- PARTIALLY FLUORINATED HETEROCYCLIC COMPOUNDS PART 28. THE HYDROLYSIS OF 1,3,4,5,6,7,8-HEPTAFLUORO-2-NAPHTHYLIDENERHODANINE TO FORM RING-FUSED THIOPHENES. A SIGNIFICANT PROPORTION OF A LINEAR NAPHTHOTHIOPHENE DERIVATIVE ACCOMPANYING AN ANGULAR NAPHTHOTHIOPHENE DERIVATIVE
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1,3,4,5,6,7,8-Heptafluoronaphthalene-2-carbaldehyde (7), prepared via a Grignard reaction from 2-bromo-1,3,4,5,6,7,8-heptafluoronaphthalene (9) with N-methylformanilide, reacted with rhodanine to give 1,3,4,5,6,7,8-heptafluoro-2-naphthylidenerhodanine (5).Hydrolysis of (5) with base gave a mixture of 4,5,6,7,8,9-hexafluoronaphthopthiophene-2-carboxylic acid (11) and 4,5,6,7,8,9-hexafluoronaphthothiophene-2-carboxylic acid (12) resulting from the intermediate thiolate (6) displacing fluorine at sites 3 and 1 in the naphthalene ring in the ratio 22:78 respectively, which represents a significantly high portion of the linearly cyclised product accompanying the angularly cyclised product.Decarboxylation of the mixture of (11) and (12) gave 4,5,6,7,8,9-hexafluoronaphthothiophene (13) and 4,5,6,7,8,9-hexafluoronaphthothiophene (14) respectively, while treatment of the mixture (11) and (12) with diazomethane gave an inseparable mixture of the methyl 2-carboxylates (15) and (16) respectively.
- Brooke, Gerald M.,Meara, Jeremy M.
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- One-pot route to X-perfluoroarenes (X = Br, I) based on FeIII-assisted C-F functionalization and utilization of these arenes as building blocks for crystal engineering involving halogen bonding
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Perfluorinated arenes (benzeneF derivatives, diphenylF, naphthaleneF) were converted into X-perfluoroarenes (X = Br, I) via the developed one-pot protocol based on [Fe(acetylacetonate)3]-assisted C-F functionalization. The syntheses proceed under mild conditions and employ readily available perfluorinated arenes, which are treated with EtMgBr followed by addition of X2/[Fe(acetylacetonate)3] (0.8 mol %); yields range from good to moderate. The σ-hole donor properties of the obtained mono- and di-X-perfluoroarenes and the significance of these species for halogen-bonding-based crystal engineering was illustrated in a series of postsynthetic experiments, all supported by density functional theory (DFT) energy calculations, molecular electrostatic potential (MEP) surface analysis, and the quantum theory of atoms in molecules (QTAIM). These include (i) a solid-state X-ray diffraction study of X-perfluoroarene self-association (dimerization) via iodine σ-hole - electron belt interactions (three X-ray structures) and (ii) verification of X-perfluoroarene σ-hole donor abilities by their interactions with iodides acting as external σ-hole acceptors (five X-ray structures); a Hirshfeld surface analysis was performed for all eight structures.
- Baykov, Sergey V.,Eliseeva, Anastasiya A.,Frontera, Antonio,Galmés, Bartomeu,Kukushkin, Vadim Yu.,Rozhkov, Anton V.
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p. 5908 - 5921
(2020/10/13)
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- Synthesis method of 2-bromoheptafluoronaphthalene compound
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The invention relates to a synthesis method of 2-bromoheptafluoronaphthalene compound. The synthesis method includes the steps of: 1) a fluorination reaction; 2) a hydrazine substitution reaction; and3) a bromination reaction. With octachloronaphthalene as a raw material, the 2-bromoheptafluoronaphthalene is prepared through reactions of fluorination, hydrazine substitution and bromination. The method is low in cost, has simple reaction steps and low toxicity, is convenient to carry out and high in yield, and is suitable for industrial production.
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Paragraph 0014
(2018/06/26)
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- PROCESSES FOR THE PREPARATION OF TETRAKIS (FARYL) BORATE SALTS
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A process for the preparation of organic cation tetrakis(Faryl) borate salts. The process includes preparation of intermediate, mono-hydrazine substituted (Faryl) compound, from (Faryl) compound using hydrazine at temperat
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Page/Page column 3; 14
(2008/06/13)
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- Polycyclic Fluoro-aromatic Compounds. Part 10. Nucleophilic Replacement of Fluorine in Heptafluoro-2-naphthyl-lithium
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Heptafluoro-2-naphthyl-lithium prepered from 2H-heptafluoronaphthalene, reacts with an excess of butyl-lithium to give a 4 : 1 mixture of 6-butyl- and 7-butyl-hexafluoro-2-naphthyl-lithium.Carbonation, bromination, and hydrolysis of all the lithio-compounds gave the expected products.
- Burdon, James,Gill, Harpal S.,Parsons, Ian W.
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p. 2494 - 2496
(2007/10/02)
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- ACTION OF ELECTROPHILIC AGENTS ON POLYFLUORINATED AROMATIC COMPOUNDS. XV. ORIENTATION DURING THE ACTION OF NITRATING AGENTS ON CHLORO- AND BROMOHEPTAFLUORONAPHTHALENES
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1-X-Heptafluoronaphthalenes (X=Cl, Br) react with concentrated nitric acid, with a solution of nitric acid in hydrogen fluoride, and (for X=Cl) with nitronium fluoroborate in a sulfolane medium by a mechanism of the addition type.Derivatives of 1,4-dihydronaphthalene corresponding to the addition of NO2+ at positions 5 and 8 of the initial naphthalenes are formed in ratios of ca. 1:1.5 for X=Cl and ca. 1:2 for X=Br. 2-X-Heptafluoronaphthalenes (X=Cl, Br) react with a solution of nitric acid in hydrogen fluoride to form mixtures of polyfluorinated 1-nitro-1,4-dihydronaphthalenes, among which the isomers corresponding to addition of the nitronium cation at the C4 atom of the initial naphthalene predominate.The ratios of the isomeric products formed in these reactions are compared with the equilibrium ratios of the isomeric polyfluorinated chloro- and bromo-1,1-difluoronaphthalenonium ions, which are the analogs of the hypotetical intermediate compounds (? complexes) in the reactions of polyfluorinated naphthalenes with nitrating agents.
- Osina, O. I.,Chuikova, T. V.,Shteingarts, V. D.
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p. 706 - 716
(2007/10/02)
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