4769-73-7Relevant articles and documents
A phosphonium ylide as a visible light organophotoredox catalyst
Toda, Yasunori,Tanaka, Katsumi,Matsuda, Riki,Sakamoto, Tomoyuki,Katsumi, Shiho,Shimizu, Masahiro,Ito, Fuyuki,Suga, Hiroyuki
supporting information, p. 3591 - 3594 (2021/04/14)
A phosphonium ylide-based visible light organophotoredox catalyst has been designed and successfully applied to halohydrin synthesis using trichloroacetonitrile and epoxides. An oxidative quenching cycle by the ylide catalyst was established, which was confirmed by experimental mechanistic studies.
Visible-light-triggered Catalytic Halohydrin Synthesis from Epoxides and Trichloroacetonitrile by Copper and Iron Salts
Toda, Yasunori,Tanaka, Katsumi,Matsuda, Riki,Suga, Hiroyuki
supporting information, p. 1469 - 1471 (2019/12/02)
Preparation of vicinal halohydrins, in which copper or iron chlorides catalyze the ring-opening reaction of epoxides with visible light effectively, is described. The use of trichloroacetonitrile as a halogen source enables catalytic HCl generation under the mild conditions. This method can also be applied to the aziridine ring-opening reaction.
Synthesis, Characterization, and Evaluation of Surface and Thermal Properties and Cytotoxicity of 2-Hydroxy-3-Phenoxypropyl Imidazolium Bola-Type Gemini Amphiphiles
Aggarwal, Rajni,Singh, Sukhprit,Saini, Vedangana,Kaur, Gurcharan
, p. 33 - 46 (2018/10/25)
A library of imidazolium-based gemini cationic bola amphiphiles was synthesized using a regioselective ring-opening reaction of glycidyl phenyl ether with imidazole under solvent-free conditions. The corresponding hexafluorophosphate (PF6?) and tetrafluoroborate (BF4?) counterion-containing amphiphiles were also synthesized and characterized using nuclear magnetic resonance (NMR) and mass spectroscopy. The micellar and interfacial parameters like the critical micelle concentration (CMC), surface pressure at the CMC (Пcmc), surface tension at CMC (γcmc), counterion binding (β), maximum surface excess concentration (Γmax), minimum area per molecule (Amin), standard free energy of micellization (ΔG0mic) and adsorption (ΔG0ads), and Kraft temperature were evaluated using surface tension and conductometry methods in aqueous solution as well as in buffer solution. Dynamic light scattering (DLS) was used to determine the size of the micelles formed in the aqueous solution. Cytotoxicity tests were carried out on the C6 glioma cancerous brain cell line using the MTT assay (3-(4, 5-dimethylthiazole-2-yl)-2, 5-diphenyltetrazolium bromide) to evaluate the IC50 value of all the synthesized amphiphiles. Thermal stability of these amphiphiles was also evaluated using a thermal gravimetric analyzer (TGA). Economic way of synthesis, moderate thermal stability, a low value of CMC, and cytotoxicity of these amphiphiles will inspire new research in the field of nanobiotechnology and pharmaceutical industries.
Trihaloisocyanuric Acid/Triphenylphosphine: An Efficient System for Regioselective Conversion of Epoxides into Vicinal Halohydrins and Vicinal Dihalides under Mild Conditions
De Andrade, Vitor S. C.,De Mattos, Marcio C. S.
, p. 1381 - 1388 (2016/05/19)
A new synthetic method has been developed for the regioselective conversion of epoxides to vicinal chloro-/bromohydrins and vicinal dihalides by reaction with the system trihaloisocyanuric acid/tri?phenylphosphine in acetonitrile under mild and neutral conditions. The reactions proceed smoothly in high yield at room temperature and at reflux, respectively, over a short time.
Highly enantioselective CALB-catalyzed kinetic resolution of building blocks for β-blocker atenolol
Lund, Ingvild T.,B?ckmann, P?l L.,Jacobsen, Elisabeth E.
