Synthesis of <Emphasis Type="Italic">N</Emphasis>-and <Emphasis Type="Italic">C</Emphasis>-trimethylsilyl-substituded anililes

N-Metallation of bromoanilines with ethylmagnesium bromide followed by a reaction with trimethylchlorosilane provided N-mono and N-bis(trimethylsilyl)bromoanilines depending on the structure of substrate. The metallation of bissilylated bromoanilines with butyllithium permitted the introduction of a trimethylsilyl substituent in the aromatic ring. Previously unknown 2-bromo-N,N-bis(trimethylsilyl)aniline, 2,6-dibromo-N-trimethylsilylaniline, 2,6-dibromo-N,N-bis(trimethylsilyl)aniline, 2-bromo-6-trimethylsilylaniline, 2-bromo-6-trimethylsilyl-N,N-bis(trimethylsilyl)aniline, 2-bromo-6-trimethylsilyl-N-trimethylsilylaniline, 2,4,6-tribromo-N-trimethylsilylaniline, and 2,4,6-tribromo-N,N-bis(trimethylsilyl)aniline were prepared. The structures of the compounds obtained were established by the chromato-mass spectrometry and ¹H, ¹³C, and ²⁹Si NMR spectroscopy.     

Reaction of sodium bis(trimethylsilyl)amide with 2-bromopyridine

A reaction of sodium bis(trimethylsilyl)amide with 2-bromopyridine leads to N,N-bis(trimethylsilyl)- and N,3-bis(trimethylsilyl)-2-pyridinamine.     

Synthesis of <Emphasis Type="Italic">N</Emphasis>-nitro-<Emphasis Type="Italic">N</Emphasis>′-(trimethylsilyl)carbodiimide

Nitration of N,N′-bis(trimethylsilyl)carbodiimide with N₂O₅ or (NO₂)₂SiF₆ afforded N-nitro-N´-(trimethylsilyl)carbodiimide, the first representative of N-nitro carbodiimides. Its further nitration led to the release of CO₂, which is presumably formed in the course of N,N´-dinitrocarbodiimide decomposition. The reactions of N-nitro-N´-(trimethylsilyl)carbodiimide with nucleophiles take place both at the tri methylsilyl group (for example, with NH₃) to give nitrocyanamide salts and at the carbodiimide C atom (for example, with Et₂NH) to give the corresponding nitroguan idines.     

Cycloaminomethylation of dihydric phenols catalyzed by <Emphasis Type="Italic">d</Emphasis>- and <Emphasis Type="Italic">f</Emphasis>-metal compounds

An efficient method has been developed for the synthesis of 7,16,25-triaryl-7,8,16,17,25,26-hexahydro-6H,15H,24H-tribenzo[f,m,t][1,5,8,12,15,19,3,10,17]hexaoxatriazacyclohenicosines, 3,8-diaryl-2,3,4,7,8,9-hexahydrobenzo[1,2-e:4,3-e′]bis[1,3]oxazines, 3,9-bis(chlorophenyl)-3,4,9,10-tetrahydro-2H,8H-benzo[1,2-e:3,4-e′]bis[1,3]oxazines, and 2,9-bis(chlorophenyl)-1,2,3,8,9,10-hexahydrobenzo[1,2-e:6,5-e′]bis-[1,3]oxazines via cycloaminomethylation of pyrocatechol, resorcinol, and hydroquinone with N,N-bis(methoxymethyl) anilines in the presence of samarium catalysts.     

Phosphorylation of Pyrimidinophane in the Reversed Micellar Solutions of Cationic and Nonionogenic Surfactants

Reactions of a macrocycle containing three pyrimidine fragments and N,N′-bis(2-methylthio-6-methylpyrimidin-4-yl)-hexamethylenediamine with p-nitrophenyl bis(chloromethyl)phosphinate in the micellar solutions of cetyltrimethylammonium bromide, polyethyleneglycol-600 laurate and their mixture in chloroform was investigated spectrophotometrically. Catalytic activity of micelles depends on their structure, concentration of surfactants, molar fraction of the latter in solution, and structure of the nucleophilic reagent.     

