Reactions involving fluoride ion. Part 21 [1]. Nucleophilic substitution reactions of perfluorocyclobutene oligomers

Reaction of perfluorocyclobutene oligomers, (1) - (4), with some simple nucleophiles gives products arising from S_N2′ displacement [N.B. this term is used here to describe the overall process of addition of a nucleophile to an alkene and elimination of an allylic fluorine and is not meant to imply that the reaction is concerted] or vinylic substitution of fluorine, or a mixture of both processes. The reactivity of the dimers, (1) and (2), is much greater than that of acyclic analogues and this can be attributed to the ring strain present in these compounds.     

Studies in azide chemistry. Part X [1]. Synthesis of perfluoro-2-azido-1-azacyclohexene

Perfluoro-2-azido-1-azacyclohexene can be prepared by treating perfluoro-1-azacyclohexene with an equimolar proportion of sodium azide (in acetonitrile) or azidotrimethylsilane under mild conditions; ¹⁹F n.m.r. analysis reveals that this new imidoyl azide participates in ring ° chain valence tautomerism, the tetrazolo-isomer constituting 19% of the equilibrium mixture at 35 °C.     

Fluorocarbon derivatives of nitrogen. Part VII [1]. Reaction of N-iminopyridinium ylide with perfluoro-1-azacyclohexene,perfluoro-2-azapropene,and perfluoroacetonitrile

The novel ylides (II) and (III) have been obtained $\text{via}$ treatment of perfluoro-1-azacyclohexene and perfluoro-2-azapropene, respectively, with $\text{N}$-iminopyridinium ylide (I) generated $\text{in}$$\text{situ}$ from $\text{N}$-aminopyridinium iodide and anhydrous potassium carbonate in methylene chloride. A mixture of the $\text{s}$-triazolo[1,5-$\text{a}$]pyridine (IV) and a compound thought to be its dihydro-analogue (V) were isolated following attack on perfluoroacetonitrile by the parent ylide (I); the former product was also prepared by heating 1,2-diamino-pyridinium iodide with trifluoroacetic anhydride.     

Heterocyclic polyfluoro-compounds. Part 36 [1]. The reaction of 2,2-bis(trifluoromethyl)-3,4-difluoro-oxetan with aluminium trichloride

2,2-Bis(trifluoromethyl)-3,4-difluoro-oxetan, when treated with aluminium trichloride at 30 to 90 °C, undergoes $\text{cis}$ to $\text{trans}$ isomerisation, non-stereospecific exchange of the 4-fluorine by chlorine, and more slowly of the 3-fluorine, and ring opening to give preferentially the alcohols (CF₃)₂C(OH)CXCHCl (X  F or Cl), together with the aldehydes (CF₃)₂CClCHXCHO and acid chlorides (CF₃)₂CClCHXCClO (X  F or Cl). A large number of unidentified minor products were also obtained from the reactions carried out at the higher temperatures.     

Photochemische Umwandlungen. XXVII [1]. Ein «stabiles» Benzoloxid Vorläufige Mitteilung

By thermal isomerization of the 3-oxa-6.7-diphenyl-tetracyclo [3.2.0.0^{2, 7}. 0^{4, 6}]-heptane-1. 5-dicarbomethoxylate (4) besides the oxanorbornadiene 3 and the hydroxy-fulvene 7, the ‘stable’ benzeneoxide 7-oxa-2.5-diphenyl-bicyclo [4.1.0] hepta-2.4-diene-3.4-dicarbomethoxylate (5) has been isolated. In the temperature range ?50 to 170°C no equilibration with the monocyclic oxepine 6 has been detected.     

Heterocyclic derivatives of purines. 5. Nucleophilic substitution in series of imidazo[1,2-f]purine derivatives

The chlorination of 1,8-dimethyl-7-phenylimidazo[1,2-f]xanthine with an equimolar amount of PCl₅ in POCl₃ leads to 2,4-dichloro-8-methyl-7-phenylimidazo[1,2-f]-purine. The possibility of substitution of the halogen atoms in reactions with nucleophilic reagents to give various 4-amino and 2,4-diamino derivatives was studied.See [1] for Communication 4.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 407–412, March, 1984.     

