Synthesis and properties of water-soluble 2-aminomethylidene derivatives of 1,3-dicarbonyl compounds

A series of [(2-dimethylamino)ethylamino]methylidene-1,3-dicarbonyl compounds was synthesized for the first time starting from the corresponding 2-ethoxymethylidene derivatives and N,N-dimethylethylenediamine. It was shown that further alkylation of aminomethylidene derivatives with methyl iodide occurs regioselectively at the tertiary nitrogen atom. Quaternization products obtained exhibit high corrosion inhibition of mild steel in hydrochloric acid medium.     

New tetradentate N2O2-ligands based on 2-ethoxymethylidene-3-oxo-3-polyfluoroalkylpropionates and ethylenediamine

Condensation of ethylenediamine at the ethoxymethylidene substituent of ethyl 2-ethoxymethylidene-3-oxo-3-polyfluoroalkylpropionates gave diethyl N,N′-ethylenebis(2-aminomethylidene-3-oxo-3-polyfluoroalkylpropionates) as new tetradentate N₂O₂-ligands which were used to obtain the corresponding metal complexes.     

Facile synthesis of 6-organyl-4-(trifluoromethyl)pyridin-2(1H)-ones and their polyfluoroalkyl-containing analogs

The three-component cyclization of 3-polyfluoroalkyl-3-oxopropanoates and methyl ketones with ammonium acetate affords 6-organyl-4-(polyfluoroalkyl)pyridin-2(1H)-ones (organyl is alkyl, aryl, or hetaryl). The synthesized pyridones were evaluated for antifungal, antibacterial, and analgesic activity.

     

New enamine ligands derived from ethyl 2-ethoxymethylidene-3-oxo-3-polyfluoroalkylpropionates and <Emphasis Type="Italic">o</Emphasis>-phenylenediamine

Diethyl 2,2′ [1,2-phenylenebis(aminomethylidene)]bis(3-oxo-3-polyfluoroalkylpropionates) were synthesized by the condensation of a double excess of ethyl 2-ethoxymethylidene- 3-oxo-3-polyfluoroalkylpropionates with o-phenylenediamine. The use of equimolar ratios of the starting reactants affords ethyl 2-[(2-aminophenyl)aminomethylidene]-3-oxo- 3-polyfluoroalkylpropionates from which nonsymmetric biscondensation products were synthesized by the reaction with related reactants containing different polyfluoroalkyl substituent. The copper(II), nickel(II), and cobalt(II) complexes were obtained on the basis of new ligands.     

Perfluoroepoxyoxolanes in the synthesis of fluorine-containing heterocycles

Perfluoro-3,4-epoxyoxolane and 3,4-epoxy-2-trifluoromethylpentafluorooxolane readily reacted with difunctional nucleophiles via opening of the oxirane ring and subsequent heterocyclization. Their reactions with thiourea and o-phenylenediamine gave new fluorine-containing fused heterocyclic compounds, 2-amino-3a-hydroxy-4,4,6,6,6a-pentafluoro-3a,4,6,6a-tetrahydrofuro[3,4-d][1,3]thiazole and 1,1,3,3-tetrafluoro- and 1-trifluoromethyl-1,3,3-trifluoro-1,3-dihydrofuro[3,4-b]quinoxalines, respectively. The molecular and crystalline structures of the products were determined by X-ray analysis.     

Reaction of 1,1,2,3,3-pentafluoro-1,5-hexadiene with methanol in the presence of a base

The reaction of 1,1,2,3,3-pentafluoro-1,5-hexadiene (1) with MeOH in the presence of MeONa results in products of substitution, rearrangement, hydro-, or dehydrofluorination, depending on the reaction conditions.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 5–5, April, 1994.     

Isomerization of 1,1,2,3,3-pentafluoro-1,5-hexadiene upon reaction with fluoride ions. First example of sequential anionotropic and prototropic allylic rearrangements

Upon heating in DMF medium with KF and 18-crown-6 1,1,2,2,3-pentafluoro-1,5-hexadiene (1) is converted to 4,5,6,6,6-pentafluoro-1,3-hexadiene and 1,1,1,2,3-pentafluoro-2,4-hexadiene. Reaction of (1) with KHF₂ results in the formation of its HF addition product, namely, 4,4,5,6,6,6-hexafluoro-1-hexene. We assume that the driving force in the isomerization of (1) is the formation of conjugated products, involving both the fluorinated and nonfluorinated portions of the molecules, preferably with the minimum number of fluorine atoms attached to the double bond.Department of Fine Organic Synthesis, Institute of Organic Chemistry, Ural Branch, Russian Academy of Sciences, 620219 Sverdlovsk. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 408–411, February, 1992.     

Fluoroalkyl-containing β,β'-tricarbonyl compounds: Tautomerism and reaction with N-nucleophiles

The tautomeric composition of -polyfluoroacyl derivatives of acetylacetone and malonic ester has been established and it has been shown that with N-nu-cleophiles (ammonia, 1,2-ethylenediamine, o-phenylenediamine) these compounds undergo acid decomposition with the elimination of the polyfluoroacyl group. With hydrazines, malonic ester derivatives react similarly but acetylacetone derivatives undergo cyclization into pyrazoles. The regiodirectivity of the interaction of fluoroalkyl-containing ,-tricarbonyl compounds with N-nucleophiles does not depend on their tautomeric composition and is determined by orbital control.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 376–382, February, 1990.