versatile catalysts, The results indicate that in the direct synthesis of amides from aldehydes the catalysts have the activity order 2>1～3～4～5. These methods have the advantage of easy preparation of the catalysts, low catalyst loading, high conversion of substrates to products, mild reaction conditions, and compatibility with a wide range of substrates.

TsCl (p-toluenesulfonyl chloride), a commercially available organosulfonyl chloride, has been widely used as a stoichiometric dehydrogenation reagent in the transformation of ketoximes into corresponding amides via the Beckmann rearrangement. It has been now found to catalyze the Beckmann rearrangement with high catalytic efficiency, converting a wide range of ketoximes into their corresponding amides under mild condition with good to excellent yields (up to 99% of yield with 1-5 mol % of catalyst loading).

Although cyclooxygenase-1 (COX-1) inhibition is thought to be a major mechanism of gastric damage by nonsteroidal anti-inflammatory drugs (NSAIDs), some COX-1-selective inhibitors exhibit strong analgesic effects without causing gastric damage. However, it is not clear whether their analgesic effects are attributable to COX-1-inhibitory activity or other bioactivities. Here, we report that N-(5-amino-2-pyridinyl)-4-(trifluoromethyl)benzamide (18f, TFAP), which has a structure clearly different from those of currently available COX-1-selective inhibitors, is a potent COX-1-selective inhibitor (COX-1 IC 50 = 0.80 ± 0.05 μM, COX-2 IC50 = 210 ± 10 μM). This compound causes little gastric damage in rats even at an oral dose of 300 mg/kg, though it has an analgesic effect at as low a dose as 10 mg/kg. Our results show that COX-1-selective inhibitors can be analgesic agents without causing gastric damage.

Microwave reactions of primary and secondary amines with imidoylbenzotriazoles 6a-w gave diversely substituted amidines 7a-Aa in 76-94% yields. Convenient preparations of a variety of amides 5a-Ab (87-96%) and imidoylbenzotriazoles 6a-w (56-95%) have also been developed using microwave irradiation under mild conditions and short reaction times. These results demonstrate further the advantages of microwave synthesis and introduce a new application of imidoylbenzotriazoles in the preparation of polysubstituted amidines.

Aromatic amides have been prepared in high to moderate yields by a new direct synthesis from aromatic carboxylic acids and aromatic amines in the presence of a novel reagent, namely triethyl phosphite-4-dimethylaminopyridine (TEP-4-DMAP), using pyridine as a solvent, at 120-130°C for 6-8 hours.

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A general synthesis of resin-bound triaryl bismuthanes and resin-bound triaryl bismuth diacetates starting from commercially available chloromethyl polystyrene is reported. For the first time resin-bound bismuth has been utilized as part of a multidirectional linker system for solid-phase organic synthesis and as a resin-bound arylation reagent.

N-(substituted-benzoyl)-1-aminonaphthalenes and N-(substituted-benzoyl)-2-aminonaphthalenes (1-NBAs and 2-NBAs) with varied substituents at the para- or meta-position of benzoylphenyl ring were prepared to probe the difference between 1-aminonaphthalene (1-AN) and 2-aminonaphthalene (2-AN) as electron donors, using benzanilide-like charge transfer as a probe reaction. An abnormal long-wavelength emission was found for all of the prepared aminonaphthalene derivatives in cyclohexane and was assigned to the CT state by the observation of a substantial red shift with increasing solvent polarity or with increasing electron-withdrawing ability of the substituent. The CT emission energies were found to follow a linear relationship with the Hammett constant of the substituent and the value of the linear slope for 1-NBAs (-0.45 eV) was higher than that of 2-NBAs(-0.35 eV), the latter being close to that of the aniline derivatives (BAs, -0.345 eV). This pointed to a higher extent of charge separation in the CT state of 1-NBAs in which a full charge separation was established by the reduction potential dependence of the CT emission energy with a linear slope of -1.00. The possible contribution of the difference in the steric effect and the electron donating ability of the donors in 1-NBAs and 2-NBAs was ruled out by the observation that the corresponding linear slopes of benzoyl-substituted BAs remained unchanged when para-, meta-, ortho-, or ortho, ortho-methyls were introduced into the aniline moiety. It was therefore concluded that 1-AN enhanced the charge transfer in 1-NBAs and the proximity of its 1La and 1Lb states was suggested to be responsible. Results showed that the charge transfers in 1-NBAs and 2-NBAs were not the same and 1-AN and 2-AN as electron donors were different not only in electron donating ability but in shaping the charge transfer pathways as well.

Aromatic amides have been prepared with high to moderate yields by a direct condensation reaction of aromatic carboxylic acids with aromatic amines in the presence of phosphorous acid and iodine in pyridine solution at reflux (about 140-150°), for 5-6 hours.

Kinetic studies on the nucleophilic substitution reaction of S-phenyl thiobenzoates with anilines have been carried out at 55.0 deg C.Effects of substituents in the nucleophile(X), substrate(Y) and leaving groups(Z) are analyzed in terms of Hammett's and Broensted's coefficients, ρi and βi and cross-interaction constants ρij and βij where i and j denote X, Y or Z.The sign of ρXZ (or βXZ) is positive, and accordingly, the transition state(TS) variations with the substituents are consistent with those predicted by the potential energy surface diagram; the magnitude of ρx(βx) and ρxy decreases with a better leaving group, and that of ρz and βz decreases with a stronger nucleophile leading to an earlier TS, in agreement with a normal Hammond effect.The larger magnitudes of ρXY, ρYZ and βXZ suggest that the reaction proceeds by an associative SN2 mechanism.A greater kH/kD value (1.0) is observed with deuterated aniline nucleophiles for a stronger nucleophile and a better leaving group, supporting the earlier TS proposed on the basis of the cross-interaction constants.The inverse secondary kinetic isotope effects obtained preclude involvement of any four-center TS or base catalysis by aniline.

A series of mono-, di-, and trimethylated derivatives of 4-chloro- and 4-methoxybenzanilide was synthesized and evaluated for anticonvulsant activity. This series was prepared in the course of studies designed to examine the relationship between anticonvulsant effects and benzamide structure. The compounds were tested in mice against seizures induced by maximal electroshock (MES) and pentylenetetrazole (scMet), as well as with the rotorod assay for neurologic deficit. In mice dosed intraperitoneally, 4-methoxy-2, 6-dimethylbenzanilide (4) showed a median anticonvulsant potency (ED50) of 18.58 mg/kg in the MES test and a median toxicity (TD50) of 133.72 mg/kg in the rotorod toxicity assay, yielding a protective index (PI = TD50/ED50) of 7.2. In mice dosed orally with 4, the anti-MES ED50 was 27.40 mg/kg and the TD50 dose was determined to be 342.58 mg/kg, resulting in a protective index of 12.5.

3-Aryl-1,2,4-benzotriazines were obtained in good yields by the mercury(II) oxide-oxidation of N-phenylsulfonyl-N''-arylbenzamidrazones prepared from N-(phenylsulfonyl)benzohydrazonoyl chlorides and anilines.From the synthetic viewpoint for benzotriazines, this method may be of high utility on account of the availability of starting materials and higher yields.