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The metal‐free catalytic hydrogenation of secondary carboxylic acid amides is developed. The reduction is realized by two new catalytic reactions. First, the amide is converted into the imidoyl chloride by triphosgene (CO(OCCl3)2) using novel phosphorus(V) catalysts. Second, the in situ generated imidoyl chlorides are hydrogenated in high yields by an FLP‐catalyst. Mechanistic and quantum mechanical calculations support an autoinduced catalytic cycle for the hydrogenation with chloride acting as unusual Lewis base for FLP‐mediated H2‐activation., The hydrogenation of secondary carboxylic acid amides by combined phosphane oxide and frustrated Lewis pair catalysis is described. The reaction proceeds under mild conditions and displays excellent functional group tolerance. Kinetic and quantum‐chemical experiments support the autoinduced catalytic cycle with chloride as active Lewis base for the hydrogen activation.

An efficient synthesis of substituted 3,4-dihydroisoquinolinones through [4+2]-annulation of N-chlorobenzamides/acrylamides having a monodentate directing group with alkylidenecyclopropanes in the presence of a less expensive, highly abundant and air stable Co(III) catalyst via a C–H activation is demonstrated. In this reaction, the N–Cl bond of N-chlorobenzamide serves as an internal oxidant and thus an external metal oxidant is avoided. The 3,4-dihydroisoquinolinone derivatives are converted successfully into the highly useful imidoyl chloride derivatives. The deuterium labeling and kinetic isolabelling studies reveal that the C–H activation is a rate-determining step in this cyclization reaction.

Redox-active esters (RAEs) as active radical precursors have been extensively studied for C-B bond formations. However, the analogous transformations of stabilized radicals from the corresponding acid precursors remain challenging owing to the strong preference towards single-electron oxidation to the stable carbocations. This work describes a general strategy for rapid access to various aliphatic and aromatic boronic esters by mild photoinduced decarboxylative borylation. Both aryl and alkyl radicals could be generated from the leaving group-assisted N-hydroxybenzimidoyl chloride esters, even α-CF3 substituted substrates could be activated for further elaboration.

A new effective method for the construction of nitrogen heterocycles incorporating endocyclic pharmacophore sulfonamide fragment, based on the use of easy accessible N-(chlorosulfonyl)imidoyl chloride, CCl3C(Cl)=NSO2Cl (1), has been developed. Thus, a reaction of 1 as bielectrophilic 1,3-C&ndash, N&ndash, S reagent with benzylamines that act as 1,4-N&ndash, C&ndash, C-C binucleophiles, affords respective 1,2,4-benzothiadiazepine-1,1-dioxides. On the other hand, 1 reacts with alkenyl amines with the formation of respective N-alkenyl amidines undergoing Lewis acids initiated intramolecular cyclization to afford derivatives of 1,2,4-thiadiazines and 1,2,4-thiadiazocines bearing a halomethyl group able for further functionalization. The first examples of electrophilic heterocyclization of the chlorosulfonyl group onto an alkenyl or alkynyl group have been revealed.

p-Sulphonic-N-propionyl aniline 3 was produced from sulphanilic acid with propionic acid under reflux for 2 h, then the compound 3 reacted with thionyl chloride and the corresponding imidoyl chloride 4 was obtained. When imidoyl chloride 4 reacted with potassium isothiocyanate and aniline, the corresponding thiourea derivatives 6 was produced. Compound 6 was reacted with tricyanovinylamine to produce the thiazole derivative 7 after cyclization. The microwave-assisted condensation of 2,3,4.6,-tetra-O-acetyl-β-D-glucopyranosylisothiocynate 8 with thiazole derivative 7 afforded the thiourea derivatives 9. Compound 10 a, b has been synthesized by reacting thiourea derivatives 9 with chloroacetone. The prepared compounds were screened for antibacterial properties against Staphylococcus aureus and Escherichia coli, and antifungal activity against Candida sp. The structure assignments of the new synthesized compounds are based on spectroscopic data.

