17628-72-7Relevant academic research and scientific papers
Asymmetric alcoholytic kinetic resolution of styrene oxide catalysed by chiral metal-organic framework crystals
Tanaka, Koichi,Otani, Ken-Ichi
, p. 2389 - 2391 (2010)
The methanolytic kinetic resolution of styrene oxide catalyzed by chiral metal-organic framework crystals afforded both 2-methoxy-2-phenylethanol and unreacted styrene oxide in good enantiomeric excesses.
Stereospecific lewis acid catalyzed methanolysis of styrene oxide
Moberg, Christina,Rakos, Laszlo,Tottie, Louise
, p. 2191 - 2194 (1992)
The methanolysis of (R)-styrene oxide catalyzed by SnCl4 has been found to proceed with complete regioselectivity with nucleophilic attack at the benzylic position, and with inversion of configuration at the benzylic carbon as the predominant stereochemical course, affording (S)-2-methoxy-2-phenylethanol (95% ee) in high yield.
Cellulose sulfate: An efficient heterogeneous catalyst for the ring-opening of epoxides with alcohols and anilines
Chaudhary, Pooja,Deepa,Meena, Dhan Raj,Aalam, Mohd Jubair,Yadav, Geeta Devi,Singh, Surendra
, p. 1834 - 1846 (2021/05/10)
Cellulose sulfate was synthesized by esterification of α-cellulose with concentrated sulfuric acid at ?10°C in ethanol. Cellulose is mainly sulfated on 3-, 6- and 3, 6-positions of the cellulose. It acts as a heterogeneous catalyst for the ring-opening of epoxides with alcohols or anilines and the Friedel-Crafts reaction between N-benzylindole and crotonaldehyde at room temperature. Methanolysis of cyclic epoxides, styrene oxide, terminal aliphatic epoxides, and glycidyl ethers were carried out using the catalyst (0.4–6.8 mg/mmol of epoxide) and afforded the corresponding products in 53–97% isolated yields after 10 min–24 h. Cellulose sulfate was successfully recycled and reused up to 3 catalytic cycles for the ring-opening of styrene oxide with methanol.
Use of trichloroacetonitrile as a hydrogen chloride generator for ring-opening reactions of aziridines
Toda, Yasunori,Matsuda, Riki,Gomyou, Shuto,Suga, Hiroyuki
supporting information, p. 3825 - 3829 (2019/04/17)
Regioselective ring-opening reactions of 2-aryl-N-tosylaziridines are described, in which hydrogen chloride is generated by photodegradation of trichloroacetonitrile. HCl adducts are obtained in high yields in 1,4-dioxane, whereas methanol adducts are pre
Effect of Solvent Polarity on Enantioselectivity in Candida Antarctica Lipase B Catalyzed Kinetic Resolution of Primary and Secondary Alcohols
Kitamoto, Yuichi,Kuruma, Yosuke,Suzuki, Kazumi,Hattori, Tetsutaro
supporting information, p. 521 - 527 (2015/08/11)
The Candida antarctica lipase B (CAL-B) catalyzed kinetic resolution of primary and secondary alcohols via acetylation is dependent on the permittivity (ε) of the reaction solvent. For example, the enantiomeric ratio (E) vs ε plot for the acetylation of 1-(naphth-2-yl)ethanol (1) exhibits a convex shape, taking the maximum E value at a medium ε value (11.2), whereas the same plot for the acetylation of benzyl 3-hydroxybutylate (3) exhibits a concave shape, taking the minimum E value at a similar ε value (11.6). Kinetic studies reveal that the difference in shape of the E vs ε plots originates from the relative reaction rate between the enantiomers with different Michaelis constants (Km). Thus, when the enantiomer with a larger Km value in the middle ε region reacts more slowly than its antipode, the ε dependence of E exhibits a convex shape. On the other hand, when the enantiomer reacts more quickly, it exhibits a concave shape. The E vs ε plot for the acetylation of 2-methoxy-2-phenylethanol (7) exhibits a convex shape with the maximum E value (20) at ε = 14.1. The E value can be further improved to almost reach the efficiency required for industrial applications (E ≈ 30) by the addition of a nitro compound.
Highly efficient and chemoselective zinc-catalyzed hydrosilylation of esters under mild conditions
Kovalenko, Oleksandr O.,Adolfsson, Hans
supporting information, p. 2785 - 2788 (2015/02/05)
A mild and highly efficient catalytic hydrosilylation protocol for room-temperature ester reductions has been developed using diethylzinc as the catalyst. The methodology is operationally simple, displays high functional group tolerance and provides for a facile access to a broad range of different alcohols in excellent yields.
