5396-65-6Relevant academic research and scientific papers
O-(tert-butyl) Se-phenyl selenocarbonate: A convenient, bench-stable and metal-free precursor of benzeneselenol
Temperini, Andrea,Siciliano, Carlo
, (2020/06/17)
A study by our laboratory shows that air, light and moisture stable O-(tert-butyl) Se-phenyl selenocarbonate could be employed as a safer, practical and efficient alternative to generate “in situ” benzeneselenol or benzeneselenolate anion under different and transition metal-free conditions. This procedure seems to be of general application since the nucleophilic selenium species obtained can be trapped by electrophiles such as alkyl halides, epoxides and electron-deficient alkenes and alkynes under different reaction conditions.
Biphasic Bioelectrocatalytic Synthesis of Chiral β-Hydroxy Nitriles
Dong, Fangyuan,Chen, Hui,Malapit, Christian A.,Prater, Matthew B.,Li, Min,Yuan, Mengwei,Lim, Koun,Minteer, Shelley D.
supporting information, p. 8374 - 8382 (2020/05/22)
Two obstacles limit the application of oxidoreductase-based asymmetric synthesis. One is the consumption of high stoichiometric amounts of reduced cofactor. The other is the low solubility of organic substrates, intermediates, and products in the aqueous phase. In order to address these two obstacles to oxidoreductase-based asymmetric synthesis, a biphasic bioelectrocatalytic system was constructed and applied. In this study, the preparation of chiral β-hydroxy nitriles catalyzed by alcohol dehydrogenase (AdhS) and halohydrin dehalogenase (HHDH) was investigated as a model bioelectrosynthesis, since they are high-value intermediates in statin synthesis. Diaphorase (DH) was immobilized by a cobaltocene-modified poly(allylamine) redox polymer on the electrode surface (DH/Cc-PAA bioelectrode) to achieve effective bioelectrocatalytic NADH regeneration. Since AdhS is a NAD-dependent dehydrogenase, the diaphorase-modified biocathode was used to regenerate NADH to support the conversion from ethyl 4-chloroacetoacetate (COBE) to ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE) catalyzed by AdhS. The addition of methyl tert-butyl ether (MTBE) as an organic phase not only increased the uploading of COBE but also prevented the spontaneous hydrolysis of COBE, extended the lifetime of DH/Cc-PAA bioelectrode, and increased the Faradaic efficiency and the concentration of generated (R)-ethyl-4-cyano-3-hydroxybutyrate ((R)-CHCN). After 10 h of reaction, the highest concentration of (R)-CHCN in the biphasic bioelectrocatalytic system was 25.5 mM with 81.2% enantiomeric excess (eep). The conversion ratio of COBE achieved 85%, which was 8.8 times higher than that achieved with the single-phase system. Besides COBE, two other substrates with aromatic ring structures were also used in this biphasic bioelectrocatalytic system to prepare the corresponding chiral β-hydroxy nitriles. The results indicate that the biphasic bioelectrocatalytic system has the potential to produce a variety of β-hydroxy nitriles with different structures.
Synthesis of Vicinal Dichlorides via Activation of Aliphatic Terminal Epoxides with Triphosgene and Pyridine
Cleveland, Alexander H.,Fronczek, Frank R.,Kartika, Rendy
, p. 3367 - 3377 (2018/03/26)
Herein we report a novel synthetic reaction to convert unactivated terminal aliphatic epoxide to alkyl vicinal dichloride based on triphosgene-pyridine activation. Our methodology is operationally simple and readily tolerated by a broad of scope of substrates as well as protecting groups. Furthermore, these mild conditions generally yield clean reaction mixtures that are free of byproducts upon aqueous workup.
AZAQUINAZOLINE INHIBITORS OF ATYPICAL PROTEIN KINASE C
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Page/Page column 232, (2014/04/17)
The present invention provides a compound of formula (I) or a salt thereof, wherein R7, R8, R9, G, and X are as defined herein. A compound of formula (I) and its salts have a PKC inhibitory activity, and may be used to treat proliferative disorders.
Regioselective conversion of unsymmetrical terminal epoxides into vicinal chlorohydrins using dimethoxyboron chloride
Roy, Chandra D.
, p. 834 - 836 (2007/10/03)
A highly regioselective synthesis of chlorohydrins by chlorinative cleavage of unsymmetrical epoxides utilizing dimethoxyboron chloride is described. Except for styrene oxide, all the terminal epoxides were regioselectively cleaved following a predominantly SN2-type reaction pathway favouring the formation of primary chlorides. In the case of styrene oxide, a benzylic epoxide, (MeO)2BCl transfers the chlorine at the benzylic position, by following an apparent SN1-type mechanism. CSIRO 2006.
1,2-Ferrocenediylazaphosphinines 2: A new class of nucleophilic catalysts for ring-opening of epoxides
Paek, Seung Hwan,Shim, Sang Chul,Cho, Chan Sik,Kim, Tae-Jeong
, p. 849 - 851 (2007/10/03)
1,2-Ferrocenediylazaphosphinines (1a-c) have been successfully employed as a new class of nucleophilic catalysts for ring-opening of a range of epoxides, their catalytic efficiency in terms of regioselectivity as well as chemical yield comparing well with the existing catalysts in the literature. In contrast, low enantiomeric excesses have been obtained from the reactions of meso-epoxides catalyzed by (R)-1.
Demonstration of a phosphazirconocene as a catalyst for the ring opening of epoxides with TMSCI
Wang, Li-Sheng,Hollis, T. Keith
, p. 2543 - 2545 (2007/10/03)
(Matrix presented) In this study, it was demonstrated for the first time that a phosphazirconocene catalyzes the ring opening of epoxides with TMSCI. This reactivity leads to a facile preparation of chlorohydrins. The late transition metal Fe analogue was found to catalyze the reaction at rates and stereoselectivity comparable to those of the Zr complex.
Novel ring-opening of epoxides and oxetanes with POCl3 or PCl3 in the presence of DMAP
Sartillo-Piscil, Fernando,Quintero, Leticia,Villegas, Clarisa,Santacruz-Juárez, Ericka,Anaya De Parrodi, Cecilia
, p. 15 - 17 (2007/10/03)
Efficient synthesis of chlorohydrins by cleavage of oxiranes and oxetanes using POCl3 or PCl3 in the presence of DMAP (4-N,N-dimethylaminopyridine) has been studied.
Bis-chlorodibutyltin oxide as a new reagent for a mild, versatile and regioselective ring-opening of epoxides
Salomon
, p. 65 - 68 (2007/10/03)
A convenient and efficient procedure for the ring-opening of epoxides by means of alcohols and bis-chlorodibutyltin oxide is described. The cleavage of the oxiranes is found to proceed regioselectively under mild reaction conditions. Thus, several haloalkanols, useful intermediates toward biological active molecules, are easily obtained in very good yields.
Palladium- and light-enhanced ring-opening of oxiranes by copper chloride
Muzart, Jacques,Riahi, Abdelkhalek
, p. 323 - 336 (2007/10/02)
The yields of chlorohydrins formed by cleavage of epoxides by CuCl2 is increased in the presence of small amounts of PdCl2(MeCN)2.The conversion drops dramatically on carrying out the reaction in the dark.The regiochemistry of the ring-opening is sensitive to the nature of the substituents.
