6833-18-7

A new generation of saturated benzene mimetics, 2-oxabicyclo[2.1.1]hexanes, was developed. These compounds were designed as analogues of bicyclo[1.1.1]pentane with an improved water solubility. Crystallographic analysis of 2-oxabicyclo[2.1.1]hexanes revea

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.

A metal-free heterogeneous photocatalysis has been developed for the synthesis of benzothiazoles via intramolecular C-H functionalization/C-S bond formation of thiobenzanilides by inexpensive graphitic carbon nitride (g-C3N4) under visible-light irradiation. This reaction provides access to a broad range of 2-substituted benzothiazoles in high yields under an air atmosphere at room temperature without addition of a strong base or organic oxidizing reagents. In addition, the catalyst was found to be stable and reusable after five reaction cycles.

A general electrochemical system for reductive hydrodefunctionalization is described, employing the inexpensive and easily available triethylamine (Et3N) as a sacrificial reductant. This protocol is characterized by facile operation, sustainable conditions, and exceptionally wide substrate scope covering the cleavage of C-halogen, N-S, N-C, O-S, O-C, C-C and C-N bonds. Notably, the selectivity and capability of reduction can be conveniently switched by simple incorporation or removal of an alcohol as a co-solvent.

The invention discloses a selective hydrogenation dehalogenation method of copper-catalyzed ortho-halogenated acylaniline. The method comprises the following steps: by using ortho-halogenated acylaniline as a starting raw material and copper acetylacetonate/vasicine as a catalyst, adding an organic alkali, reacting in an alcoholic solution at 80-100 DEG C for 12 hours, and regioselectively catalytically hydrogenating ortho-bromine and iodine atoms. The preparation method has the characteristics of simplicity and convenience in operation, wide substrate application range, low cost, high regioselectivity and the like, and has practicability.

In present work, we have explored a Cu(acac)2/vasicine-catalyzed regioselective hydrodehalogenation methodology of o-haloanilides using EtOH as hydrogen source and solvent. The catalytic system could selectively dehalogenate 2-Br and 2-I, and features regioselective, efficient and functional group tolerance.

The invention relates to a preparation method of an amide, wherein, under the action of oxygen, the isothiocyanate and the aldehyde can react to form an amide, and the reaction temperature can be effectively increased only when not less than 110 °C. This process is also suitable for the reaction of isocyanates with aldehydes to produce amides. The preparation method is cheap in raw material, wide in substrate application range and free of metal catalysts in the reaction process. The initiator or other activator is green and economical, and can effectively reduce the cost.

A visible-light-promoted and simple iron salt-catalyzed N-arylation was achieved efficiently under external photosensitizer-free conditions. Arylboronic acids and bench-stable dioxazolones were used for this cross-coupling reaction. This reaction features high reactivity, wide substrate scope, good functional group tolerance, simple operation procedure, and mild reaction conditions. Preliminary mechanistic investigations were conducted to support a radical pathway. This method may contribute to shift the paradigm of iron-catalyzed C-N bond construction and nitrene transfer chemistry.

Palladium-catalyzed Hiyama coupling of active thioureas via selective C-N bond cleavage is reported. Notably, the new approach employed active thioureas as coupling partners in the presence of arylsilanes to give amides in good yield. Further, this strategy, which utilized CuF 2as a key oxidant and activator, afforded various amide products under mild conditions and an easy to handle procedure without extra base.

A visible-light-driven photoredox-catalyzed nonaqueous oxidative C-N cleavage of N,N-dibenzylanilines to 2° amides is reported. Further, we have applied this protocol on 2-(dibenzylamino)benzamide to afford quinazolinones with (NH4)2S2O8 as an additive. Mechanistic studies imply that the reaction might undergo in situ generation of α-amino radical to imine by C-N bond cleavage followed by the addition of superoxide ion to form amides.

A new approach for amide bond formation via a mild and efficient Iron-catalyzed cross-coupling reaction of acylhydrazines and amines using TBHP as oxidant is described. This protocol is compatible with a wide range of amines and acylhydrazines. In addition, the synthetic application of the reaction is presented.