Synthesis and bromination/dehydrobromination of <Emphasis Type="Italic">N,N</Emphasis>-diallyltrifluoromethanesulfonamide

The reaction of triflluoromethanesulfonamide with allyl bromide in dimethyl sulfoxide gave N,N-diallyltrifluoromethanesulfonamide which was subjected to bromination with 1 and 2 equiv of bromine. The product of bromine addition to both allyl groups, CF₃SO₂N(CH₂CHBrCH₂Br)₂, was found to exist as a mixture of two diastereoisomers at a ratio of 9: 11. Its dehydrobromination by the action of sodium methoxide was chemoselective with successive elimination of one, two, and three hydrogen bromide molecules to afford N-(2-bromoprop-2-en-1-yl)-N-(2,3-dibromopropyl)trifluoromethanesulfonamide, N,N-bis(2-bromoprop-2-en-1-yl)trifluoromethanesulfonamide, and N-(2-bromoprop-2-en-1-yl)-N-(propadienyl)trifluoromethanesulfonamide, respectively.     

Migration of trimethylsilyl group in the reaction of sodium bis(trimethylsilyl)amide with bromobenzene

The reaction of sodium bis(trimethylsilyl)amide with bromobenzene gave a mixture of N,N-bis-(trimethylsilyl)aniline and N,2-bis(trimethylsilyl)aniline, the latter being a rearrangement product formed via 1,3-migration of trimethylsilyl group from the nitrogen atom to the ortho-carbon atom in the benzene ring.     

Reactions of <Emphasis Type="Italic">N</Emphasis>-(Polychloroethylidene)arene-and - trifluoromethanesulfonamides with indoles

N-(Polychloroethylidene)arene-and -trifluoromethanesulfonamides reacted with indole and N-substituted indoles to give the corresponding N-[2,2-dichloro(or 2,2,2-trichloro)-1-(1H-indol-3-yl)ethyl]-substituted sulfonamides. Unlike N-(2,2,2-trichloroethylidene)trifluoromethanesulfonamide, less electrophilic N-(poly-chloroethylidene)arenesulfonamides failed to react with 1-(4-nitrophenyl)-1H-indole. Previously unknown N,N’-bis(2,2-dichloroethylidene)biphenyl-4,4’-disulfonamide reacted with 1-benzyl-1H-indole at both azomethine fragments. Likewise, reactions of 1,6-bis(1H-indol-1-yl)hexane and 1,4-bis(1H-indol-1-ylmethyl)-benzene with N-sulfonyl trichloroacetaldehyde imines involved both indole rings in the former.     

Synthesis of new alkoxysilyl-substituted carboranes

New 1,7-bis(trialkoxysilylpropyl)-m-carboranedicarboxamides were synthesized by the reaction of 3-aminopropyltrialkoxysilanes with either m-carboranedicarboxylic acid chloride in the presence of Et₃N or m-carboranedicarboxylic acid in the presence of N,N´-carbonyl-diimidazole. The synthesized compounds are colorless liquids soluble in benzene, toluene, tetrahydrofuran, diethyl ether, and chloroform and insoluble in water. Structures of the synthesized compounds were established by IR and NMR spectroscopy and confirmed by elemental analysis. The synthesized compounds are interesting starting materials for produc-tion of heat-resistant silicon carborane polymers and metal-carborane-silicon polymers.     

Novel route of the reaction of trifluoromethyl-containing N-methyl(4-ethoxyphenyl)imidazolidin-2-ones with urea