Microstructure analysis of a CO2 copolymer from styrene oxide at the diad level
Wu, Guang-Peng,Zu, Yu-Ping,Xu, Peng-Xiang,Ren, Wei-Min,Lu, Xiao-Bing
, p. 1854 - 1862 (2013/09/02)
A large amount of interesting information on the alternating copolymerization of CO2 with terminal epoxides has already been reported, such as the regiochemistry of epoxide ring-opening and the stereochemistry of the carbonate unit sequence in the polymer chain. Moreover, the microstructures of CO2 copolymers from propylene oxide and cyclohexene oxide have also been well-studied. However, the microstructure of the CO2 copolymer from styrene oxide (SO), an epoxide that contains an electron-withdrawing group, has not yet been investigated. Herein, we focus on the spectroscopic assignment of the CO2 copolymer from styrene oxide at the diad level by using three kinds of model dimer compounds, that is, T-T, H-T, and H-H. By comparing the signals in the carbonyl region, we concluded that the signals at δ=154.3, 153.8, and 153.3 ppm in the 13C NMR spectrum of poly(styrene carbonate) were due to tail-to-tail, head-to-tail, and head-to-head carbonate linkages, respectively. Moreover, various isotactic and syndiotactic model compounds based on T-T, H-T, and H-H (dimers (R,R)-T-T, (S,S)-T-T, and (R,S)-T-T; (R,R)-H-T, (S,S)-H-T, and (R,S)-H-T; (R,R)-H-H, (S,S)-H-H, and (R,S)-H-H) were synthesized for the further spectroscopic assignment of stereospecific poly(styrene carbonate)s. We found that the carbonate carbon signals were sensitive towards the stereocenters on adjacent styrene oxide ring-opening units. These discoveries were found to be well-matched to the microstructures of the stereoregular poly(styrene carbonate)s that were prepared by using a multichiral CoIII-based catalyst system. T-T races: The spectroscopic assignment of regio- and stereoregular poly(styrene carbonate)s at the diad level was performed by 13C NMR studies of three kinds of model compounds, as well as their syndiotactic (R,S) and isotactic (R,R or S,S) dimers. Copyright
Enantioselective ring-opening reaction of epoxides with MeOH catalyzed by homochiral metal-organic framework
Tanaka, Koichi,Otani, Ken-Ichi,Murase, Takanori,Nishihote, Shyota,Urbanczyk-Lipkowska, Zofia
experimental part, p. 709 - 714 (2012/08/08)
Two new copper metal-organic frameworks containing 2,2′-dihydroxy-1, 1′-binaphthalene-5,5′-dicarboxylic acid (5,5′-H 2BDA) and 2,2′-dihydroxy-1,1′-binaphthalene-4,4′- dicarboxylic acid (4,4′-H2BDA) have been prepared. X-ray structure determination of [Cu2(5,5′-BDA)2(H 2O)2]·MeOH·2H2O (MOF-1) and [Cu2(4,4′-BDA)2(H2O)2] ·4H2O (MOF-2) revealed similar 2D sheet structures, containing square-grid coordination networks, but differences in the stacking motif. The desolvated MOF-1 and -2 were used as Lewis acid catalysts in the asymmetric ring-opening reaction of epoxides with MeOH.
The diastereoselective formation of tetraalkoxy[4]resorcinarenes derived from (-)-(2R)-2-methoxy-2-phenylethanol and proof of absolute configurations
Bulman Page, Philip C.,Chan, Yohan,Heaney, Harry,McGrath, Matthew J.,Moreno, Eduardo
experimental part, p. 5347 - 5354 (2011/11/13)
The preparation of optically pure (-)-3-[(2R)-2-methoxy-2-phenylethoxy] phenol from resorcinol monobenzoate and its conversion into diastereoisomeric tetraalkoxyresorcin[4]arenes together with proof of the absolute configurations of the products is reported. The results of the study indicate that diastereoselective ring closure of linear tetrameric intermediates is controlled by the steric demand of the alkyl group in the precursor 3-alkoxyphenol.
A diels-alder approach to (-)-ovalicin
Tiefenbacher, Konrad,Arion, Vladimir B.,Mulzer, Johann
, p. 2690 - 2693 (2008/03/12)
A round at the Oval: The antiangiogenic activity of the natural product ovalicin has sparked significant interest. A highly efficient enantio- and diastereoselective total synthesis of ovalicin proved successful in which the key step involved an endo sele
