Synthesis and reaction of 2-imino-1,3-thiazetidines and 2-imino-1,3-dithietanes

2-Imino-1,3-thiazetidines and 2-imino-1,3-dithietanes were synthesized and their reactivities were studied. The former readily underwent ring-opening reaction with amines to yield guanidine derivatives. The reaction products were applied to the synthesis of heterocycles such as triazoles and triazines. The latter was converted to isothiocyanate by the reaction of m-chloroperbenzoic acid.     

A novel entry toward 2-imino-1,3-thiazolidines and 2-imino-1,3-thiazolines by ring transformation of 2-(thiocyanomethyl)aziridines

A new, efficient, and straightforward synthesis of 3-arylmethyl-4-chloromethyl-2-imino-1,3-thiazolidines and 2-(N-acylimino)-3-arylmethyl-4-chloromethyl-1,3-thiazolidines has been developed by ring transformation of 1-arylmethyl-2-(thiocyanomethyl)aziridines upon treatment with a catalytic amount of titanium(IV) chloride in dichloromethane. The latter 2-(thiocyanomethyl)aziridines were prepared in high yields from 1-arylmethyl-2-(bromomethyl)aziridines by reaction with potassium thiocyanate in DMF. The 2-imino-1,3-thiazolidines and 2-(N-acylimino)-1,3-thiazolidines thus obtained can be easily interconverted, either by treatment with an acid chloride and a base in ether toward 2-(N-acylimino)thiazolidines or by treatment with potassium carbonate in methanol toward N-deprotected 2-iminothiazolidines. Dehydrohalogenation of 2-(N-acylimino)-3-arylmethyl-4-chloromethyl-1,3-thiazolidines by means of potassium tert-butoxide in DMSO afforded 2-(N-acylimino)-4-methyl-2,3-dihydro-1,3-thiazolines in good yields.     

Regiospecific iodocyclization of S-allyl dithiocarbamates: synthesis of 2-imino-1,3-dithiolane and 2-iminium-1,3-dithiolane derivatives

4-Alkyl-2-imino-1,3-dithiolanes and 4-alkyl-2-iminium-1,3-dithiolanes were prepared in excellent yields with complete regiospecificity under mild conditions by the iodocyclization of S-allyl dithiocarbamates. Dehydrohalogenation of the 4-alkyl-2-imino-1,3-dithiolanes gave 4-alkylidene-2-imino-1,3-dithiolanes in excellent yields.     

Ring-chain transformations of substituted 2-imino-1,3-thiazinoazoles

The ring-chain transformations of substituted 2-imino-1,3-thiazinoazoles in DMSO under the influence of tetraalkylammonium or alkali metal hydroxides were studied by acid-base potentiometric titration and PMR, IR, and UV spectroscopy.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 992–994, July, 1988.     

Selective synthesis of novel 2-imino-1,3-selenazolidin-4-ones and 2-amino-1,3,4-selenadiazin-5-ones from isoselenocyanates

An efficient and regioselective synthesis of 2-imino-1,3-selenazolidin-4-ones and 2-amino-1,3,4-selenadiazin-5-ones was achieved via one-pot reaction of isoselenocyanates, hydrazines, and ethyl chloroacetate or chloroacetyl chloride, respectively. Plausible mechanisms for these transformations were given.     

Five-membered 2,3-dioxo heterocycles: LXXV. Reaction of methyl 1-aryl-3-aroyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates with 1,3-diphenylguanidine. Crystalline and molecular structure of 9-Benzoyl-8-hydroxy-2-imino-6-(4-methylphenyl)-1,3-diphenyl-1,3,6-triazaspiro-[4.4]non-8-ene-4,7-dione

Methyl 1-aryl-3-aroyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with 1,3-diphenylguanidine to give the corresponding 6-aryl-9-aroyl-8-hydroxy-2-imino-1,3-diphenyl-1,3,6-triazaspiro[4.4]non-8-ene-4,7-diones. The molecular and crystalline structures of 9-benzoyl-8-hydroxy-2-imino-6-(4-methylphenyl)-1,3-diphenyl-1,3,6-triazaspiro[4.4]non-8-ene-4,7-dione were determined by X-ray analysis.     

Solid-phase synthesis of tetrasubstituted 2-imino-1,3-thiazolines using a functionalizing cleavage strategy

A novel solid-phase synthesis of tetrasubstituted 2-imino-1,3-thiazolines using a functionalizing cleavage strategy is described. The synthetic route utilized the ambident reactivity of a dithiocarbamate functionality to synthesize the key resin-bound electrophilic thiazolium intermediate. The desired products were efficiently obtained in high purity by the reaction of various amines with the thiazolium salt.     