The reactions of perfluorobiacetyl with N-(4-ethoxyphenyl)- and N-methylurea afforded cis- and trans-isomers of 1-methyl-4,5-dihydroxy-4,5-bis(trifluoromethyl)imidazolidin-2-one and 1-(4-ethoxyphenyl)-4,5-dihydroxy-4,5-bis(trifluoromethyl)imidazolidin-2-one in a yield of ～60—75%. N-Alkyl(aryl)bis(trifluoromethyl)imidazooxazoles were obtained as unexpected products in the reaction of 1-alkyl(aryl)-4,5-dihydroxy-4,5-bis(trifluoromethyl)imidazolidin-2-ones with urea in dimethylacetamide. The reaction is accompanied by the rearrangement of imidazolidin-2-ones to N-alkyl(aryl)-5,5-bis(trifluoromethyl)hydantoins with CF₃ group migration from position 5 to position 4 of the starting heterocycle. A similar rearrangement is observed on boiling of the studied imidazolidin-2-ones in dimethylacetamide. The molecular structures of 3-(4-ethoxyphenyl)-5,5-bis(trifluoromethyl)imidazolidine-2,4-dione and 6-(4-ethoxyphenyl)-3a,6a-bis(trifluoromethyl)tetrahydroimidazo[4,5-d]oxazole-2,5-dione were studied by X-ray diffraction analysis.     

Aminomethylation of Thiourea with Formaldehyde and Cyclic Amines

Three-component condensation of thiourea with equimolar amounts of formaldehyde and morpholine afforded N-(morpholin-4-ylmethyl) derivative, whereas analogous reaction with 2 equiv of formaldehyde and amine gave symmetrical N,N′-bis(morpholin-4-ylmethyl)thiourea. In the condensation of thiourea with piperidine and formaldehyde, only symmetrical N,N′-bis(piperidin-1-ylmethyl)thiourea was isolated, regardless of the reactant ratio.     

Cascade Transformations of Trifluoromethanesulfonamide in Reaction with Formaldehyde

Trifluoromethanesulfonamide reacts with paraformaldehyde in acid medium to give both open-chain and cyclic condensation products: bis(trifluoromethylsulfonylamino)methane, N, N-bis(trifluoromethylsulfonylaminomethyl)trifluoromethanesulfonamide, 5-(trifluoromethylsulfonyl)dihydro-1,3,5-dioxazine, 3,5-bis(trifluoromethylsulfonyl)tetrahydro-1,3,5-oxadiazine, 1,3,5-tris(trifluoromethylsulfonyl)hexahydro-1,3,5-triazine, 5,7-bis(trifluoromethylsulfonyl)-1,3,5,7-dioxadiazocane, and 5,7,9-tris(trifluoromethylsulfonyl)-1,3,5,7,9-dioxatriazecane. Amidoalkylation of acetonitrile in the system trifluoromethanesulfonamide-paraformaldehyde-phosphoric acid leads to formation of N-(trifluoromethylsulfonylaminomethyl)acetamide.     

Rare-earth metal dichloride and bis(alkyl) complexes containing amidinate-amidopyridinate ligands: synthesis,structure, and reactivity

A reaction of anhydrous yttrium chloride with an equimolar amount of lithium amidinateamidopyridinate obtained in situ by metallation of N,N’-bis(2,6-dimethylphenyl)-N-{6-[(2,6-dimethylphenyl)amino]pyridin-2-yl}acetimidamide ((2,6-Me₂C₆H₃)NH(2,6-C₆H₃N)N(2,6-Me₂C₆H₃)C(Me)=N(2,6-Me₂C₆H₃), L¹H) (1) with n-butyllithium in THF at–70 °C was used to synthesize the yttrium dichloride complex (L¹)YCl₂(THF)₂ (2). The lutetium bis(alkyl) complex, namely, N’-(2,6-diisopropylphenyl)-N-(2,6-dimethylphenyl-N-{6-[(2,6-dimethylphenyl)amido]pyridin-2-yl}acetimidoamidinatebis(trimethylsilylmethyl)lutetium (4), was obtained by the reaction of N’-(2,6-diisopropylphenyl)-N-(2,6-dimethylphenyl)-N-(6-((2,6dimethylphenyl)amino)pyridin-2-yl)acetimidamide ((2,6-Me₂C₆H₃)NH(2,6-C₆H₃N)N-(2,6-Me₂C₆H₃)C(Me)=N(2,6-Pr ₂ ⁱ C₆H₃), L²H (3)) with an equimolar amount of Lu(CH₂SiMe₃)₃(THF)₂. Complex 4 was found to be very stable and did not show indications of C—H-activation and other kinds of disintegration in benzene or toluene solution even upon prolonged heating at 60 °C. The reaction of complex 4 with an equimolar amount of 2,6-diisopropylaniline in toluene solution at room temperature led to the formation of the lutetium alkyl-anilide complex (L²)Lu(CH₂SiMe₃)(NH-2,6-Pr ₂ ⁱ C₆H₃) (5). A three-component system 4—AlBu ₃ ⁱ —[X][B(C₆F₅)₄] ([X] = [Ph₃C], [PhNHMe₂], the molar ratio of 1: 10: 1) was found to catalyze polymerization of isoprene.     