N-Acyl lactam amides, such as benzoylpyrrolidin-2-one, benzoylpiperidin-2-one, and benzoylazepan-2-one reacted with amines in the presence of DTBP and TBAI to afford the transamidated products in good yields. The reactions were conducted under aqueous conditions and good functional group tolerance was achieved. Both aliphatic and aromatic primary amines displayed good activity under metal-free conditions. A radical reaction pathway is proposed.

A facile one-pot synthesis of amides from N-Alloc-, N-Boc-, and N-Cbz-protected amines has been described. The reactions involve the use of isocyanate intermediates, which are generated in situ in the presence of 2-chloropyridine and trifluoromethanesulfonyl anhydride, to react with Grignard reagents to produce the corresponding amides. Using this reaction protocol, a variety of N-Alloc-, N-Boc-, and N-Cbz-protected aliphatic amines and aryl amines were efficiently converted to amides with high yields. This method is highly effective for the synthesis of amides and offers a promising approach for facile amidation.

Amides are prevalent in nature and valuable functional compounds in agrochemical, pharmaceutical, and materials industries. In this work, we developed a selective and mild method for the synthesis of N-aryl amides. Starting from commercially available nitroarenes and acyl halides, N-aryl amides with good yields can be obtained in water. Especially in the process of transformation, Fe dust is the only reductant and additive, and the reaction can be easily performed on a large scale.

Amides are important structural motifs in pharmaceutical and agrochemical chemistry because of the intriguing biological active properties. We report here the amidation of commercially available esters with anilines that was promoted by low-cost and air-stable chromium(III) pre-catalyst combined with magnesium, providing access to amides. This reaction occurs without the use of external ligands in a simple operation. Mechanistic studies indicate that a reactive aminated Cr species responsible for the amidation can be considered, which may be formed by reaction of low-valent Cr with aniline followed by reduction with hydrogen evolution.

A magnetite-reduced graphene oxide-supported CuO nanocomposite (rGO/Fe3O4-CuO) was preparedviaa facile chemical method and characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV-vis spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Brunauer-Emmett-Teller (BET) analysis, vibrating-sample magnetometry (VSM), and thermogravimetric (TG) analysis. The catalytic activity of the rGO/Fe3O4-CuO nanocomposite was probed in the direct oxidative amidation reaction of methylarenes with free amines. Various aromatic and aliphatic amides were prepared efficiently at room temperature from cheap raw chemicals usingtert-butyl hydroperoxide (TBHP) as a “green” oxidant and low-toxicity TBAI in water. This method combines the oxidation of methylarenes and amide bond formation into a single operation. Moreover, the synthesized nanocomposites can be separated from the reaction mixtures using an external magnet and reused in six consecutive runs without a noticeable decrease in the catalytic activity.

In this paper, a NaOtBu-mediated synthesis approach was developed for direct amidation of unactivated esters with amines under transition-metal-free and solvent-free conditions, affording a series of amides in good to excellent yields at room temperature. In particular, an environmentally friendly and practical workup procedure, which circumvents the use of organic solvents and chromatography in most cases, was disclosed. Moreover, the gram-scale production of representative products3a,3wand3auwas efficiently realized by applying operationally simple, sustainable and practical procedures. Furthermore, this approach was also applicable to the synthesis of valuable molecules such as moclobemide (a powerful antidepressant), benodanil and fenfuram (two commercial agricultural fungicides). These results demonstrate that this protocol has the potential to streamline amide synthesis in industry. Meanwhile, quantitative green metrics of all the target products were evaluated, implying that the present protocol is advantageous over the reported ones in terms of environmental friendliness and sustainability. Finally, additional experiments and computational calculations were carried out to elucidate the mechanistic insight of this transformation, and one plausible mechanism was provided on the basis of these results and the related literature reports.

Through a screen of over one hundred and 30 permutations of reaction temperatures, solvents, carbodiimide resins, and carbodiimide molar equivalences, in the presence, absence, or combination of diisopropylamine and benzotriazole additives, a convenient and first reported carbodiimide polymer-assisted flow approach to effect amide coupling and lactamization was developed. The protocol entails injecting a single solution (1:9 dimethylformamide: dichloromethane) containing a carboxylic acid and an amine or linear peptide sequence into a continuous stream of dichloromethane. The protocol remained viable in the absence of base, did not require carboxylate preactivation which, and in concert with minimal workup requirements, enabled the isolation of products in high yields. Compared to the utilization of untethered carbodiimide reagents, the flow procedure was also observed to provide a degree of racemization safety.

