Imidoyl Chlorides Research Articles

Facile synthesis of alpha-fluoro, substituted amidines from imidoyl chlorides and some of its application amidines; fluorinated benzoimidazole; aryl amination; 1,4-dihydropyridine; fluorinated aminals

A series of a-fluoro subustituted amidines were synthesized from corresponding fluorinated imidoyl chlorides in good to excellent yields and some of its applications are outlined in our programs. (c) 2006 Elsevier B.V. All rights reserved.

Synthesis of polyamidines based on aromatic bis(imidoyl) chlorides in solution

New amidine-containing polymers were prepared by the polycondensation of aromatic diamines with bis(imidoyl) chlorides in polar organic solvents in the presence of various catalysts (triethylamine, tributylamine, and pyridine N-oxide). Optimal synthesis conditions, namely, temperature, duration, concentration of monomers and catalyst, and the order of reagent loading, were established. The structure of polyamidines was studied by elemental analysis and IR and NMR spectroscopy. When the polymers were heated to 250°C in vacuum, their molecular masses increased.

Novel C-phosphorylated heterodienes based on pentachloroethyl isocyanate

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.

Rod‐Length Dependent Aggregation in a Series of Oligo(p‐benzamide)‐Block‐Poly(ethylene glycol) Rod‐Coil Copolymers

AbstractSummary: The synthesis of a series of rod‐coil diblock copolymers with flexible poly(ethylene oxide) chains ($\overline M _{\rm n}$ = 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 PCl5, 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.Conversion of aramide block copolymer into molecularly dissolved form using PCl5.magnified imageConversion of aramide block copolymer into molecularly dissolved form using PCl5.

Palladium‐Catalyzed Synthesis of α‐Iminoamides (IV), (VII) and (X) from Imidoyl Chlorides and a Carbamoylsilane.

ChemInformVolume 36, Issue 45 Isocyclic Compounds Palladium-Catalyzed Synthesis of α-Iminoamides (IV), (VII) and (X) from Imidoyl Chlorides and a Carbamoylsilane. Robert F. Cunico, Robert F. Cunico Dep. Chem. Biochem., North. Ill. Univ., DeKalb, IL 60115, USASearch for more papers by this authorRajesh K. Pandey, Rajesh K. Pandey Dep. Chem. Biochem., North. Ill. Univ., DeKalb, IL 60115, USASearch for more papers by this author Robert F. Cunico, Robert F. Cunico Dep. Chem. Biochem., North. Ill. Univ., DeKalb, IL 60115, USASearch for more papers by this authorRajesh K. Pandey, Rajesh K. Pandey Dep. Chem. Biochem., North. Ill. Univ., DeKalb, IL 60115, USASearch for more papers by this author First published: 11 October 2005 https://doi.org/10.1002/chin.200545101Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume36, Issue45November 8, 2005 RelatedInformation

Palladium-Catalyzed Synthesis of α-Iminoamides from Imidoyl Chlorides and a Carbamoylsilane

A series of pure imidoyl chlorides were converted into alpha-iminoamides by treatment with a carbamoylsilane under catalysis by palladium(0) complexes.

Reactions of 1,4‐Benzodiazepinic N‐Nitrosoamidines with Tosylmethyl Isocyanide: A Novel Synthesis of Midazolam.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Soluble Oligoaramide Precursors—A Novel Class of Building Blocks for Rod–Coil Architectures

A new synthetic route is described that allows the reversible conversion of the inherently insoluble oligo-p-benzamides into soluble materials through the formation of imidoyl chlorides. Syntheses of the corresponding dimer, trimer, and tetramer are reported; these compounds can easily be purified by crystallization and are accessible on the multigram scale. Structural proof was obtained by single-crystal X-ray structures of the trimer and tetramer precursors. They can be selectively functionalized into amides or esters at the terminal carboxylic acid group followed by hydrolysis of the imidoyl chlorides to the parent amides. This new class of compounds gives access to strongly aggregating rigid rodlike materials in few synthetic steps, as is demonstrated by the preparation of poly(ethylene glycol)-co-oligo(p-benzamide) rod-coil block copolymers.

Imidoyl isothiocyanates in the synthesis of condensed heterocycles: Preparation of some substituted benzotriazocines

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 .

Convenient synthesis of 2-alkylamino-6-carboxy-5,7-diarylcyclopenteno[1,2- b]pyridines via direct acylamination with imidoyl chlorides

A robust synthetic method for 2-alkylamino-6-carboxy-5,7-diarylcyclopenteno[1,2- b]pyridines via acylamination at the alpha position of the functionalized pyridine system has been developed. The key step in this method was achieved by treatment of the corresponding pyridine N-oxides with 2.5 equiv of imidoyl chlorides in the presence of triethylamine, thus producing the desired 2-acylaminopyridines in good yields (74–96%).

