53334-33-1Relevant academic research and scientific papers
Mechanistic studies of intramolecular CH insertion reaction of arylnitrenes: Isotope effect, configurational purity and radical clock studies
Murata, Shigeru,Tsubone, Yasuhiro,Kawai, Reina,Eguchi, Daisuke,Tomioka, Hideo
, p. 9 - 20 (2005)
In order to reveal the mechanism of the intramolecular CH insertion of arylnitrenes, three experiments were carried out: measurement of isotope effects, determination of the extent of configurational retention and radical clock studies. Irradiation of the deuterium-substituted azide 4-d in an inert solvent exclusively afforded the indolines 5-h and 5-d, in which the kinetic isotope effect kH/kD on the intramolecular CH insertion of the nitrene was evaluated as 12.6-14.7 at room temperature. A chiral Chromatographic analysis of the indoline 11 obtained from the optically active azide (S)-6 revealed that the enantiomeric purity of the starting azide was almost completely lost during the intramolecular CH insertion of the photolytically generated nitrene (enantiomeric excess 10%). The thermolysis of the azide 7 at 180°C mainly gave a mixture of the cyclopropyl ring-opened products 20-22, together with the intramolecular CH insertion product with an intact cyclopropyl ring 19. On the basis of these observations, we concluded that the intramolecular CH insertion of the nitrene proceeds primarily by the hydrogen abstraction-recombination mechanism. We propose, however, a small contribution of the concerted mechanism to the intramolecular CH insertion, based on the solvent dependence of the isotope effect and the extent of the configurational retention. Copyright
A Synthetic Route to Chiral Benzo-Fused N-Heterocycles via Sequential Intramolecular Hydroamination and Asymmetric Hydrogenation of Anilino-Alkynes
Xu, Cong,Feng, Yu,Li, Faju,Han, Jiahong,He, Yan-Mei,Fan, Qing-Hua
, p. 3979 - 3990 (2019/11/14)
An efficient sequential intramolecular hydroamination/asymmetric hydrogenation reaction under catalysis of a single chiral ruthenium complex or a binary system consisting of achiral gold complex and chiral ruthenium complex has been reported. A diverse range of enantioenriched benzo-fused N-heterocycles, including 1,2,3,4-tetrahydroquinoline, indoline, and 2,3,4,5-tetrahydro-1H-benzo[b]azepine derivatives, were obtained from anilino-alkynes in high yields (up to 98%) with moderate to excellent enantioselectivities (up to 98% ee) under mild conditions. This protocol features good functional group tolerance and high atom economy. Furthermore, this catalytic protocol is applicable to gram-scale synthesis of a naturally occurring alkaloid, (-)-Angustureine.
Structural development of liver X receptor (LXR) antagonists derived from thalidomide-related glucosidase inhibitors
Noguchi-Yachide, Tomomi,Miyachi, Hiroyuki,Aoyama, Hiroshi,Aoyama, Atsushi,Makishima, Makoto,Hashimoto, Yuichi
, p. 1750 - 1754 (2008/09/17)
Following our previous discovery of LXR antagonistic activity of 2′-substituted phenylphthalimides derived from thalidomide-related glucosidase inhibitors, structure-activity studies and further structural development led to 5-chloro-N-2′-n-pentylphenyl-1,3-dithiophthalimide (5CPPSS-50), with IC50 values of about 10 and 13 μM for LXRα and LXR β, respectively.
Para-bromination of ortho-alkyl anilines
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, (2008/06/13)
A process of selectively preparing p-bromo-o-alkylanilines (e.g. 4-bromo-2-methylaniline) by reacting o-alkylanilines (e.g., 2-methylaniline) with unadsorbed bromine in a solvent selected from the group consisting of an inert di- tri- or tetrahaloaliphatic hydrocarbon (e.g., dichloromethane and dibromomethane), an alkyl nitrile (e.g., acetonitrile) and mixtures thereof.