Copper-catalyzed amidation/dimerization of anilides via regioselective C(sp2)-H functionalization is achieved. The para-selective amidation is accomplished on the anilide aromatic ring via a radical pathway leading to C-N bond formation in the presence of ammonium persulfate as a radical source/oxidant for the copper catalyst. The developed protocol tolerates a wide range of anilide substrates. The regioselectivity is confirmed by single-crystal X-ray studies.

Imidoyl sulfoxonium ylides are presented for the first time as potential precursors to generate α-imino metal-carbene intermediates and applied in direct C-H functionalization reactions catalyzed by [Ir(cod)Cl]2 (4 mol %) to provide 2-substituted indoles (up to 70% yield) in just one step. This class of sulfur ylide is successfully obtained from imidoyl chloride and dimethylsulfoxonium methylide (23 new examples in 45-85% yield) or by imino group formation from the corresponding β-keto sulfoxonium ylides and anilines in the presence of TiCl4 as a Lewis acid (9 examples in 33-94% yield).

Hydroxyl compounds serve as key building blocks in the preparation of biologically active natural products and drugs. Traditionally, hydroxylation of the aromatic ring is achieved using stoichiometric amounts of oxidants, which leads to low atom-economy, undesired by-products, potential explosion risk and environmental pollution. Recently, electrosynthesis has attracted increasing attention as it employs clean electrical energy to promote redox reactions avoiding the use of oxidants. However, due to the poor mass and heat transfers of batch cells, low productivity and selectivity limit its further application. Herein, we develop a catalyst-, oxidant-, acidic solvent- and quaternary ammonium salt-free electrochemical para-selective hydroxylation of N-arylamides at room temperature in batch and continuous-flow. This proposal features excellent position control and water, air and functional group tolerance. Also, it is easy to scale up with higher productivity and selectivity using a flow electrolysis cell.

The transamidation of tertiary amides was achieved via nickel catalysis in combination with briphos ligands. N-Methyl-N-phenylbenzamide derivatives reacted with primary amines in the presence of NiCl2/briphos L4 to provide the transamidated products in moderate to good yields. Primary aromatic amines delivered higher product yields than aliphatic amines.

In the present work, we have developed a practical methodology for the hydrodehalogenation of o -haloanilides using PdCl 2at 100 °C under mild conditions in water. The catalytic system could selectively dehalogenate both aryl chloride and aryl bromide and exhibit a broad functional group tolerance.

An unprecedented N-demethylation of N-methyl amides has been developed by use of N-fluorobenzenesulfonimide as an oxidant with the aid of a copper catalyst. The conversion of amides to carbinolamines involves successive single-electron transfer, hydrogen-atom transfer, and hydrolysis, and is accompanied by formation of N-(phenylsulfonyl)benzenesulfonamide. Carbinolamines spontaneously decompose to N-demethylated amides and formaldehyde, because of their inherent instability.

The invention discloses an N-demethylation method for amide and application thereof. The method comprises the following steps: heating raw amide to 40-120 DEG C under the action of N-fluorodibenzenesulfonamide and a bivalent copper salt, and carrying out a reaction to obtain demethylated amide. The chemical structural formula of the raw amide is described in the specification; the chemical structural formula of the demethylated amide is described in the specification; and in the formulas, R1 is selected from aryl, alkyl and alkenyl groups, and R2 is selected from aryl, alkyl and alkenyl groups. With the method, N-demethylation of amide can be achieved; and the method has the advantages of mild reaction conditions, easiness in operation, low cost and the like.

A versatile and environmentally friendly synthetic method for the formation of acyl phosphates is reported. By employing electrochemical oxidative dehydrogenative coupling, this transformation features a broad range of substrates, as well as metal-free, o

The decarboxylative/oxidative amidation of aryl α-ketocarboxylic acids with 5-aryl-3-nitroisoxazole-4-carboxylates and substituted dinitrobenzenes under oxidative aqueous conditions to afford N-aryl amides is described. The reaction is suggested to proceed via a radical pathway in which a benzoyl nitroxyl radical, the key intermediate formed from reaction between nitroarene and benzoyl radical from glyoxalic acid, couples with hydroxyl radical from water to produce amide. Mechanistic insight allowed the scope of the strategy to be expanded to the synthesis of amides via reaction between aryl α-ketocarboxylic acids and nitroso compounds.

