58733-41-8Relevant academic research and scientific papers
Mechanistic study on iodine-catalyzed aromatic bromination of aryl ethers by N-Bromosuccinimide
Pramanick, Pranab Kumar,Hou, Zhen-Lin,Yao, Bo
, p. 7105 - 7114 (2017/11/27)
Although iodine-catalyzed reaction has rapid advances in recent years, examples on iodine-catalyzed bromination are rare and the mechanism of these reactions remains unclear. Herein, we reported an I2-catalyzed aromatic bromination of aryl ethers by NBS and presented the details of the mechanistic study including kinetic study and the study of kinetic isotope effects. The study revealed that the reaction was actually catalyzed by IBr formed in the induction period, and the rate-determining step was the HBr-elimination of the Wheland intermediate assisted by IBr.
Impact of electronic modification of the chelating benzylidene ligand in cis-dichloro-configured second-generation olefin metathesis catalysts on their activity
Pump, Eva,Poater, Albert,Zirngast, Michaela,Torvisco, Ana,Fischer, Roland,Cavallo, Luigi,Slugovc, Christian
supporting information, p. 2806 - 2813 (2014/06/24)
A series of electronically modified second-generation cis-dichloro ruthenium ester chelating benzylidene complexes was prepared, characterized, and benchmarked in a typical ring-opening metathesis polymerization (ROMP) experiment. The electronic tuning of the parent chelating benzylidene ligand (2-ethyl ester benzylidene) was achieved by substitution at the 4- and 5-positions with electron-withdrawing nitro or electron-donating methoxy groups. The effect of the electronic tuning on the cis-trans isomerization process was studied experimentally and theoretically. Density functional theory calculations clearly revealed the influence of electronic modification on the relative stability between the cis and trans isomers, which is decisive for the activity of the studied compounds as initiators in ROMP.
AROMATIC RING COMPOUND
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Paragraph 0450; 0451, (2015/01/18)
Provided is an aromatic ring compound having a GPR40 agonist activity. A compound represented by the formula (I): wherein each symbol is as described in the DESCRIPTION, or a salt thereof has a GPR40 agonist activity, and is useful as an agent for the prophylaxis or treatment of diabetes and the like.
Regio- and chemoselective C-H chlorination/bromination of electron-deficient arenes by weak coordination and study of relative directing-group abilities
Sun, Xiuyun,Shan, Gang,Sun, Yonghui,Rao, Yu
supporting information, p. 4440 - 4444 (2013/05/22)
It's all relative: A practical and efficient PdII-catalyzed regio- and chemoselective chlorination/bromination has been developed for the facile synthesis of a broad range of aromatic chlorides. The reaction demonstrates excellent reactivity, good functional-group tolerance, and high yields. A preliminary study was conducted to evaluate relative directing-group abilities of various functionalities. Copyright
Synthesis of macrolide-saccharide hybrids by ring-closing metathesis of precursors derived from glycitols and benzoic acids
Matos, Marie-Christine,Murphy, Paul V.
, p. 1803 - 1806 (2007/10/03)
The benzomacrolactone structural motif is a privileged or evolutionarily selected scaffold that codes properties required for binding to proteins and novel analogues thereof may provide a source of new bioactive compounds. Saccharides are also privileged structures, with (amino)sugars, imino-sugars, and sugar amino acids being applied as scaffolds for the development of nonpeptidal peptidomimetics. The syntheses of novel polyhydroxylated oxamacrolides, structural analogues of natural polyketide derived macrolides, are described herein, providing a basis for their development as scaffolds. The syntheses were carried out from benzoic acids and appropriately protected D-mannitol or D-sorbitol (D-glucitol). Ring-closing metathesis was applied in the macrocyclization step with high E-alkene selectivities being observed. X-ray crystal structures, for two polyhydroxylated derivatives, show that the macrocyclic rings display similar conformations. In addition, intermolecular hydrogen-bonding networks are observed in the lattices.
Process improvements for the preparation of kilo quantities of a series of isoindoline compounds
Watson, Timothy J.,Ayers, Timothy A.,Shah, Nik,Wenstrup, David,Webster, Mark,Freund, David,Horgan, Stephen,Carey, James P.
, p. 521 - 532 (2013/09/05)
A series of isoindoline analogues with either an indazole (HMR 2934, HMR 2651) or benzisoxazole (HMR 2543) appendage were prepared for the proposed treatment of psychiatric disorders such as obsessive compulsive disorder and attention deficit disorder. The isoindoline compounds were prepared by reduction of the corresponding phthalimides with LiAlH4. One compound was not chiral, and the other two required an enantioselective synthesis. The key step for these optically active analogues involved the coupling by an SN2 process of either a piperazynyl intermediate or a piperdinyl intermediate with methyl 3-benzyloxy-2-trifluoromethansulfonatopropionate. The products for these two analogues had >98% ee. Process improvements led to the multi-kilogram syntheses of each of these compounds.
