Fluoroalkyl-substituted lithium 1,3-diketonates in reactions with hetarylhydrazines

Fluoroalkyl-substituted lithium 1,3-diketonates reacted with 4-hydrazinyl-6-methylpyrimidin-2-amine, 2,6-dimethylpyrimidin-4-ylhydrazine, 7-fluoroquinoxalin-6-ylhydrazine, and benzothiazol-2-ylhydrazine to give the corresponding hetaryl-substituted pyrazoles. The molecular and crystal structures of 4-methyl-6-(3-methyl-5-trifluoromethyl-1H-pyrazol-1-yl)pyrimidin-2-amine and 4-(5-difluoromethyl-4,5,6,7-tetrahydro-2H-indazol-2-yl)-6-methylpyrimidin-2-amine were determined by X-ray analysis.     

Synthesis and structure of fluoroalkyl containing lithium 1,3-diketonates

Russian Journal of General Chemistry - Methods of synthesis and IR, mass, NMR 1H, 19F, 13C spectra as well as X-ray analysis of fluoroalkyl containing lithium 1,3-diketonates are reviewed.     

Fluorinated lithium 1,3-diketonates as reagents to modify podands and crown-ethers

Fluorinated enaminoketones, a new type of ligands, bearing two independent coordination centers (polyether's and fluorinated enaminoketones fragments) have been obtained. The crystal structure of the Cu(II) complex of 1,5-bis-[2-(4′,4′,4′-trifluoro-1′-methyl-3′-oxo-but-1′-enylamino)-phenoxy]-3-oxapentane (10) has been elucidated by X-ray crystallography. The results obtained show that the complex 10 consists of two crystallographically independent molecules C₂₆H₂₄CuF₆N₂O₅ (A and B), and the metal atom in the complex 10 has four-coordinated arrangement, as a polyhedron with a distorted square with two nitrogen and two oxygen atoms located in corners.     

The transformations of fluoroalkyl-containing 2-arylhydrazono-1,3-dicarbonyl compounds with methylamine

Fluoroalkylated 1,2,3-triketone 2-arylhydrazones and 2-arylhydrazono-3-oxo esters react variously with methylamine depending on the structure of the fluorinated substituent. 2-Arylhydrazono-1,3-dicarbonyl compounds having “short” fluoroalkyl substituents condense with methylamine at the carbonyl group attached to the non-fluorinated substituent whereas ones containing a lengthy polyfluoroalkyl substituent undergo haloformic cleavage as a result of the amine addition at the carbonyl group bearing such a substituent. The resulting 2-arylazo-3-(N-methyl)amino-1-polyfluoroket-2-en-1-ones and 1-(N-methyl)amino-2-arylhydrazono-3-fluoroalkyl-3-oxopropanamides have complexing properties, and they can bind to nickel(II) and copper(II) ions. Nickel chelates can be obtained by a three-component condensation of 2-arylhydrazono-1,3-dicarbonyl compounds and methylamine in the presence of nickel(II) cations.     

Synthesis and structure of lithium 3-trifluoromethyl-1,3-diketonates containing pyridyl substituents

Russian Chemical Bulletin - Lithium 3-trifluoromethyl-1,3-diketonates containing pyridyl substituents were synthesized. The specific features of the crystal structures of lithium...     

Reaction of fluoroalkyl-containing 1,3-dicarbonyl compounds with benzylideneacetone

The reaction of fluoroalkyl-containing 1,3-dicarbonyl compounds with benzylideneacetone with the use of pyridine or triethylamine as a catalyst gave new 3-fluoroalkyl-4-ethoxycarbonyl(acyl)-5-phenylcyclohexan-3-ol-I-ones in yields of 16–33%. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 992–994, May, 1997.     

Reactions of fluoroalkyl-containing bis-β-diketones with hydrazine and hydroxylamine

Polyfluoroalkyl-containing bispyrazoles, bis(5-hydroxy-Δ²-isoxazolines), and bisisoxazoles were synthesized for the first time by reactions of polyfluoroalkyl-containing bis-β-diketones with hydrazine, phenylhydrazine, and hydroxylamine, respectively. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 762–764, April, 1999.     

Reactions of 2-arsa- and 2-stiba-1,3-dionato lithium complexes with group 4-7 metal halides

The reactions of a range of 2-arsa- and 2-stiba-1,3-dionato lithium complexes with group 4-7 metals have been investigated. These have given rise to several complexes in which an arsadionate acts as a chelating ligand; [V{η²-O,O-OC(Bu^t)AsC(Bu^t)O}₃], [M{η²-O,O-OC(Bu^t)AsC(Bu^t)O}₂(DME)], M=Cr or Mn; or as an η¹-As-diacylarsenide, [MnBr(CO)₄{As[C(O)Bu^t]₂Li(DME)}]₂. In addition, reactions of lithium arsadionates with TaCl₅ have led to metal mediated arsadionate decomposition reactions and arsadionate oxidative coupling reactions to give the known arsaalkyne tetramer, As₄C₄Bu^t₄, and the new tetraacyldiarsane, [{As[C(O)Mes]₂}₂] Mes=mesityl, respectively. The treatment of several lithium arsadionates with [MoBr₂(CO)₂(PPh₃)₂] has also initiated arsadionate decomposition reactions and the formation of the metal carboxylate complexes, [MoBr(CO)₂{η²-O₂C(R)}(PPh₃)₂] R=Bu^t, Ph, Mes. The X-ray crystal structures of six of the prepared complexes are discussed.     