Reductive acylamination of pyridine <Emphasis Type="Italic">N</Emphasis>-oxide with ethylenediamine and phenylenediamines

Reactions of pyridine N-oxide with ethylenediamine and o- and p-phenylenediamines in the presence of p-toluenesulfonyl chloride in alkaline medium lead to the formation of the corresponding N,N′-bis-(p-tolylsulfonyl)-N,N′-bis(pyridin-2-yl)diamines as a result of reductive acylamination.     

Synthesis of new heterocycles by oxidation of functionalized cyclic derivatives of bis(2-chlorovinyl) sulfide and selenide

Oxidation of 4-substituted 2,6-bis[(E)-chloromethylidene]thiomorpholine with hydrogen peroxide in a mixture of chloroform with acetic acid afforded the corresponding 4-R-2,6-bis[(E)-chloromethylidene]-thiomorpholine 1-oxide. The results of oxidation of bis[(E)-chloromethylidene]-1,4-dichalcogenanes under analogous conditions depended on the chalcogen nature and its position in the ring. The reaction of 2,6-bis[(E)-chloromethylidene]-1,4-dithiane gave 2,6-bis[(E)-chloromethylidene]-1,4-dithiane-1,1,4,4-tetraone, whereas 3,5-bis[(E)-chloromethylidene]-1,4-thiaselenane-1,1-dione was unexpectedly obtained from 3,5-bis[(E)-chloromethylidene]-1,4-thiaselenane. 2,6-Bis[(E)-chloromethylidene]-1,4-thiaselenane and 2,6-bis[(E)-chloromethylidene]-1,4-diselenane decomposed under the oxidation conditions.     

2-Nitroguanidine derivatives: XI. Reactions of <Emphasis Type="Italic">N</Emphasis>′-nitrohydrazinecarboximidamide and 2-methylidene-<Emphasis Type="Italic">N</Emphasis>′-nitrohydrazinecarboximidamide with glyoxal

The reaction of glyoxal with N′-nitrohydrazinecarboximidamide (1-amino-2-nitroguanidine) in the presence of sodium hydroxide at a molar ratio of 1 : 1 : 1 gave N′-nitro-2-(2-oxoethylidene)hydrazinecarboximidamide as a mixture of syn and anti isomers, whereas at a reactant ratio of 1:2:2 N′-nitro-2-[(5-nitroamino-2H-1,2,4-triazol-3-yl)methyl]hydrazinecarboximidamide and 3-nitroamino-4,5-dihydro-1,2,4-triazin-5-ol were formed. N′-Nitro-2-(2-oxoethylidene)hydrazinecarboximidamide reacted with N′-nitrohydrazinecarboximidamide in boiling ethanol to give N′-nitro-2-[(5-nitroamino-2H-1,2,4-triazol-3-yl)methyl]hydrazinecarboximidamide, while in glacial acetic acid 2,2′-(ethane-1,2-diylidene)bis(N′-nitrohydrazinecarboximidamide) was obtained. The latter was also formed in the reaction of glyoxal with N′-nitrohydrazinecarboximidamide in acetic acid at room temperature. The reaction of 2-methylidene-N′-nitrohydrazinecarboximidamide with glyoxal led to the formation of 3-nitroimino-2,3,4-5-tetrahydro-1,2,4-triazine-5-carbaldehyde or 1-(methylideneamino)-2-(nitroimino)imidazolidine-4,5-diol, depending on the conditions.     

