33667-91-3

Matrix presented A solid-phase synthesis of trisubstituted 3-alkylamino-1,2,4-triazoles has been developed. The synthesis utilizes immobilized N-acyl-1H-benzotriazole-1-carboximidamides as key intermediates. Cyclization with hydrazines under mild conditio

Amide bonds are one of the underpinning linkages in all living systems and are fundamental within drug discovery. Current methods towards their synthesis frequently rely on the use of dipolar aprotic solvents; however, due to increasingly stringent regula

We report how the rearrangement of highly reactive nitrile imines derived from N-2-nitrophenyl hydrazonyl bromides can be harnessed for the facile construction of amide bonds. This amidation reaction was found to be widely applicable to the synthesis of primary, secondary, and tertiary amides and was used as the key step in the synthesis of the lipid-lowering agent bezafibrate. The orthogonality and functional group tolerance of this approach was exemplified by the N-acylation of unprotected amino acids.

We have recently reported a one-pot procedure for glycosyl amides synthesis using selenocarboxylate as traceless reagent. Herein, we present a further application of selenocarboxylate-azide reaction for amide bond formation on a broader range of substrates, including heterocyclic systems and fatty acid. This method proved to be highly efficient for the synthesis of primary and secondary amides, sulfonamides, imides, phosphoramide and also carbamate.

Treatment of tris-azolium precursor 1 with palladium acetate under thermal conditions provided a CCC-pincer palladium(II) complex (2) bearing three NHCs (one imidazolylidene and two triazolylidenes) and one iodide ligand. Further treatment of complex 2 with an excess of AgSbF6 generates tris(carbene) dicationic palladium complex 3 in which the iodine ligands are exchanged with SbF6 anions and the metal center is stabilized by one acetonitrile ligand. Complexes 2 and 3 were tested in several cross coupling reactions showing high conversions under low catalyst loadings and mild reaction conditions. Additionally, complexes 2 and 3 performed well in the hydrosilylation of terminal alkynes with good selectivity toward the E-isomer.

The invention discloses a method for synthesizing an amide derivative under the catalysis of vanadium, which comprises the following step of: by using a nitro aromatic compound and an ester compound as raw materials, a vanadium compound as a catalyst and magnesium chips as a reducing agent, carrying out amidation reaction in an organic solvent to obtain the amide derivative. The method has the advantages that (1) the nitro aromatic compound which is good in stability, low in price and easy to obtain is used as a nitrogen source; (2) the used catalyst is cheap, easy to obtain and low in toxicity; and (3) the method has good substrate applicability, and is suitable for aromatic nitro compounds, fatty esters and aryl esters containing different substituents.

Herein we describe an alternative and unconventional approach of an aminocarbonylation reaction to access aryl amides from readily available and low-cost arylboronic acids and nitroarenes. Nickel metal can serve as both reductant and catalyst in this direct aminocarbonylation. This protocol exhibits a good functional group compatibility and allows a variety of aryl amides to be synthesized, including several drug-like molecules.

The reaction of trifluoroacetyl amides with Grignard reagent for the substitution of CF3 group with various alkyl or aryl groups is described. A variety of aryl, quinolin-8-yl, and (hetero)alkyl functional groups as well as F, Cl, and Br atoms are well tolerated. These moisture-stable and easily available trifluoroacetyl amides can be conveniently obtained and used as new versatile precursors for isocyanates. The control experiments show that the reaction proceeds via an isocyanate intermediate and/or alkoxide/amide dual anionic intermediate.

The reaction of trifluoroacetyl amides with Grignard reagent for the substitution of CF3 group with various alkyl or aryl groups is described. A variety of aryl, quinolin-8-yl, and (hetero)alkyl functional groups as well as F, Cl, and Br atoms are well tolerated. These moisture-stable and easily available trifluoroacetyl amides can be conveniently obtained and used as new versatile precursors for isocyanates. The control experiments show that the reaction proceeds via an isocyanate intermediate and/or alkoxide/amide dual anionic intermediate.