Fluorinated dioxolanes. 3. Nucleophilic reactions of perfluoro-4-methyl-1,3-dioxolanes

Conclusions Perfluoro-2,4-dimethyl-2-fluorocarbonyl-1,3-dioxolane reacts with sodium carbonate to give perfluoro-2-methylene-2-methyl-1,3-dioxolane. Under the reaction conditions, the latter dimerizes to perfluoro-2-(2,4-dimethyl-1,3-dioxolan-2-ylmethylene)-4-methyl-1,3-dioxolane, and on treatment with CsF is converted into perfluoromethyl-(1,3-dioxolany-2-yl)ketone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 938–942, April, 1989.     

Reactions involving fluoride ion. Part 33 [1]. Perfluoroaza-alkylation of fluorinated heteroaromatics with perfluoro-1-methyl-1,3-diazacyclopent-2-and -3-ene

The nitrogen anion (1), generated by reaction of fluoride ion with (2), can be trapped by fluorinated heteroaromatics. Reaction of (1) with pentafluoropyridine gives a mono-substituted product. Mono- and di-substituted products are obtained with tetrafluoro-pyridazine and -pyrimidine, and fluoride ion catalysed isomerisation is observed. The mechanistic consequences of this are discussed. Reaction of (1) with trifluoro-1,3,5- triazine gives a tri-substituted product.     

Nucleophilic substitution reactions in 4-halonitro-pyrazolecarboxylic acids

The reaction of 4-bromo-1-methyl-3-nitropyrazole-5- and 4-bromo-1-methyl-5-nitro-pyrazole-3-carboxylic acids with arylamines in aqueous solution in the presence of monovalent copper salts leads to the formation of 4-arylamino- and 4-hydroxy substituted nitropyrazolecarboxylic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 328–330, March, 1986.     

Heterocyclic polyfluoro-compounds. Part 38[1]. Photochemical addition of but-2-yne to pentafluoropyridine to give 1:1 and 2:1 adducts

Pentafluoropyridine adds photochemically to but-2-yne to give two 1:1 adducts, 1,2,4,5,6-pentafluoro-7,8-dimethyl- 3-aza- and 1,2,5,6,8-pentafluoro-3,4-dimethyl-7-aza-bicyclo- [4.2.0] octa-2,4,7-triene and a 1:2 adduct, 1,2,5,6,8-pentafluoro- 3,4,9,10-tetramethyl-7-azatricyclo[4.2.2.0^2,5] deca- 3,7,9-triene.     

Nucleophilic substitution in 4-bromo-5-nitrophthalonitrile: XIV. Synthesis and properties of 4,5-bis[4-(1-methyl-1-phenylethyl)phenoxy]phthalonitrile and phthalocyanines therefrom

4,5-Bis[4-(1-methyl-1-phenylethyl)phenoxy]phthalonitrile was prepared by the nucleophilic substitution of the nitro group and bromine in 4-bromo-5-nitrophathalonitrile. The product was used to synthesize the corresponding octasubstituted phthalocyanine, as well as its magnesium, copper, zinc, cobalt, and nickel complexes. The spectral properties of the synthesized phthalocyanines were studied.     

Nucleophilic substitution in 4-bromo-5-nitrophthalodinitrile: VIII. Synthesis of 4-(benzotriazol-1-yl)-5-[4-(1-methyl-1-phenylethyl)phenoxy]phthalodinitrile and phthalocyanines on its basis

Nucleophilic aromatic substitution of the bromine atom in 4-bromo-5-nitrophthalodinitrile by a 2-aminophenylamine residue followed by conversion of the resulting compound to 4-(1-benzothiazol-1-yl)-5-nitrophthalodinitrile and nucleophilic substitution of the nitro group by a 4-(1-methyl-1-phenylethyl)-phenoxy group gave 4-(benzotriazol-1-yl)-5-[4-(1-methyl-1-phenylethyl)phenoxy]phthalodinitrile. The latter product was reacted with certain metal acetates and chlorides to obtain the corresponding metal complexes of octasubstituted phthalocyanines. Spectral properties of the complexes were studied.     