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).

A new triketimine (2,6-Me2C6H3N=CMe)2CH(2,6-Me2C6H3N=CBut) (1) was synthesized by the reaction of imidoyl chloride 2,6-Me2C6H3N=CClBut with lithium diketiminate (2,6-Me2C6H3N=CMe)2CHLi. In the crystalline state, compound 1 exists in the diimineenamine form; in solution, in the triimine form. The metalation of triketimine 1 with n-butyllithium in THF at 0 °C produced lithium triketiminate [(2,6-Me2C6H3N=CMe)2C(2,6-Me2C6H3N=CBut)]Li(THF)2 (2). The metathesis reactions of Ln(BH4)3(THF)3 (Ln = Y, Nd) with compound 2 (1: 1 molar ratio, THF) gave the neutral triketiminate bis(borohydride) complexes [(2,6-Me2C6H3N=CMe)2C(2,6-Me2C6H3N=CBut)]Ln(BH4)2(THF)2 (Ln = Y (3), Nd (4)). As opposed to the complexes with neutral triketimine, the monoanionic triketiminate ligand is coordinated to Li and Y or Nd cations in a bidentate fashion. Complexes 3 and 4 catalyze the polymerization of rac-lactide and e-caprolactone; in combination with [Ph3C][B(C6F5)4] and AlBu3 i (1 : 1 : 10 molar ratio), these compounds exhibit catalytic activity in the polymerization of isoprene.

In this paper we investigated reactions of urazole and phthalazine with N-(aryl)-2,2,2-trifluoroacetimidoyl chloride derivatives. Results showed that when imidoyl chloride derivative has a fluorine atom at ortho position (3a–c), in two steps under a SNi mechanism and then SNAr reaction mechanism produce ayl-5-(trifluoromethyl)-1H-benzo[e][1,2,4]triazolo[1,2-a][1,2,4]triazine-1,3(2H)-diones (4a–c) and 6-(trifluoromethyl)benzo[5,6][1,2,4]triazino[1,2-b]phthalazine-8,13-diones (4i,4j) in good to excellent yields. In the other imidoyl derivatives (3d–h and 3i,3j) under these conditions cyclization reaction does not occur and therefore produce 1-aryl-2,2,2-trifluoromethyl)-4-phenyl-1,2,4-triazolidine-3,5-diones (4d–h) and 2-(2,2,2-trifluoro-1-(arylimino)ethyl)-2,3-dihydrophthalazine-1,4-diones(4k,4l) (non-cyclic products) in good to excellent yields.

Partially fluorinated triazole derivatives were synthesized through anodic fluorination of alkynes having arylthio group and following Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) with benzyl azide. The other route toward the fluorinated triazoles, namely the anodic fluorination of triazole derivatives once prepared by advanced CuAAC of the alkyne and azide above was also investigated. Furthermore, Cu(I)-catalyzed isoxazole synthesis of fluorinated alkynes and imidoyl chloride was also successfully demonstrated. Figure 1

A new synthetic route to functionalized neutral and anionic azadiphospholes from easily accessible starting materials is described. Equimolar reaction of Na(OCP) and N-(2,6-dimethylphenyl)pivalimidoyl chloride 2 a cleanly affords the imidoxy-functionalized 1,2,4-azadiphosphole 3 a. Using Na(OCP) and imidoyl chloride in a 2:1 ratio leads to an anionic four-membered ring Na[4 a], which has been structurally characterized. During 16 h at room temperature, Na[4 a] rearranges to the anionic 1,3,4-azadiphospholide Na[5 a] with release of carbon monoxide. Applying the more sterically demanding N-(2,6-diisopropylphenyl)pivalimidoyl chloride allows isolation of the 1,3,4-azadiphospholide Na[5 b] in good yield (>70 %). Possible mechanisms leading to the new isomeric azadiphospholides have been investigated with the aid of high-level composite calculations.