Sigmatropic isomerizations in azaallyl systems: XXI. Alkanimidoylphosphonates and their prototropic and phosphorotropic isomers

Synthetic procedures for alkanimidoylphosphoryl derivatives with α-hydrogen atoms in the N-alkyl radical are developed. Data on the effect of substituents at the carbon and phosphorus atoms on the facility of prototropic transitions in the C=N-C triad are summarized. The most facile proton transfer occurs in the N-benzyl derivatives, and the prototropic isomer is the more stable, the stronger the electron-acceptor power of the substituent at the sp3-carbon atom of the azaallyl triad. The proton transfer in N-(α-phenethyl)-trifluoroacetimidoylphosphonates proceeds selectively, which allows preparation of enantiomerically enriched derivatives of α-aminotrifluoroethylphosphonic acid. A specific effect of substituents at the phosphorus atom on the prototropism attendant on phosphorylation of imidoyl chlorides is demonstrated.

Nitrile ylide dimerization: investigation of the carbene reactivity of nitrile ylides.

A series of novel hexaaryl diazatrienes 5 ("nitrile ylide dimers") were synthesized directly from the corresponding diaryl ketimines 12 and dichlorotoluenes 13 in a facile one-pot synthesis. The carbene character of the nitrile ylides was investigated by varying the substituents on the aromatic ring adjacent to the carbene center. The isolation of the corresponding carbene dimers as stable crystalline materials with absorption maxima (lambda(max)) from 363 to 422 nm was shown to be promoted by the absence of strongly electron-withdrawing substituents. The crystal structures indicate that the E-isomers were isolated when phenyl, 3-methylphenyl, and 3-chlorophenyl substituents are present at the carbene carbon; the Z-isomer was isolated when the more sterically hindered 2,4,6-trimethylphenyl substituent (Mes) is present. The (1)H NMR spectra of the E-isomers demonstrate the nonequivalence of the aromatic rings, in which two of the aromatic rings of the imine moiety are pseudoaxial and the remaining aromatic rings are pseudoequatorial. The reactions proceed via the intermediate nitrile ylides 1 generated by the base-promoted 1,1-elimination of HCl from the intermediate chloroimine 14. The nitrile ylide was also generated by 1,3-elimination of HCl from the imidoyl chloride 18, confirming common pathways via the nitrile ylide as the dimer products obtained from these different routes were identical. The strongly electron-withdrawing 4-nitrophenyl substituent promotes the linear carbanion character of the 1,3-dipole and no dimer is formed.

Derivatives from Isoselenocyanates: Synthesis of 2‐Phenyl‐6H‐[5,1,3]benzoselenadiazocine

AbstractThe reaction of N‐phenylbenzimidoyl isoselenocyanates 8 with primary and secondary amines in acetone at room temperature, followed by treatment with a base, led to 6H‐[5,1,3]benzoselenadiazocine derivatives of type 10 (Scheme 3). An analogous cyclization was observed when 8a and 8b were reacted with the Na salt of diethyl malonate in EtOH at room temperature, which yielded the eight‐membered selenaheterocycles 11 (Scheme 5). The molecular structures of some of the products, as well as that of a sulfur analogue, have been established by X‐ray crystallography (Figs. 1–4). The isoselenocyanates 8 have been prepared from N‐(2‐methylphenyl)benzamides 5 in a three‐step procedure via the corresponding imidoyl chlorides 6, side‐chain chlorination to give 7, and treatment with KSeCN (Scheme 2).

Iminohydroxamato Early and Late Transition Metal Halide Complexes − New Precatalysts for Aluminoxane‐Cocatalyzed Olefin Insertion Polymerization

AbstractWe report on new families of non‐metallocene metal precatalysts for olefin polymerization with titanium, zirconium, vanadium and nickel as the active metal sites. The novel ligand design concept is based on iminohydroxamic acids and their derivatives as the principal chelating units. Various anionic and neutral [N,O] and [N,N] ligand systems are easily accessible by a modular synthetic sequence of imidoyl chlorides with substituted hydroxylamines or hydrazines, respectively. Steric protection of the metal coordination site, a necessary requirement for suppression of chain termination pathways of non‐metallocene catalysts, is brought about by bulky aryl substituents on the imino nitrogen atoms. Crystal structures of some of the hydroxamato ligands reveal interesting intermolecular hydrogen‐bridged structures, whereas in the solid‐state structure of one titanium precatalyst a five‐membered chelate was observed, in line with the design principle of these systems. Preliminary ethylene polymerization studies with methylaluminoxane‐activated metal complexes (M = Ti, Zr, V, Ni) show that the most active systems are [N,O]NiBr2 catalysts containing neutral O‐alkyl iminohydroxamate ligands. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Reactions of 1,4-BenzodiazepinicN-Nitrosoamidines with Tosylmethyl Isocyanide: A Novel Synthesis of Midazolam