A series of allyl (1–3) and cinnamyl (4–6) palladium(II) complexes supported by hydroxyl functionalized triazolylidenes have been prepared. All new compounds were fully characterized by means of 1H and 13C NMR spectroscopy, FT-IR and elemental analyses. The new triazolylidene palladium complexes were tested as precatalysts in the coupling of aryl chlorides with boronic acids and the coupling of esters with amines to produce biphenyls and amides, respectively. According to the overall results, complexes 4 and 5 displayed the highest catalytic activity in both coupling processes, providing good to excellent yields under mild reaction conditions and using a wide range of substrates.

Cycling between Au(i) and Au(iii) is challenging, so gold-catalyzed cross-couplings are rare. The (MeDalphos)AuCl complex, which we showed was prone to undergo oxidative addition, is reported here to efficiently catalyze the C-N coupling of aryl iodides and amines. The transformation does not require an external oxidant or a directing group. It is robust and works with a wide scope of aryl iodides and N-nucleophiles under mild conditions. Mechanistic studies, including the NMR and MS characterization of a key aryl amido Au(iii) complex, strongly support a 2e redox cycle in which oxidative addition precedes transmetalation and reductive elimination is the rate-determining step.

The invention discloses a novel preparation method of amide compounds. According to the preparation method, perfluoroalkyl amide is taken as the raw material, a transition metal catalyst is adopted, perfluoroalkyl amide carries out reactions for a while in an organic aprotic solvent at a certain temperature, amide compounds can be obtained high selectively, and the yield is high. The preparation method has the advantages of low cost, high yield, and simple and convenient operation, and can be possibly applied to industrial production.

Esters are valuable electrophiles for cross-coupling due to their ubiquity and ease of synthesis. However, harsh conditions are traditionally required for the effective cross-coupling of ester substrates. Utilizing a recently discovered precatalyst, Pd-catalyzed Suzuki-Miyaura and Buchwald-Hartwig reactions involving cleavage of the C(acyl)-O bond of aryl esters that proceed under mild conditions are reported. The Pd(II) precatalyst is highly active because it is reduced to the Pd(0) active species more rapidly than previous precatalysts.

A mild, efficient and regioselective method for para-amination of activated arenes has been developed through a combination of iron and copper catalysis. A diverse range of products were obtained from an operationally simple one-pot, two-step procedure involving bromination of the aryl substrate with the powerful Lewis acid iron(III) triflimide, followed by a copper(I)-catalysed N-arylation reaction. This two-step dehydrogenative process for the regioselective coupling of aromatic C?H bonds with non-activated amines was applicable to anisole-, phenol-, aniline- and acetanilide-type aryl compounds. Importantly, the arene substrates were used as the limiting reagent and required no protecting-group manipulations during the transformation.

A palladium-catalyzed cross-coupling between aryl esters and anilines is reported, enabling access to diverse amides. The reaction takes place via activation of the C-O bond by oxidative addition with a Pd-NHC complex, which enables the use of relatively non-nucleophilic anilines that otherwise require stoichiometric activation with strong bases in order to react. High yields of aromatic, aliphatic, and heterocyclic products are obtained. A range of activated esters are evaluated in the presence and absence of catalyst, demonstrating that the catalytic methodology substantially increases the types of electrophiles that can be utilized for amide bond formation in the absence of harsh bases.

A TBHP-mediated dehydrogenative cross-oxidative-coupling approach has been developed for the synthesis of N-arylbenzamides from methylarenes and acetanilides. This cross-coupling method is free of transition metal catalysts and ligands, and no extra organic solvents are required, which make it an useful and attractive strategy for the straightforward construction of C-N bonds. Besides, this conversion is an important complement to the conventional C-N forming strategies.