Nucleophilic substitution in 4-bromo-5-nitrophthalodinitrile: X. Synthesis of 4-(1-benzotriazolyl)-5-(1(2)-naphthyloxy)-phthalodinitriles and related phthalocyanines

4-(1-Benzotriazolyl)-5-[1(2)-naphthyloxy]phthalodinitriles were obtained by nucleophilic substitution of bromine and nitro group in 4-bromo-5-nitrophthalodinitrile. These compounds were used for the synthesis of the corresponding octa-substituted phthalocyanines. Spectral data of the compounds obtained were examined.     

Heterocyclic polyfluoro-compounds. Part 34 [1]. Two-way photochemical addition of hexafluoroacetone to 1,2-dichlorofluoroethylene,and the preparation of an oxete

The well-known Paterno-Büchi reaction, which involves oxetan formation by the photochemical addition of a carbonyl compound to a carbon-carbon double bond [2], was extended to the fluorocarbon field by Harris and Coffman [3], who described the photochemical addition of fluoroaldehydes, fluoroketones, and fluoroacyl fluorides to terminal perfluoroolefins and chlorotrifluoroethylene, e.g., Subsequently, Bissel and Fields reported that low yields of oxetans were obtained from acetaldehyde and the olefins, CF₂CF₂, CF₂CFCl, and CF₂CCl₂ [4]. The reaction of hexafluoroacetone with hexafluoropropene involves the triplet state of the ketone [5].     

Polyfluorocycloalkenes. Part XVI [1]. Some addition reactions of 1-trifluoromethylnonafluorocyclohex-1-ene

Reactions with alcohols and base replaced the vinylic fluorine of 1-trifluoromethylnonafluorocyclohex-1-ene(I) by methoxy and ethoxy groups. Fluorination with cobaltic fluoride gave, from the former, a number of saturated polyfluoro-ethers. Oxidation of the alkoxy-cycloalkenes gave hexafluoroglutaric acid. Cycloalkene I gave which ammonia an imino-enamine, which was hydrolysed by dilute acid to a keto-enamine. I was defluorinated by heated iron to octafluorotoluene.     

Fluorocarbon derivatives of nitrogen. Part IV [1]. Perfluoro-1-azacyclohex-1-ylcaesium

Caesium fluoride combined with perfluoro-1-azacyclohexene in acetonitrile to yield perfluoro-1-azacyclohex-1-ylcaesium (1), which was characterised by ¹⁹F n.m.r. spectroscopy and by treatment with iodomethane to give 2,2,3,3,4,4,5,5,6,6-decafluoro-1-methyl-1-azacyclohexane (2). Attempts to derivatize the caesium salt with chlorotrimethylsilane provided fluorotrimethylsilane, perfluoro-[1-(1-azacyclohex-1-en-2-yl)-1-azacyclohexane] (4), and 2-chloro-3,3,4,4,5,5,6,6-octafluoro-1-azacyclohexene (5); information on the course of this reaction was obtained through experiments in which perfluoro-1-azacyclohexene was shown to undergo conversion into its chloro-analogue (5) and its dimer (4) $\text{via}$ treatment with chlorotrimethylsilane and fluoride ion, respectively. Aluminium chloride also converts perfluoro-1-azacyclohexene into its chloro-analogue (5).     

Pyrroloquinolines and pyrroloisoquinolines. 4. Nucleophilic substitution in the pyrroloisoquinoline series

The reactivity of 1H-pyrrolo[2,3-f]isoquinoline with respect to nucleophilic substitution was studied in the case of the Chichibabin reaction and related transformations.See [1] for communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 495–497, April, 1984.