The reactive imidoyl chloride adducts generated in situ from the reaction of isocyanide and acyl chlorides were trapped by 2-mercaptobenzimidazoles to yield highly functionalized dihydrobenzo[4,5]imidazo[2,1-b]thiazoles in good yields.

Neutral and cationic palladium(II) complexes containing three different heteroditopic bis(aryl)-substituted imino-N-heterocyclic carbene ligands have been synthesized and structurally characterized. Modifications made to the substituent at the iminic carbon allow for independent tuning of the steric and electronic environment around the metal center. The nature of this substituent profoundly affects the thermal stability of the neutral palladium complexes. While the tert-butyl derivative decomposes at 60 °C over a period of 24 h to give the corresponding 1-mesityl-2-methyl-1H-imidazole and the corresponding imidoyl chloride as the major products, the phenyl and methyl analogues show no sign of decomposition. Likewise, the corresponding cationic complexes of all three carbene derivatives are stable under the same conditions, with no evidence of decomposition. While inactive for ethylene polymerization, these palladium methyl complexes react with CO and isocyanides to form a variety of products, including s...

A highly efficient and convenient method was developed to synthesize 2,7-dimethyl-3- phenyl- quinazolin-4(3H)-ones from 2-acetamidobenzoic acid, arylamines, arylhydrazines and arylacylhydrazines. Quinazolin-4(3H)-ones were obtained in good to excellent yields (85–98%) using dropwise POCl3 as a condensing agent in acetonitrile. Theoretical calculations were performed to explore the competition reaction pathways and the corresponding free energy profiles for the reaction of 2-acetamido-4-methyl-benzoic acid with aniline. The calculations show that the reaction proceeds through three different stages, including the formation of benzoxazin-4-one, diamide and quinazolin-4(3H)-one. The formation of benzoxazin-4-one follows a Vilsmeier-Haack mechanism, in which the POCl3 transfers the 2-acetamido-benzoic acid into an imidoyl chloride, followed by intramolecular attack of the carboxyl oxygen involving addition-elimination sequence. The formation of diamide is initialized by the nucleophilic attack of the aniline nitrogen atom on the carbonyl carbon of benzoxazin-4-one, accompanied by aniline-assisted proton transferring. The formation of quinazolin-4(3H)-one follows an intramolecular nucleophilic addition-elimination mechanism, where the POCl3 helps the elimination of water. The present studies provide insight into the mechanism for the formation reactions of quinazolin-4(3H)-ones in the presence of POCl3.

Partially fluorinated triazole derivatives were synthesized through anodic fluorination of alkynes having arylthio group and following Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) with benzyl azide. The other route toward the fluorinated triazoles, namely the anodic fluorination of triazole derivatives once prepared by advanced CuAAC of the alkyne and azide above was also investigated. It was shown that these two routes are mutually complementary methodology for the synthesis of new mono- and difluoromethyltriazole derivatives. Furthermore, Cu(I)-catalyzed isoxazole synthesis from fluorinated alkynes and imidoyl chloride was demonstrated.

Seven novel glycosyl N-tosyl benzimidates were prepared by the reactions of the corresponding hemiacetals with imidoyl chloride in 55–88% yields, which were smoothly converted to glycosides, upon treatment with alcohols and catalytic TMSOTf, in 57–99% yields.

A simple one-pot and efficient method is described for the synthesis of pyrimido[5,4-c]pyridazines 5 and of thiino[2,3-d] pyrimidines 15 by a domino process involving an aza-Wittig reaction/heterocyclization. The iminophosphorane 2 reacted with phenylisocyanate, followed by heterocyclization on addition of amines to give the corresponding guanidine intermediates 4. The guanidine intermediates were cyclized in the presence of catalytic amount of sodium ethoxide to pyrimido[5,4-c]pyridazines 5. Similarly, iminophosphorane 12 reacted with phenylisocyanate and amines to give thiino[2,3-d]pyrimidines 15 in moderate yields. Furthermore, pyridazino[4,3-d]oxazines 10 and thiino[2,3-d]oxazines 19 were synthesized by the intremolecular aza-Wittig reaction of phosphazenes 2 and 12, respectively, with acid chlorides followed by heterocylization via imidoyl chloride intermediates. J. Heterocyclic Chem., (2012).