An efficient one-pot synthesis of N-arylbenzamide is described via reaction of phenylboronic acid/aryl bromide with benzamide in the presence of CuI (5?mol%) as catalyst, 4-dimethylaminopyridine (20?mol%) as the ligand, and Cs2CO3(2?mmol) as the base. This protocol was applied to synthesize a small library of N-arylbenzamide in high yields.

A binaphthyl-supported Pd nanoparticles (Pd-BNP)-catalyzed aminocarbonylation of aryl iodides in the presence of carbon monoxide and amines for the synthesis of amides has been developed. This methodology provides an efficient route for the synthesis of a COX-2 enzyme inhibitor having anti-inflammatory activity.

A series of aluminum complexes bearing amidate ligands, including acylamide, sulfonamide, and aryl carbamate, was synthesized. In addition, the optimization of ring-opening polymerization of ε-caprolactone by using these aluminum complexes as catalysts was studied. Polymerization results revealed that steric bulky groups in anilinyl groups decreased the catalytic activity of aluminum sulfonamide complexes but increased that of aluminum-acylamide complexes. Compared with other complexes bearing N-(4-methoxyphenyl) acylamidate and N-(4-methoxyphenyl) p-tolylsulfonamidate, an aluminum complex (MfOMeAlMe2) bearing methyl (4-methoxyphenyl)carbamate had the highest catalytic activity with an ideal molecular weight control and narrow polydispersity index (PDI). Other poly-ε-caprolactones with special end chains, such as PEG-200, 2-dimethylaminoethanol, bis(2-hydroxyethyl) disulfide, 2-((2-hydroxyethyl)disulfanyl)ethyl 2-bromo-2-methylpropanoate, and PEG-polyester-bearing disulfide group, were successfully synthesized using MfOMeAlMe2 as the catalyst. The polymerization of δ-valerolactone and 2-bromo-ε-caprolactone by using BnOH as an initiator and MfOMeAlMe2 as the catalyst resulted in poly-δ-valerolactone and poly-2-bromo-ε-caprolactone, respectively, with a precise molecular weight and a narrow PDI as well as poly-ε-caprolactones.

A highly dispersed nanopalladium catalyst supported on mesocellular foam (MCF), was successfully used in the heterogeneous catalysis of aminocarbonylation reactions. During the preliminary evaluation of this catalyst it was discovered that the supported palladium nanoparticles exhibited a "release and catch" effect, meaning that a minor amount of the heterogeneous palladium became soluble and catalyzed the reaction, after which it re-deposited onto the support. It's catchy! An efficient palladium-catalyzed protocol for the aminocarbonylation of aryl iodides is reported in which the palladium immobilized on the amino-functionalized mesocellular foam (MCF) was found to operate through a "release and catch" mechanism (see scheme). A very low content of palladium was found in solution upon completion of the reaction and a variety of different aryl iodides were converted to the corresponding amides under mild conditions.

Hormone-sensitive lipase (HSL) is a critical enzyme involved in the hormonally regulated release of fatty acids and glycerol from adipocyte lipid stores. Its inhibition may improve insulin sensitivity and blood glucose handling in type 2 diabetes. Accordingly, many small-molecule HSL inhibitors have recently been identified. In continuation of our efforts for discovery of new HSL inhibitors, we prepared a variety of esters, amides, sulfonamides and sulfonate esters capable of fitting two pharmacophore models that we developed and published earlier. The tested compounds were synthesized via coupling reactions of aroyl chlorides or sulfonyl chlorides with phenols, amines and related derivatives. Our efforts led to the identification of interesting compounds of low micromolar anti-HSL bioactivities, which have potential to be developed into effective antidiabetic agents.

An atom-efficient and transition metal-free approach to amides from the corresponding benzyl hydrocarbons through C-H and C-C bond cleavage has been developed. Mechanistic studies have shown that a DDQ-promoted cross-dehydrogenative coupling (CDC) reaction with subsequent oxidation and rearrangement are involved in this transformation. The Royal Society of Chemistry.