Cyclization of fluoroalkyl-containing 1,3-dicarbonyl compounds with ethylenediamine hydroperchlorate to 1,4-diazepines

2,3-Dihydro-1H-1,4-diazepines and 1,2,3,4-tetrahydro-1,4-diazepin-5-ones were obtained by direct condensation of fluorine-containing 1,3-diketones and 1,3-keto ethers, respectively, with ethylenediamine monohydroperchlorate. The structure of the compounds was confirmed by¹H NMR, mass spectrometry and molecular weight determination.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 890–896, April, 1991.     

Synthesis and thermal properties of some lithium β-diketonates

Five new volatile lithium complexes were synthesized by reactions of lithium hydroxide monohydrate (LiOH · H₂O) with β-diketones, namely, dipivaloylmethane (HDpm), hexafluoroacetylacetone (HHfa), trifluoroacetylacetone (HTfa), benzoyltrifluoroacetone (HBtfa), pivaloyltrifluoroacetone (HPta), and valeryltrifluoroacetone (HVta). The complexes obtained were studied by IR and electronic absorption spectroscopy, mass spectrometry, and comprehensive thermal analysis. The temperature dependence of the vapor pressure, which was obtained by the Knudsen effusion method with mass-spectrometric analysis of the vapor phase composition in the 400–450 K range, was used to calculate the standard thermodynamic parameters of the Li(Dpm) sublimation: ΔH°_subl = 45.7 ± 1.7 kcal mol^?1 and ΔS°_subl = 77.9 ± 4.0 cal mol^?1 K^?1.     

Reaction of 2,3-epoxyoctafluorobutane with 2-aminobenzenethiol

The reaction of 2,3-epoxyoctafluorobutane with 2-aminobenzenethiol in N,N-dimethylacetamide gave 3-(2-aminophenylsulfanyl)-1,1,1,3,4,4,4-heptafluorobutane-2,2-diol. In the reaction of the same compounds in dioxane, 2,3-bis(trifluoromethyl)-3,4-dihydro-2H-1,4-benzothiazin-2-ol was formed as a result of primary attack by the amino group in 2-aminobenzenethiol on the epoxy ring. The same product was obtained by treatment with 2-aminobenzenethiol of 2,3-bis(trifluoromethyl)-2H-1,4-benzoxazin-2-ol which was synthesized from 2,3-epoxyoctafluorobutane and 2-aminophenol.     

Thermodynamic study of a series lithium β-diketonates

Thermal behaviour of a series of lithium β-diketonates: Li(dpm) (dpm=dipivaloylmethanate (2,2,6,6-tetramethylheptane-3,5- dionate)), Li(pta) (pta=pivaloyltrifluoracetonate (2,2-dimethyl-6,6,6-trifluoro-3,5-hexanedionate)), Li(tfa) (tfa=trifluoracetylacetonate (1,1,1-trifluoro-2,4-pentandionate)), Li(hfa) (hfa=hexafluoracetylacetonate (1,1,1,5,5,5-hexafluoro-2,4-pentandionate)) has been investigated. Gas phase composition of these complexes has been established. Temperature dependences of vapor pressure of lithium compounds were obtained by static and dynamic methods, and thermodynamic parameters were calculated. Dependence of compound volatility on ligand structure is shown. For Li(dpm) detailed investigation has been done by differential scanning calorimetry (DSC).     

Reactions of 2-acyl-1,3-indandiones

2-Pivaloyl-1,3-indandione reacts with thiosemicarbazide in aqueous base, through two successive retro-Claisen reactions, to yield 1-hydroxy-4-methylphthalazine. The mechanism of this reaction is described. Under similar conditions, 2-benzoyl and 2-acetyl-1,3-indandione, did not undergo the same reaction, a steric factor is considered.     

Reactions of 2-diaminomethylidenecyclohexane-1,3-diones with diethyl malonate

The debenzoylation of 2-[(amino)(benzoylamino)methylidene]cyclohexane-1,3-diones (addition products of cyclohexane-1,3-diones with benzoylcyanamide) affords the corresponding 2-diaminomethylidenecyclohexane-1,3-diones. The latter act as N,N-dinucleophiles in reactions with diethyl malonate in the presence of MeONa to form 6-hydroxy-2-(2,6-dioxocyclohexylidene)-1,2-dihydropyrimidin-4(3H)-ones. This reaction performed at 200 °C in the absence of bases results in the subsequent self-condensation of the dihydropyrimidinones to give 4,5′-bipyrimidine derivatives.     