N-Phenyltrifluoroacetimidoyl chloride (PTFAI-Cl) is a reagent widely used for the preparation of glycosyl N-phenyltrifluoroacetimidates. However, the most commonly applied method requires carbon tetrachloride, a hepatotoxic reagent that has been phased out under the Montreal Protocol. We report a new synthesis of N-phenyltrifluoroacetimidoyl chloride (PTFAI-Cl) using dichlorotriphenylphosphane and triethylamine.

We herein report a simple and convenient one-pot synthesis of highly substituted 2-imidazolines in a regiocontrolled and stereospecific matter through the ring expansion reaction of an imidoyl chloride with an aziridine, analogous to the Heine reaction.

Pyrrol-1-ines obtained by 1,3-dipolar cycloaddition of nitriles ylides to gem-disubstituted by withdrawing groups olefins are converted to 1-pyrrolinium salts by methylfluorosulfonate. Nucleophilic addition to these iminium salts affords 1 -pyrrolidines in good yields. Attempts to synthesize aziridines by thermolysis or flash thermolysis of these pyrrolidines through cycloreversion was unsuccessful. However the fragmentation under electronic impact of the pyrrolidines obtained from imidoyl chloride 5A and 5B allowed us to establish the 5 position of the paranitrophenyl group in the pyrrol-1-ine cycloadducts.

1,6-Dioxa-6aλ4-thia-3,4-diazapentalenes 7 and 1,3,4,6-tetraaza-6aλ4-thiapentalenes 15, two new classes of compounds with single bond-no bond resonance, have been prepared by reaction of 5-amino-1,2,3,4-thiatriazole 4 with acyl chlorides and imidoyl chlorides. In the latter case, the salts of 5-imino-Δ3-1,2,4-thiadiazolines 12 were first isolated and subsequently reacted with a second equivalent of imidoyl chloride. This also led to the synthesis of unsymmetrically substituted 1,3,4,6-tetraaza-6aλ4-thiapentalenes. In the presence of bases, the salts 12 decompose via the isolable free bases 13 into N-cyanoamidines 14 and sulfur. Treatment of the dioxathiapentalenes 7 with P4S10, or direct thiobenzoylation of 4 gave the 3,4-diaza-1,6aλ4-trithiapentalenes 9.

A series of thienopyrimidines and related heterocycles were synthesized by refluxing related imidoyl chloride with primary and secondary amines under microwave irradiation and classical heating. The imidoyl chlorides were synthesized from corresponding cyclic imides with phosphorus oxychlorides under microwave irradiation and classical heating. The structures of the compounds were confirmed by FT-IR, NMR. The synthesized compounds were screened for anti psychotic activity.

Pyrazino[2′,3′:4,5]thieno[3,2- D]pyrimidine derivatives 6 were synthesized by the intermolecular aza-Wittig reaction of N-heteroaryl phosphazene derivatives with carboxylic acid chlorides. The heterocyclization occurs via imidoyl chloride intermediates derived from phosphazenes 4A, B, obtained in a one-step process from α-azidothieno[2,3- B]pyrazine carboxylic acid 3. Moreover, cyclic pyrazinothienopyrimidines were prepared, in a two-step procedure, from amides and azidothienopyrazine-α-carbonyl chloride using an intramolecular aza-Wittig heterocyclization reaction strategy.