, p. 7288 - 7292 (2016/10/26)
Both enantiomers of 4-(3-chloro-2-hydroxypropoxy)phenyl)acetamide has been synthesized in 98.5–99% enantiomeric excess by use of lipase B from Candida antarctica as catalyst. The R-alcohol is a building block for the cardioselective β-blocker (S)-atenolol ((S)-2-(4-(2-hydroxy-3-(isopropylamino)propoxy)phenyl)acetamide. Performing kinetic resolutions of 3-chloro-1-phenoxy-2-propanol and 3-bromo-1-phenoxy-2-propanol with vinyl butanoate as acyl donor and the same CALB enzyme, but a different preparation, showed higher E-values than previously reported.
Organocatalytic Regioselective Chlorosilylation of Oxirane Derivatives: Mild and Effective Insertion of Bulky Silyl Chloride by Using 4-Methoxypyridine N-Oxide
Yoshida, Keisuke,Suzuki, Hina,Inoue, Hiroki,Matsui, Kohei,Fujino, Yuta,Kanoko, Yohei,Itatsu, Yukihiro,Takao, Ken-Ichi
, p. 1886 - 1891 (2016/07/06)
The highly regioselective organocatalytic chlorosilylation of oxirane derivatives using bulky silyl reagents such as (tert-butyl)diphenylsilyl chloride (TBDPSCl) or triphenylsilyl chloride (Ph3SiCl) was developed. The reaction was effectively catalyzed with 4-methoxypyridine N-oxide in the presence of sodium sulfate (Na2SO4). Several silylated halohydrins were obtained with complete regioselectivity and the reaction was applied to the synthesis of carvedilol. (Figure presented.) .
Continuous and convergent access to vicinyl amino alcohols
Nobuta, Tomoya,Xiao, Guozhi,Ghislieri, Diego,Gilmore, Kerry,Seeberger, Peter H.
, p. 15133 - 15136 (2015/10/12)
Five active pharmaceutical ingredients (APIs) containing the vicinyl amino alcohol moiety were synthesized using a convergent chemical assembly system. The continuous system is composed of four flow reaction modules: biphasic oxidation, Corey-Chaykovsky epoxidation, phenol alkylation, and epoxide aminolysis. Judicious choice of reagents and module order allowed for two classes of β-amino alcohols, aryl and aryloxy, to be synthesized in good (27-69%) overall yields.
Reinvestigation of a Catalytic, Enantioselective Alkene Dibromination and Chlorohydroxylation
Denmark, Scott E.,Carson, Nessa
supporting information, p. 5728 - 5731 (2015/12/11)
Attempts to reproduce eight, putative, enantioselective dibromination and chlorohydroxylation reactions from oft-cited literature studies are described. The reactions were performed with full fidelity to the original report wherever possible. Analysis of the enantiomeric composition was performed by chiral stationary phase HPLC or SFC (CSP-HPLC or CSP-SFC), as opposed to the original report, which used chiral shift reagent NMR spectroscopy. After careful study, the reported levels of enantioselectivity were found to be incorrect. Possible explanations for the false positive results are discussed.
1,3,2,4-diazadiphosphetidine-based phosphazane oligomers as source of P(III) atom economy reagents: Conversion of epoxides to vic -haloalcohols, vic -dihalides, and alkenes in the presence of halogen sources
Iranpoor, Nasser,Firouzabadi, Habib,Etemadidavan, Elham
, p. 1165 - 1173 (2014/10/16)
1,3,2,4-Diazadiphosphetidines (P1-P3), as easily prepared, stable, and heterogeneous P(III) compounds, were used for the efficient conversion of epoxides to vic-halohydrins, vic-dihalides, or alkenes in the presence of different halogen sources in CH3CN. Of these phosphazanes, P3 is most suitable and contains 4 phosphorous atoms with the advantage of having greater atom economy and its phosphorus oxide byproduct can be easily separated from the reaction mixture by simple filtration. The nitrogen atoms in this molecule can also act as acid scavengers in the reaction.
Solvent-free, efficient, and high regioselective conversion of epoxides to symmetrical and unsymmetrical vic-dihalides using chlorodiphenylphosphine and n-halosuccinimides
Aghapour, Ghasem,Afzali, Asieh
scheme or table, p. 598 - 605 (2011/05/15)
A new method is described for the efficient and high regioselective conversion of epoxides to symmetrical and unsymmetrical vic-dihalides in high yields using chlorodiphenylphosphine and N-halosuccinimides under solvent-free and neutral conditions and at room temperature. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. Copyright Taylor & Francis Group, LLC.
