1836-06-2Relevant articles and documents
Synthesis method for aromatic ring bromination of acetophenones derivative
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Paragraph 0067-0070, (2019/06/11)
The invention relates to a synthesis method for aromatic ring bromination of an acetophenones derivative, and belongs to the technical field of organic synthesis. The synthesis method consists of twokinds of synthesis methods: method A, adding the acetophenone derivative into a first oxidizing agent and stirring to form a suspension system, controlling the temperature of the suspension system tobe 10-50 DEG C, adding a first reducing agent or a second reducing agent, stirring and reacting for 2-20 h, and performing aftertreatment after the reaction is completed to obtain the aromatic ring brominated acetophenone derivative; method B, adding the acetophenone derivative into the second reducing agent and stirring to form a suspension system, controlling the temperature of the suspension system to be 10-50 DEG C, then adding a second oxidizing agent or the first oxidizing agent, stirring and reacting for 2-20 h, and performing aftertreatment after the reaction is completed to obtain thearomatic ring brominated acetophenone derivative. According to the synthesis method provided by the invention, an inorganic and non-toxic bromination reagent is used, water is used as a reaction solvent, the prepared product is mutually incompatible with water, so that separation and the aftertreatment are convenient to perform, therefore, the synthesis method of the invention is applicable to large-scale industrial production of intermediate products for aromatic ring bromination of the acetophenones derivative.
Iridium-Catalyzed C(sp3)?H Addition of Methyl Ethers across Intramolecular Carbon–Carbon Double Bonds Giving 2,3-Dihydrobenzofurans
Ohmura, Toshimichi,Kusaka, Satoshi,Torigoe, Takeru,Suginome, Michinori
supporting information, p. 4448 - 4453 (2019/09/16)
Intramolecular addition of an O-methyl C(sp3)?H bond across a carbon-carbon double bond occurs in the iridium-catalyzed reaction of methyl 2-(propen-2-yl)phenyl ethers. The Ir/(S)-DTBM-SEGPHOS catalyst promotes the reaction efficiently in toluene at 110–135 °C to afford 3,3-dimethyl-2,3-dihydrobenzofurans. Enantioselective C(sp3)?H addition is achieved in the reaction of methyl 2-(1-siloxyethenyl)phenyl ethers, affording enantioenriched 3-hydroxy-2,3-dihydrobenzofuran derivatives with up to 96% ee. (Figure presented.).
Dependence of mesomorphism on flexibility of lateral and terminal groups of chalconyl esters
Patel, Priya K.,Shah
, p. 1 - 9 (2016/12/22)
A novel liquid crystalline homologous series of chalconyl vinyl esters with a lateral bromo substituent RO─C6H4─CH═CH─COO─C6H3─(Br)─CO-CH═CH─C6H4─C12H25(n) has been synthesized and studied with a view to understanding and establishing the relation between the molecular structure and liquid crystal (LC) behavior in terms of molecular flexibility of the lateral and terminal groups. The novel homologous series consists of thirteen (C1–C18) homologues, whose enantiotropic nematic and smectic mesomorphism commences from the C4, (C4–C18) and the C5, (C5–C18) homologue, respectively. The rest of the homologues (C1, C2, C3) are nonliquid crystals (NLC). Mesomorphism and transition temperatures were examined using an optical polarising microscope (POM) equipped with a heating stage. Textures of nematic phase are threaded or Schlieren and those of the Smectic-A or Smectic-C are focal conic. Analytical, thermal and spectral data supported molecular structures of the novel homologues. Thermal for smectic and nematic are 87.5°C and 101.1°C, respectively, whose, total mesophase length ranges from 17°C to 30°C at C14 and C7 homologue, respectively. The mesomorphic transition temperature ranges are between 70°C and 113°C.