Synthesis of 6-imino-5-tetrahydro-1H-2-pyrrolylidenhexahydro-2,4-pyrimidinediones as intermediates for the synthesis of C-azanucleosides

The method for the synthesis of 6-imino-5-tetrahydro-1H-2-pyrrolylidenhexahydro-2,4-pyrimidinediones is described. It is shown that the reaction of phosphorus trichloride, 2-pyrrolidones and 6-aminopyrimidines brings to condensation producing 6-imino-5-tetrahydro-1H-2-pyrrolylidenhexahydro-2,4-pyrimidinediones as intermediates for the synthesis of C-azanucleosides. The reaction of 6-imino-1,3-dimethyl-5-tetrahydro-2-pyrrolylidenhexahydro-2,4-pyrimidinedione with benzoyl chloride produces 10-benzoyl-2,4-dimethyl-6-phenyl-1,2,3,4,8,9-hexahydropyrimido[5,4-e]pyrrolo[1,2-c]pyrimidine-1,3-dione. A method for the selective reduction of the carbomethoxy group of methyl 5-(4-imino-1,3-dimethyl-2,6-dioxohexahydro-5-pyrimidinyliden)-2-pyrrolidine carboxylate by system NaBH₄/1,4dioxane/CoCl₂/PEG-400 is described.     

Formation of Fluoroderivatives of 1,2,3,4-Tetrahydro-1,3-diazafluorene from 2-Dialkylamino- 3-(1-imino-2,2,2-trifluoroethyl)hexafluoroindenes

2-Dimethylamino-3-(1-imino-2,2,2-trifluoroethyl)hexafluoroindene in the presence of DMSO or NEt₃ undergoes isomerization into 1-methyl-4-trifluoromethyl-5,6,7,8,9,9-hexafluoro-1,2,3,4-tetrahydro-1,3-diazafluorene, and from 1-(1-amino-2,2,2-trifluoroethylidene)octafluoroindane by the treatment with water solution of NHEt₂ 2-methyl-4-trifluoromethyl-1-ethyl-5,6,7,8,9,9-hexafluoro-1,2,3,4-tetrahydro-1,3-diazafluorene was obtained.     

The reaction of 1,3-dibutyl-2-ethoxy-4,5-dimethyl-2-oxo-1,3,2-diazaphosphol-4-ene with tetracyanoethylene

The reaction of 1,3-dibutyl-2-ethoxy-4,5-dimethyl-2-oxo-1,3,2-diazaphosphol-4-ene with tetracyanoethylene gives 6-amino-1,3-dibutyl-5-cyano-2-ethoxy-4-(1-imino-2-cyanoethyl)-2-oxo-1,3,2-diazaphosphindane.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 303–305, February, 1994.     

Efficient method for the synthesis of 1,3-unsubstituted 2-imino-5-oxooctahydroimidazo[4,5-d]imidazolium iodides based on thioglycolurils

Chemistry of Heterocyclic Compounds - A facile and efficient two-step synthetic route to previously inaccessible 1,3-unsubstituted 2-imino-5-oxooctahydroimidazo[4,5-d]-imidazol-1-ium iodides has...     

Domino reactions of 1,2-diimidoyl-1,2-dichloroethanes. Synthesis of 3-imino-1,2-dithia-3h-cyclopent-4-enes, 3-amino-2-thioxo-2,5H-pyrrol-5-ones, 2,3-diamino-4-thioxo-4H-thiopyrans, and 6-imino-6H-1,3-oxazines

The reaction of mono- and dilithiated ethyl thioglycolate with 1,2-diimidoyl-1,2-dichloroethanes, aza-analogues of oxalyl chloride, afforded (depending on the reaction conditions) 3-imino-1,2-dithia-3H-cyclopent-4-enes, 3-amino-2-thioxo-2,5H-pyrrol-5-ones, and 2,3-diamino-4-thioxo-4H-thiopyrans. The reaction of the dianion of ethyl hippurate with 1,2-diimidoyl-1,2-dichloroethanes afforded 6-imino-6H-1,3-oxazines.     

IR spectra and structure of 2- imino-1,3-dimethylbenzimidazolines

The fine structure of some N-substituted 2-imino-1,3-dimethyl-benzimidazolines is examined with the aid of IR spectroscopy. It is shown that the introduction of an alkyl or phenyl group into the imino group does not affect the C=N group or the imidazoline ring structure. In salts of 2-imino-1,3-dimethylbenzimidazoline and its N-substituted derivatives, the heterocyclic system has the benzimidazolium structure. The structure of 2-imino-1,3-dimethylbenzimidazolines in which the exocyclic nitrogen atom has electrophilic substituents which are conjugated with the heterocycle is characterized by a considerable contribution from dipolar forms, with the imidazole ring bearing a positive charge.Translated from Khimiya Geterotskilicheskikh Soedinenii, Vol. 6, No. 5, pp. 674–678, May 1970.     