Reaction of 1,4-benzodiazepinic N-nitrosoamidines, used as synthetic equivalents of imidoyl chlorides, with the monoanion of tosylmethyl isocyanide is described. The process gives entry to 3-(4-tosyl)imidazo[1,5-a][1,4]benzodiazepines, compounds which have not been described yet in the literature. These systems can be derivatized to the corresponding trisubstituted 1,4-benzodiazepines by alkylation or acylation of the imidazole ring. These new heterocyclic derivatives are potentially useful in the field of medicinal chemistry. In addition, midazolam 3, the anesthetic properties of which are well established, can be easily prepared in one step by desulfonylation of compound 7a.

Novel Approach for Asymmetric Synthesis of Fluorinated β‐Amino Sulfones and Allylic Amines.

AbstractFor Abstract see ChemInform Abstract in Full Text.

N‐(Arylsulfonyl)trihaloacetimidoyl Chlorides and Their Reactions with Phosphites

AbstractWe have developed a convenient synthetic approach to highly reactive N‐(arylsulfonyl)trichloro‐ and ‐trifluoroacetimidoyl chlorides 2 by reacting the corresponding N‐acylsulfonamides with PCl5. The interaction of the imidoyl chlorides with phosphites proceeds through different pathways depending on the substituents in the reagents, and leads to N‐arylsulfonyl‐N‐trichlorovinylphosphoramidates 4, 1‐arylsulfonylamino‐1‐chlorotrifluoroethylphosphonate 5, C,N‐bis(phosphorylated) N‐dihalovinylsulfonamides 8 and α‐(arylsulfonylamino)trifluoroethylidenebis(phosphonates) 10. A rare example of an aza‐Perkow reaction involving a trifluoromethyl group was discovered. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Efficient synthesis of 2-alkylidene-3-iminoindoles, indolo[1,2-b]isoquinolin-5-ones, delta-carbolines, and indirubines by domino and sequential reactions of functionalized nitriles.

The sodium hydride mediated cyclization of arylacetonitriles with oxalic acid bis(imidoyl) dichlorides, aza-analogues of oxalyl chloride, afforded functionalized 2-alkylidene-3-iminoindoles with very good regio- and E/Z selectivity. Excellent chemoselectivities were observed for functionalized substrates. Based on these results a domino "cyclization-lactamization" reaction of bis(imidoyl) chlorides with methyl 2-(cyanomethyl)benzoate was developed. This process allowed a convenient one-pot synthesis of indolo[1,2-b]isoquinolin-5-ones related to tryptanthrin. A new and convenient synthesis of delta-carbolines by intramolecular electrocyclization-elimination reactions of 2-alkylidene-3-iminoindoles was developed. It was shown that delta-carbolines selectively bind to triplex or duplex DNA (intercalation). Indirubine analogues were prepared by deprotection and lactonization of functionalized 2-alkylidene-3-iminoindoles.

New Synthesis of 1,3‐Dihydro‐1,4‐benzodiazepin‐2(2H)‐ones and 3‐Amino‐1,3‐dihydro‐1,4‐benzodiazepin‐2(2H)‐ones: Pd‐Catalyzed Cross‐Coupling of Imidoyl Chlorides with Organoboronic Acids.

A new approach to the synthesis of 1,4-benzodiazepines and 3-amino-1,4-benzodiazepines, which employs the Pd-catalyzed cross-coupling reaction of an imidoyl chloride with an organometallic reagent as the key step, is described. A five-step synthesis of a key intermediate is described and it is shown that in only four further steps (three couplings and a TFA-mediated BOC-deprotection) a wide variety of N1-, C3-amino-, C5-carbon-, or nitrogen-substituted 1,4-benzodiazepines can be synthesized.

Novel approach for asymmetric synthesis of fluorinated beta-amino sulfones and allylic amines.

[reaction: see text] Enantiomerically pure gamma-fluoroalkyl beta-amino sulfones are readily synthesized in three steps starting from fluorinated imidoyl chlorides and arylmethyl sulfones. A complementary two-step sequence starting from chiral fluorinated beta-amino sulfoxides has also been developed. To illustrate the application of this procedure, a new method for the synthesis of alpha-fluoroalkyl allylic amines in optically pure form involving a Julia methylenation-desulfonylation reaction is presented.