6290-24-0Relevant articles and documents
Ligand-free Cu(ii)-catalyzed aerobic etherification of aryl halides with silanes: An experimental and theoretical approach
Ahmed, Muhammad Naeem,Ahmad, Khalil,Yasin, Khawaja Ansar,Farooq, Tayyaba,Khan, Bilal Ahmad,Roy, Soumendra K.
, p. 11316 - 11333 (2019/07/31)
Owing to their wide occurrence in nature and immense applications in various fields, the synthesis of aryl alkyl ethers has remained a focus of interest. In contrast to the conventional/traditional methods of etherification, herein, we have reported a more efficient method, which is better yielding and more general in application. The etherification of aryl halides by alkoxy/phenoxy silanes was catalyzed by copper acetate in the presence of cesium carbonate and oxygen in DMF at 145 °C. All the as-synthesized compounds were characterized via the 1H-NMR and 13C-NMR spectroscopic techniques. Density functional theory calculations using the B3LYP functional were performed to elucidate the reaction mechanism. The C-O coupling reaction between 2-nitroiodobenzene and tetramethoxysilane was used as a model reaction. The activation energy barriers for the generation of catalytic species (31.6 kcal mol-1) and the σ-bond metathesis (16.0 kcal mol-1), oxidative addition/reductive elimination (20.3 kcal mol-1), halogen atom transfer (19.2 kcal mol-1) and single electron transfer (SET) (29.5 kcal mol-1) mechanisms for the C-O coupling reaction were calculated. Calculations for the key reaction steps were repeated with the B3PW91, PBEH1PBE, wB97XD, CAM-B3LYP and mPW1LYP functionals. The formation of catalytic species via a single electron transfer reaction between tetramethoxysilane and copper acetate, formation of methoxy radicals and methoxylation of copper showed an overall energy barrier of 31.6 kcal mol-1, and therefore is the rate determining step.
SKIN WHITENING AGENT CONTAINING NOVEL CYCLIC COMPOUND
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Paragraph 0108; 0109, (2016/08/29)
Provided is a derivative or a polyhydroxy cyclic compound represented by Formula I or a pharmacologically acceptable salt thereof with excellent whitening effects, comprising; wherein {circle around (A)} is derived from an aromatic cyclic compound, B is hydrogen, oxo (═O), amino (—NH2), imino (═NH), or a saturated or unsaturated straight or branched alkyl, alkoxy, monoalkylamino, or dialkylamino group having 1 to 10 carbon atoms, Cn, Cn+1and Cn+2 are three neighboring carbon atoms present in the aromatic cyclic compound, wherein n is a positive integer, R1 is hydrogen, hydroxy, or a saturated or unsaturated straight or branched alkyl or alkoxy group, X and Y are selected from a group consisting of hydrogen, hydroxy, and a saturated or unsaturated straight or branched alkoxy, or acyloxy group, and one of X and Y is hydrogen, R2, R3, R4 and R5 are each independently at least one substituent selected from a group consisting of hydrogen, alkyl, alkoxy, acyloxy, acyloxymethyl, oxo, hydroxy, vinyl, nitrile, carboxaldehyde, carbonitrile and aldehyde.
New cyclic skin whiteninig agent
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Paragraph 0115-0116, (2016/11/21)
In the present invention, provided is a skin whitening agent, which is easily synthesized without side effects for skin and has an outstanding effect of inhibiting pigmentation on skin due to an outstanding effect of inhibiting the creation of melanine where a cyclic derivative compound or pharmaceutically acceptable salt thereof has a chemical structure in formula (I) and is accordingly used to achieve the purpose of the present invention. In the present invention, provided is a cyclic derivative compound or pharmaceutically acceptable salt thereof, which has an effect of whitening skin and a chemical structure in formula (I) where A is derived from an aromatic cyclic compound; B is derived from among hydrogen, O which is oxo, NH_2 which is amino, NH which is imino, C1-C10 of saturated or unsaturated straight or branched chain alkyl group, alkoxy, mono alkyl amino group or dialkyl amino group; and C_n, C_n+1 and C_n+2 are three neighboring carbons in the cyclic compound wherein n is a positive integer.COPYRIGHT KIPO 2015