Condensed 1,3-benzothiazinones. 1. Facile synthesis of 2-amino-1,2,4-triazolo[5,1-b][1,3]-benzothiazin-9-one

Treating 2-mercaptobenzohydrazide ( 1a ) with cyanogen bromide gave 3-amino-2-imino-3,4-dihydro-2.H-1,3-benzothiazin-4-one ( 2a ). This compound underwent further cyclocondensation with a second molecule of cyanogen bromide or S-methylisothiourea sulfate to afford the biologically interesting 2-amino-1,2,4-triazolo-[5,1-b][1,3]benzothiazin-9-one ( 3c ). Compound 3c could also be prepared directly from 1a by treating with excess amount of cyanogen bromide in more satisfactory yield.     

Synthesen von Heterocyclen, 63. Mitt.: Über 4-Hydroxy-6-imino-1,3-oxazine

Zusammenfassung Bei der Kondensation von Benzamid mit Cyanessigsäure in Acetanhydrid bei Temperaturen um 100° entsteht 4-Hydroxy-6-imino-1,3-oxazin (I). Es können auch Derivate des Benzamids und monosubstituierte Cyanessigsäuren eingesetzt werden.

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The condensation reaction between benzamide and cyanoacetic acid in acetic anhydride at temperatures of about 100° leads to the formation of 4-hydroxy-6-imino-1,3-oxazine (I). Derivatives of benzamide and monosubstituted cyanoacetic acids are also suitable reactants.

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J. R. Geigy AG, Basel, schweiz. Prior. vom 24. 6. 1960.     

5-Mercapto derivatives of 1,3-dimethylbenzimidazoline

The preparation of tin and sodium 1,3-dimethylbenzimidazolone-and 2-imino-1,3-dimethylbenzimidazoline-5-thiolates and their S-methyl and S-benzoyl derivatives is described. The hydrolysis of sodium 2-imino-1,3-dimethylbenzimidazoline-5-thiolate forms the fairly stable thiol.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 8, pp. 1127–1128, August, 1970.     

Synthesis, Characterization, and Antibacterial Activity of Complexes of (1S,2S)-N,N-1,2-Diphenylethylene-bis-(5-imino-1-phenyl-1,3-hexanedione)

Summary.  The synthesis and characterization of homobimetallic complexes of VO(IV), Cr(II), Co(II), Ni(II), and Cu(II) with the chiral Schiff base (1S,2S)-N,N-1,2-Diphenylethylene-bis-(5-imino-1-phenyl-1,3-hexa-nedione) is reported. The metal ions occupy both compartments of the ligand; water molecules fill the coordination spheres to provide an octahedral environment around the central atoms. The antibacterial activity of both mono- and bimetallic complexes against a number of Gram-positive as well as Gram-negative bacteria has been tested and is discussed. Received March 28, 2000. Accepted May 26, 2000     

Synthesis, Characterization, and Antibacterial Activity of Complexes of (1S,2S)-N,N-1,2-Diphenylethylene- bis -(5-imino-1-phenyl-1,3-hexanedione)

 The synthesis and characterization of homobimetallic complexes of VO(IV), Cr(II), Co(II), Ni(II), and Cu(II) with the chiral Schiff base (1S,2S)-N,N-1,2-Diphenylethylene-bis-(5-imino-1-phenyl-1,3-hexa-nedione) is reported. The metal ions occupy both compartments of the ligand; water molecules fill the coordination spheres to provide an octahedral environment around the central atoms. The antibacterial activity of both mono- and bimetallic complexes against a number of Gram-positive as well as Gram-negative bacteria has been tested and is discussed.     

Reaction of 2-amino-4-imino-2-perfluoropentene with ethylenediamine and diethylenetriamine

The transamination of 2-amino-4-imino-2-perfluoropentene with ethylenediamine gives the corresponding 6-fluoro-5,7-bis(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepine. The transamination of 2-amino-4-imino-2-perfluoropentene by diethylenetriamine is accompanied by intramolecular nucleophilic substitution of the α-fluorine atom to form 1,9-bis(trifluoromethyl)-3,4,6,7-tetrahydro-2H-pyrazino[1,2-a]pyrazine whose structure was established by an X-ray structural investigation. Several salts of this bicyclic compound and its complex with BF₃ have been described. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1773–1776, October, 1993.