Cyclization of trifluoro-<Emphasis Type="Italic">N</Emphasis>-(prop-2-yn-1-yl)methanesulfonamides to <Emphasis Type="Italic">N</Emphasis>-(hydroxymethyl)-1,2,3-triazoles

Three-component heterocyclizations of trifluoro-N-(prop-2-yn-1-yl)methanesulfonamide, trifluoro-N-pheny-N-(prop-2-yn-1-yl)methanesulfonamide, and trifluoro-N,N-di(prop-2-yn-1-yl)methanesulfonamide with formaldehyde and sodium azide afforded N-{[2-(hydroxymethyl)-2H-1,2,3-triazol-4-yl]methyl}-, N-{[2-(hydroxymethyl)-2H-1,2,3-triazol-4-yl]methyl}-N-phenyl-, and N,N-bis{[2-(hydroxymethyl)-2H-1,2,3-triazol-4-yl]methyl}trifluoromethanesulfonamides as the major products together with minor 1-(hydroxymethyl)-1H-1,2,3-triazole isomers.     

Synthesis and conformational analysis of 6-[N,N-bis(dihydroxyphosphorylmethyl)amino]methyl-2-hydroxy-2-oxido-1,4,2-oxazaphosphorinane-4-methylphosphonic acid by NMR spectroscopy

The Kabachnik—Fields methylphosphorylation of 1,3-diaminopropan-2-ol affords a mixture of 1,3-diamino-2-hydroxypropane-N,N,N′,N′-tetrakismethylphosphonic acid and its intramolecular cyclic ester. Subsequent heating of this mixture led to the thermal dehydration of the acid with the 1,4,2-oxazaphosphorinane ring closure and the formation of 6-[N,N-bis(dihydroxyphosphorylmethyl)amino]methyl-2-hydroxy-2-oxido-1,4,2-oxazaphosphorinane4-methylphosphonic acid. A predominant chair conformation of the formed six-membered heterocycle was inferred from the data of 2D homonuclear (¹H, ¹H; J-resolved) and heteronuclear (¹H, ¹³C; HSQC, HMBC) NMR correlation spectra.     

Synthesis of cyclic sulfonamides by reaction of <Emphasis Type="Italic">N</Emphasis>-sulfinyl-3-(trifluoromethyl)aniline with norbornenes

N-Sulfinyl-3-(trifluoromethyl)aniline reacted with bicyclo[2.2.1]hept-2-ene and bicyclo[2.2.1]-hepta-2,5-diene to give the corresponding Diels?Alder adducts which were oxidized to 8-trifluoromethyl-2,3,4,4a,6,10b-hexahydro-5λ⁶-1,4-methanodibenzo[c,e][1,2]thiazine-5,5(1H)-diones. The cycloaddition occurred predominantly with participation of the S=N–C¹=C⁶ fragment of N-sulfinyl-3-(trifluoromethyl)aniline and exclusively at the endo side of bicyclo[2.2.1]heptenes.     

Study of Fluorescence Quenching on Novel Coumarin Derivatives by Aniline in Different Solvents

The steady-state fluorescence quenching of novel coumarin derivatives; 4-(2, 6-dibromo-4-methyl-phenoxymethyl)-benzo[h]chromen-2-one [DMB] and 6-methoxy-4-p-tolyoxymethyl-chromen-2-one [TMC] has been studied in toluene, benzene, dioxane, acetonitrile and tetrahydrofuran [THF] using aniline as a quencher at room temperature with a view to understanding the role of diffusion in the quenching mechanism. The probability of quenching per encounter (p) is calculated in all the solvents. Further, an activation energy for quenching (E _a) was estimated using the values of p and the literature values of activation energy for diffusion (E _d). The magnitudes of these parameters indicate that the fluorescence quenching of these molecules by aniline is not solely due to the material diffusion but there is also a contribution of an activation energy.