Few half-sandwich (η6-p-cymene) ruthenium(II) complexes supported by benzothiazole hydrazone Schiff bases were synthesized. The new complexes possess the general formulae [Ru(η6-p-cymene)(L)Cl] (1-3) (L = salicyl((2-(benzothiazol-2-yl)hydrazono)methylphenol) (SAL-HBT), 2-((2-(benzothiazol-2-yl)hydrazono)methyl)-6 methoxyphenol) (VAN-HBT) or naphtyl-2-((2-(benzothiazol-2-yl)hydrazono)methyl phenol) (NAP-HBT). All compounds were fully studied by analytical, spectroscopic techniques (IR, NMR) and also by mass spectrometry. The solid state structure of the complex 3 reveals the coordination of p-cymene moieties with ruthenium(II) in a three-legged piano-stool geometry along with benzothiazole hydrazone Schiff base ligand in a monobasic bidentate fashion. The catalytic properties of the complexes were screened in transamidation of primary amide with amines after optimization with respect to solvent, substituents, time and catalyst loading. The results show that the complex 3 is the most efficient catalyst for the transamidation of carboxamides with amines.

A Cu-catalyzed oxidative amidation of simple ketones with amines via carbon-carbon (C-C) bond cleavage has been developed. A number of aryl and alkyl ketones could be easily converted to amides using cheap copper salt as the catalyst and O2 as the oxidant with a wide range of amines, including primary and secondary amines. This method shows a notable advantage of the broad scope for the substrate, thus providing a practical approach to amides. A plausible mechanism is proposed based on the preliminary experiments.

Magnetically separable and reusable Fe/Cu oxide (Fe3O4-Cu2O) nanoparticles were employed as an efficient catalyst for the arylation of benzamide, which was carried out with a range of both arylboronic acid and benzamide to afford N-arylamide in good to excellent yield.

The construction of amide bonds and peptide linkages is one of the most fundamental transformations in all life processes and organic synthesis. The synthesis of structurally ubiquitous amide motifs is essential in the assembly of numerous important molecules such as peptides, proteins, alkaloids, pharmaceutical agents, polymers, ligands and agrochemicals. A method of SO2F2-mediated direct clickable coupling of carboxylic acids with amines was developed for the synthesis of a broad scope of amides in a simple, mild, highly efficient, robust and practical manner (>110 examples, >90% yields in most cases). The direct click reactions of acids and amines on a gram scale are also demonstrated using an extremely easy work-up and purification process of washing with 1 M aqueous HCl to provide the desired amides in greater than 99% purity and excellent yields.

By taking the advantage of PPh3/Selectfluor system, carboxylic acids are efficiently converted into the pivotal intermediates acyloxyphosphonium ions that can selectively react with a second carboxylic acid or fluoride to in situ yield the corresponding acid anhydrides or acyl fluorides. The developed protocol features commercially availabile reagents, no involvement of base, room temperature conditions, and simple experimental procedure. Additionally, various amides or esters are readily achieved, respectively, with the addition of amines or alcohols.

Chemoselective N-acylation of amines with carboxylic acids as acyl electrophiles and Br?nsted acidic IL [BMIM(SO3H)][OTf] as promoter is reported under both thermal and microwave irradiation to produce libraries of carboxamides in good to excellent yields after a simple workup. The protocol is compatible with structurally diverse 1° and 2° amines and works in the presence of sensitive functional groups such as thiols and phenols. The potential for recycling and reuse of the IL is also demonstrated.

A general, economical, and environmentally friendly method of amide synthesis from phenyl esters and aryl amines was developed. This new method has significant advantages compared to previously reported palladium-catalyzed approaches. The reaction is performed transition metal- and solvent-free, using a cheap and environmentally benign base, NaH. This approach enabled us to obtain target amides in high yields with high atom economy.