Dehydrogenative cyclization of the 6-substituted 7-arylidenehydrazinotetrazolo[1,5-b][1,2,4]triazines derived from 6-methyl and 6-phenyl derivatives of 7-hydrazinotetrazolo[1,5-b][1,2,4]triazines and aromatic aldehydes gave the corresponding 6-substituted 9-aryl-[1,2,4]triazolo[4,3-d]tetrazolo-[1,5-b][1,2,4]triazines. The latter compounds were also obtained by an alternative route involving dehydrative cyclization of 6-methyl and 6-phenyl derivatives of 7-chlorotetrazolo[1,5-b][1,2,4]triazines with aromatic hydrazides through the isolable aroylhydrazino intermediates. Also, the triazolotetrazolotriazine rings were accomplished by one-pot cyclization of cyclic amidrazones with aromatic acid chlorides. The ditetrazolo[1,5-b:1′,5′-d][1,2,4]triazine systems were synthesized by cyclization of the former cyclic amidrazones with nitrous acid, or cyclic imidoyl chlorides with sodium azide. The bis-triazolotetrazolotriazine derivatives were synthesized by cyclization of two equivalents of each cyclic imidoyl chloride with acid dihydrazides through the isolable bis-hydrazide products. The antimicrobial activity of representative compounds was studied.

Fluorinated N-[2-(haloalkyl)phenyl]imidoyl chloride, which was readily available from the corresponding anilines by using Uneyama's one-pot synthesis of fluorinated imidoyl chloride, was found to be a key intermediate for the facile synthesis of 2-fluoroalkyl substituted indole derivatives via the Grignard cyclization process. The bromination of 3-methyl group of 3-methyl-2-trifluoromethyl indole with NBS/CCl4 led to the formation of 3-bromomethyl substituted indole which can be further utilized to synthesize some new and biologically interested indole derivatives.

Methods for the preparation of heterocyclic systems, the chemical transformations of heterocyclic compounds under conditions of phase-transfer catalysis, and the use of quaternized heterocycles as phase-transfer catalysts are considered.

Polyfluoroalkylated aldimines were prepared by reducing polyfluoroalkyl imidoyl chlorides, which are readily available from polyfluoroalkanoic acids, with LTBA (lithium tri- TERT-butoxyaluminum hydride).

A preparative method for the synthesis of novel N-phosphorylcarbonyl-and N-alkoxycarbonyltrichloroacetimidoylphosphonates from accessible pentachloroethyl isocyanate was developed. Factors that determine the C/N-selectivity of the phosphorylation of trichloroacetimidoyl chlorides were revealed: phenyl substituents at the P atom and an electron-withdrawing N-alkoxycarbonyl group in imidoyl chloride favored N-phosphorylation, while reactions with silyl phosphite gave exclusively C-phosphorylation products.

The synthesis of a series of rod-coil diblock copolymers with flexible poly(ethylene oxide) chains (M n = 5 000 g mol -1 ) and rod blocks consisting of monodisperse oligo(p-benzamide)s is described. The formation of defined supramolecular aggregates in solution as well as the solid state has been analyzed. The length of the oligo(p-benzamide)s has been systematically varied from n = 1 to 7 units. The influence of n on aggregation in chloroform and aqueous solution was investigated by GPC as well as UV-vis spectroscopy. A critical aggregation length was found for chloroform (n = 5) and water (n = 4), below which no aggregation is observed under otherwise identical experimental conditions. Aggregation of the polymers in chloroform solution can be chemically reversed by the addition of PCl 5 , resulting in conversion of the aromatic amides into imidoyl chlorides. Such amide-protected block copolymers show no aggregation in NMR and GPC experiments. Imidoyl chloride formation was shown to be reversible, i.e., addition of water regenerated the oligo(p-benzamide) blocks.

By modification of the known literature procedures, the key intermediate product – Nphenyl(phenylimino)methylchloromethanimidoyl chloride 3 was prepared. Nucleophilic substitution reactions of the prepared imidoyl chloride with various secondary amines gave the corresponding intermediates, very useful for the syntheses of corresponding imidoyl isothiocyanates 5a-e. The subsequent cyclization reaction of these isothiocyanates afforded novel substituted 1,3,5-benzotriazocine derivatives 6a-e .