A new series of substituted 1,2,4-triazole derivatives have been synthesized using substituted imido derivatives and isonicotinyl hydrazine (or 4-nitrobenzoylhydrazine) as the key intermediates. These compounds include different donor or acceptor substitu

An efficient and mild method using a bimetallic MnF2/CuI catalyst at 60 °C in water was developed for the N-arylation of amides and sulfonamides with aryl halides. A variety of functionalized amides and sulfonamides were coupled with different substituted aryl halides to afford the corresponding N-arylated products in good to excellent yields (up to 97 %). An efficient method using a bimetallic MnF2/CuI catalyst in combination with trans-1,2-diaminocyclohexane as the ligand has been developed for the cross-coupling of benzamides and sulfonamides with differently substituted aryl iodides in water. The corresponding N-arylated products were obtained in good to excellent yields (up to 97 %) under the catalytic conditions. Copyright

Chlorodiphenylphosphine, imidazole, and molecular iodine in refluxing dichloromethane are used for the efficient preparation of amides under mild reaction conditions. This reagent system also shows excellent selectivity for mono-N-alkylation of amines with alcohols. In this system, the resulting phosphorus byproduct (diphenylphosphinic acid) is easily removed by extraction using an aqueous basic solution in the workup processes, which avoids the tedious and time-consuming chromatographic methods.

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.

Cu2O nanoparticles/DMEDA (N,N′-dimethylethylenediamine) was proved to be an efficient catalyst system for amidation of aryl halides under mild condition. This method displayed excellent selectivity and the catalyst was recyclable without loss of activity. The low cost, simple operation and excellent yields make this approach attractive for industrial applications. Cu2O nanoparticles/DMEDA (N,N′-dimethylethylenediamine) was proved to be an efficient catalyst system for amidation of aryl halides under mild condition. This method displayed excellent selectivity and the catalyst was recyclable without loss of activity. The low cost, simple operation and excellent yields make this approach attractive for industrial applications. Copyright

On the basis of a hit from random screening, biaryl amide derivatives were prepared in a combinatorial manner via parallel solution-phase synthesis, and their effects on melanocytes were investigated to discover new effective skin depigmenting agents. Amo

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).

Reactions of secondary amides 2a-i with 1-chloro-1H-benzotriazole and triphenylphosphine give imidoylbenzotriazoles 3a-i. The treatment of 3a,b,e,g with silyl enol ethers 5a,b in the presence of potassium tert-butoxide provides a new general approach to enaminoketones 6a-h.

A series of Xantphos-based ligands containing various substituents in the diphenylphosphino groups were synthesized, and their effect on the product yield and ratio in the palladium-catalyzed arylation of ureas with nonactivated aryl halides was studied. The arylation of urea and phenylurea in the presence of Pd2(dba)3-CHCl3, 3,5-(CF3) 2Xantphos, and Cs2CO3 in dioxane at 100°C gave the corresponding N,N′-diarylureas in 62-98% yield.

Several amides were obtained in high yields by an efficient method from the corresponding imines which are readily prepared from aldehydes. This procedure involves the oxidation of aldimines with m-CPBA and BF3·OEt2. In this reaction, the product is strongly influenced by the electron releasing capacity of the aromatic substituent.

Nucleophilic substitution reactions of benzoic anhydrides, in which one of the rings is substituted, with anilines were investigated in methanol.The product-formation step coincides with the rate-limiting step so that the two rate constants, kXY and kXZ, for the competitive reaction pathways can be dissected.The two cross-interaction constants, ρXY and ρXZ, especially an unusually large magnitude of the latter, indicate that the reaction proceeds by a frontside SN2 attack on either one of the carbonyl carbon with a strong interaction between the nucleophile (X) and the leaving group (Z).The mechanism is also supposed by the trends in the activation parameters.

A series of 4-(benzothiazol-2-yl)benzylphosphonic acid dialkyl ester were synthesized and evaluated for coronary vasodilatory activity by Langendorff's method in the isolated guinea pig heart. Many of the phosphonic acid dialkyl esters exhibited vasodilat

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.