Visible-light-driven, intramolecular C(sp2)-H thiolation has been achieved without addition of a photosensitizer, metal catalyst, or base. This reaction induces the cyclization of thiobenzanilides to benzothiazoles. The substrate absorbs visible light, and its excited state undergoes a reverse hydrogen-atom transfer (RHAT) with 2,2,6,6-tetramethylpiperidine N-oxyl to form a sulfur radical. The addition of the sulfur radical to the benzene ring gives an aryl radical, which then rearomatizes to benzothiazole via RHAT.

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 invention discloses an N-heterocyclic carbene palladium complex crystal, a synthetic method thereof and application thereof in preparation of amide compounds. The structural formula of the complexcrystal is shown in the specification, or the complex crystal is prepared from an N-heterocyclic carbene ligand, Pd(CH3CN)2Cl2 and Ag2O in acetonitrile serving as a solvent. The N-heterocyclic carbene palladium complex crystal is relatively stable, wherein the raw materials used in the synthesis method are cheap and easy to obtain, so that the synthetic method is simple, convenient and easy to implement is simple in post-treamtent and is high in yield; and the N-heterocyclic carbene palladium complex crystal is used for catalyzing carbonylation carbon-nitrogen bond coupling reaction to prepare amide compounds and is high in catalytic activity, easy to operate and high in atom economy.

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.

The formation of amide bonds is one of the most valuable transformations in organic synthesis. Beckmann rearrangement is a well-known method for producing secondary amides from ketoximes. This study demonstrates the rapid synthesis of ketoximes and amides in microdroplets. Many factors are found to affect the yield, such as microdroplet generation devices, temperature, catalysts, and concentrations of reactants. In particular, the temperature has a great influence on the synthesis of amide, which is demonstrated by a sharp ascendance to the yield when the temperature was increased to 45 °C. The best amide yield (93.3%) can be obtained by using coaxial flowing devices, a sulfonyl chloride compound as a catalyst, and heating to 55 °C in microdroplets. The yields can reach 78.7-91.3% for benzoylaniline and 87.2-93.4% for benzophenone oximes in several seconds in microdroplets compared to 10.1-66.1% and 82.5-93.3% in several hours in the bulk phase. Apart from the dramatically decreased reaction time and enhanced reaction yields, the microdroplet synthesis is also free of severe reaction environments (anhydrous and anaerobic conditions). In addition, the synthesis in microdroplets also saves reactants and solvents and reduces the waste amounts. All of these merits indicate that the microdroplet synthesis is a high-efficiency green methodology.

o-Phthalic anhydride/Zn(OTf)2 co-catalyzed Beckmann rearrangement was developed, producing the corresponding amide in up to 99% yield with acid-sensitive functionalities tolerated well, and the scale of the reaction could be enlarged to 77 mmol and the excellent yield was maintained. A successive procedure was developed. Moreover, the reaction was carried out at rt under nearly neutral conditions, and the workup was concise. These features illustrated the potential of the protocol in amide synthesis.

Isocyanates are useful building blocks for the synthesis of amides, although their widespread use has been limited by their high reactivity, which often results in poor functional group tolerance and a propensity to oligomerize. Herein, a rhodium-catalyzed synthesis of amides is described coupling boroxines with blocked (masked) isocyanates. The success of the reaction hinges on the ability to form both the isocyanate and the organorhodium intermediates in situ. Relying on masked isocyanate precursors and on the high reactivity of the organorhodium intermediate results in broad functional group tolerance, including protic nucleophilic groups such as amines, anilines, and alcohols.

Graphene oxide (GO)-catalyzed selective synthesis of amides via CSp3–H activation of methylarenes and consequent C–N bond formation with anilines under aqueous medium has been described. Oxygen functionality allied with GO surface played a dual role both as acid catalyst and oxidizing agent to some extent. However, GO has a copious effect on the reaction, shown by a high TOF value with TBHP as co-oxidant. The decisive role of carboxylic acid functional groups on GO nanosheets in this metal-free strategy has been confirmed and was monitored by various analytic techniques viz. Fourier transform-infrared, UV–Vis, Raman and XPS. A plausible mechanism was proposed by control experiments and by the isolation of the intermediate. Over-oxidation of methylarenes was not detected, and high recyclability of the carbocatalyst with its heterogeneous behavior facilitated the isolation and purification of the desired products. We have further explored the utility of this process for the chemoselective synthesis of benzimidazoles.