Reactions of 2-Arylhydrazono-1,3-dicarbonyl Compounds with Ethylenediamine

2-Arylhydrazono-1,3-diketones react with ethylenediamine to give, depending on the substituents, dihydro-1,4-diazepine derivative or N,N'-ethylenebis(1,3-aminovinyl ketones). Treatment of the latter with nickel(II) or copper(II) acetate results in formation of the corresponding metal chelates. Nickel complexes of N,N'-ethylenebis(1,3-aminovinyl ketones) can also be synthesized from 2-arylhydrazono-1,3-diketones and ethylenediamine on a metal template. Reactions of 2-arylhydrazono-3-oxo esters with ethylenediamine yield N,N'-ethylenebis(3-alkyl-2-arylhydrazono-3-oxopropionamides). Ethyl 2-arylhydrazonoacetoacetate reacts with ethylenediamine under mild conditions, affording ethyl 2-p-tolylazo-3-[2-(2-p-tolylhydrazono-1,3-dioxobutylamino)ethylamino]-2-butenoate.     

Perfluoro alkyl 1,3-diketonates of cyclic and acyclic secondary amines

Cyclic and acyclic secondary amines were quaternized with perfluoroalkyl 1,3-diketones to form secondary ammonium perfluoroalkyl 1,3-diketonates in good yields. Saturated cyclic secondary amines, including morpholine, N-acetylmorpholine, 3-methyl-N-acetylpiperidine, 2,2,6,6-tetramethyl-4-aminopiperidine, 4,4-dimethylimidazoline, 1,3-bispiperidine propane, and acyclic secondary amines, di(n-propyl) amine, di(isopropyl) amine, di(n-butyl) amine, and di(isobutyl) amine were reacted with various fluorine-containing 1,3-diketones (1-5) to yield the corresponding 1,3-diketonates (6-29). The compounds were characterized by ¹H, ¹⁹F, and ¹³C NMR, electrospray MS, and elemental analyses. Melting points and T_g values were obtained by DSC. Thermal decomposition data (5% weight loss temperature) were recorded by TGA. X-ray single-crystal structures show that 9 and 26 crystallize in monoclinic space group P2(1)/c.     

Reactions of 2-acyl-1,3-indandiones with monosubstituted hydrazines and hydrazides

Methyl- and phenylhydrazines react with 2-(diphenylacetyl)-1,3-indandione ( 1 ) to yield respectively the 1-(methylhydrazone) and the 1-(phenylhydrazone) of 2-(diphenylacetyl)-1,3-indandione ( 2a and 2b ). In comparison, acetic and benzoic acid hydrazides react with 1 to give respectively the α-(acetylhydrazone) and the α-(benzoylhydrazone) of 2-(diphenylacetyl)-1,3-indandione ( 3a and 3b ). Cyclization of 2a and 2b gives 2,3-disubstituted indeno[1,2-c]pyrazol-4(2H)-ones ( 7a and 7b ). Cyclization of 3a and 3b , followed by methylation, gives 1-methyl- and 2-methyl-3-(diphenylmethyl)indeno[1,2-c]pyrazol-4(1 and 2H)-ones ( 9a and 9b ). 2-Isovaleryl-1,3-indandione reacts with phenylhydrazine to give directly 3-isobutyl-1-phenylindeno[1,2-c]-pyrazol-4(1H)-one ( 10 ).     

Condensation of fluoroalkyl-containing 1,2,3-trione 2-arylhydrazones with methylamine

Fluoroalkyl-containing 1,2,3-trione 2-arylhydrazones react with methylamine in different ways, depending on the substrate structure. Arylhydrazones having a short fluoroalkyl substituent (R_F = CF₃, HCF₂CF₂) react at the carbonyl group adjacent to the nonfluorinated substituent to give 3-alkyl(aryl)-2-aryldiazenyl-3-methylamino-1-polyfluoroalkylprop-2-en-1-ones. Arylhydrazones with a long-chain fluoroalkyl group (R_F = C₃F₇ and longer) and a bulky nonfluorinated group take up methylamine molecule at the carbonyl group linked to the fluorinated substituent, and the subsequent haloform reaction yields N-methyl-2-arylhydrazono-3-oxobutanamides. Both types of products are formed in reactions of methylamine with 1,2,3-triketone 2-arylhydrazones having a long fluoroalkyl group and methyl group at the other carbonyl group. Template condensation of fluoroalkyl-containing 1,2,3-trione 2-arylhydrazones with methylamine over Ni(II) template gives bis[3-alkyl(aryl)-1-polyfluoroalkyl-3-methylamino-2-aryldiazenylprop-2-en-1-onato-N,N′]-nickel(II), regardless of the size of the fluoroalkyl substituent. The same complexes and their copper analogs can be obtained by treatment of 3-alkyl(aryl)-2-aryldiazenyl-3-methylamino-1-polyfluoroalkylprop-2-en-1-ones with the corresponding metal salts.