The amide bond is one of the most fundamental functional groups in chemistry and biology and plays a central role in numerous processes harnessed to streamline the synthesis of key pharmaceutical and industrial molecules. Although the synthesis of amides is one of the most frequently performed reactions by academic and industrial scientists, the direct transamidation of tertiary amides is challenging due to unfavorable kinetic and thermodynamic contributions of the process. Herein, we report the first general, mild, and highly chemoselective method for transamidation of unactivated tertiary amides by a direct acyl N-C bond cleavage with non-nucleophilic amines. This operationally simple method is performed in the absence of transition metals and operates under unusually mild reaction conditions. In this context, we further describe the direct amidation of abundant alkyl esters to afford amide bonds with exquisite selectivity by acyl C-O bond cleavage. The utility of this process is showcased by a broad scope of the method, including various sensitive functional groups, late-stage modification, and the synthesis of drug molecules (>80 examples). Remarkable selectivity toward different functional groups and within different amide and ester electrophiles that is not feasible using existing methods was observed. Extensive experimental and computational studies were conducted to provide insight into the mechanism and the origins of high selectivity. We further present a series of guidelines to predict the reactivity of amides and esters in the synthesis of valuable amide bonds by this user-friendly process. In light of the importance of the amide bond in organic synthesis and major practical advantages of this method, the study opens up new opportunities in the synthesis of pivotal amide bonds in a broad range of chemical contexts.

An efficient strategy for the synthesis of benzamides from acetamides and aryl iodides using 1?mol% Pd (OAc)2 as catalyst and Cr (CO)6 as CO-precursor is described. This new synthetic methodology displays high functional group tolerance on both substrates and avoids the need for ligands, reducing agents, or other additives. The corresponding products were obtained in good to excellent yields at atmospheric pressure under mild reaction conditions.

Amide bond formation is one of the most important basic reactions in chemistry. A catalyst-free approach for constructing amide bonds from thiocarboxylic acids and amines was developed. The mechanistic studies showed that the disulfide was the key intermediate for this amide synthesis. Thiobenzoic acids could be automatically oxidized to disulfides in air, thioaliphatic acids could be electro-oxidized to disulfides, and the resulting disulfides reacted with amines to give the corresponding amides. By this method, various amides could be easily synthesized in excellent yields without using any catalyst or activator. The successful synthesis of bioactive compounds also highlights the synthetic utility of this strategy in medicinal chemistry.

Here, we report a chromium-catalyzed activation of acyl C-O bonds with magnesium for amidation of esters with nitroarenes. Low-cost chromium(III) chloride shows high reactivity in promoting amidation by using magnesium as reductant and chlorotrimethylsilane as additive. It provides a step-economic strategy to the synthesis of centrally important amide motifs using inexpensive and air-stable nitroarenes as amino sources.

A general Pd-catalyzed synthesis of amides by oxidative aminocarbonylation of arylsilanes under mild conditions was accomplished for the first time. The reaction is promoted by a commercially available copper(II) fluoride, which acts as a dual silane activator and mild oxidant, enabling highly efficient aminocarbonylation of versatile arylsilanes at atmospheric CO pressure. The reaction is tolerant of a wide range of arylsilanes and various sensitive halide functional groups as well as a broad scope of amines are compatible with this oxidative process using cheap CO. A significant aspect involves the increased efficiency by the catalyst system. The reaction represents a segue into the powerful Pd-catalyzed oxidative transformations of organosilanes.

The invention discloses a secondary/tertiary amide compound and a synthesis method thereof. The method comprises the following steps: adding arylsilane and an amine compound, a catalyst and an additive to a solvent, introducing CO under a certain pressure, carrying out a carbonylation reaction, and carrying out separation and purification to obtain the secondary/tertiary amide. The method for preparing the secondary/tertiary amide by the carbonylation reaction has the advantages of concision, high efficiency, directness in the reaction, high atom economy, and wide sources and good stability ofa substrate. The reaction system of the invention does not require inert gas protection, and has mild conditions, and the target product is easy to separate and the yield reaches up to 92% under optimized reaction conditions.

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.