31230-83-8Relevant articles and documents
Valence isomerization. Synthesis and characterization of cobalt and nickel complexes with non-innocent N2S2 ligand
Kawamoto, Tatsuya,Kuma, Hiro,Kushi, Yoshihiko
, p. 1599 - 1606 (1997)
The reactions of 2-phenylbenzothiazoline with [M(CH3COO)2]·4H2O (M = Co(II) and Ni(II)) afford the complexes [M(phbt)2] (phbt = 2- (phenylmethyleneamino)benzenethiolato) via a ring opening reaction of 2- phenylb
On the mechanism of the copper-mediated C-S bond formation in the intramolecular disproportionation of imine disulfides
Rokob, Tibor Andras,Rulisek, Lubomir,Srogl, Jiri,Revesz, Agnes,Zins, Emilie L.,Schroeder, Detlef
, p. 9968 - 9979 (2011)
The mechanism of the copper-mediated disproportionation of aromatic imine disulfides to benzothiazoles in the gas phase is investigated by experimental and theoretical methods. Application of infrared multiphoton dissociation and hydrogen/deuterium exchange experiments combined with density functional theory (DFT) calculations of the relevant molecular structures and the associated infrared spectra allows the identification of the observed ionic intermediates. The theoretical investigation of the possible reaction pathways supported by collision-induced dissociation experiments provides a consistent mechanistic picture of the reaction catalyzed by a single copper(I) ion. Activation of the substrate proceeds via homolytic sulfur-sulfur bond cleavage, yielding metal complexes in the formal +3 oxidation state; carbon-sulfur coupling and hydrogen-atom transfer complete the transformation to the products. Exploratory studies demonstrate that in the gas phase, the disproportionation of the imine disulfide can also be mediated by other metal ions via different either homo- or heterolytic mechanisms without involving high-valent intermediates.
Surfactant mediated oxygen reuptake in water for green aerobic oxidation: Mass-spectrometric determination of discrete intermediates to correlate oxygen uptake with oxidation efficiency
Parikh, Naisargee,Kumar, Dinesh,Roy, Sudipta Raha,Chakraborti, Asit K.
, p. 1797 - 1799 (2011)
A novel strategy of catalytic green aerobic oxidation by surfactant-mediated oxygen reuptake in water offers a new dimension to the applications of surfactants to look beyond as solubility aids and a conceptual advancement in understanding the role of surfactants in aquatic organic reactions through mass spectrometry guided identification of discrete intermediates.
Orderly cascade of immobilized-enzyme catalysis and photocatalysis for continuous-microflow production of 2-phenylbenzothiazole
Chen, Qiang,Luo, Guang-Sheng,Wang, Yu-Jun
supporting information, p. 7074 - 7083 (2021/09/28)
Green, economic, efficient, and sustainable synthesis of 2-phenylbenzothiazole (2-PBZ)—an important versatile scaffold—remains challenging. Here, for the first time, we propose to cascade immobilized enzyme catalysis and photocatalysis in a continuous-microflow manner to realize the online reuse of the enzyme, eliminate cross-inhibitions between the two-step reaction processes, provide stronger and more uniform illumination, and enhance process efficiency. This novel microflow system required only 4.6 min of the total residence time to achieve >99% product yield, and 93.7% of the total catalytic activity was retained after running for 300 min. This orderly cascaded continuous-flow microreactor system widens the limitations of photo-biocatalytic approaches and provides the potential foundation for the industrial green production of 2-PBZ.
Design, synthesis and evaluation of benzothiazole derivatives as multifunctional agents
Andreotti, Elisa,Baldisserotto, Anna,Balzarini, Jan,Buzzi, Raissa,Dissette, Valeria,Djuidje, Ernestine Nicaise,Liekens, Sandra,Manfredini, Stefano,Sciabica, Sabrina,Serra, Elena,Vertuani, Silvia
, (2020/06/22)
Oxidative stress is the product or aetiology of various multifactorial diseases; on the other hand, the development of multifunctional compounds is a recognized strategy for the control of complex diseases. To this end, a series of benzothiazole derivatives was synthesized and evaluated for their multifunctional effectiveness as antioxidant, sunscreen (filter), antifungal and antiproliferative agents. Compounds were easily synthesized via condensation reaction between 2-aminothiophenols and different benzaldehydes. SAR study, particularly in position 2 and 6 of benzothiazoles, led to the identification of 4g and 4k as very interesting potential compounds for the design of multifunctional drugs. In particular, compound 4g is the best blocker of hERG potassium channels expressed in HEK 293 cells exhibiting 60.32percent inhibition with IC50 = 4.79 μM.
Aerobic Dehydrogenation of N-Heterocycles with Grubbs Catalyst: Its Application to Assisted-Tandem Catalysis to Construct N-Containing Fused Heteroarenes
Kawauchi, Daichi,Noda, Kenta,Komatsu, Yoshiyuki,Yoshida, Kei,Ueda, Hirofumi,Tokuyama, Hidetoshi
supporting information, p. 15793 - 15798 (2020/10/12)
An aerobic dehydrogenation of nitrogen-containing heterocycles catalyzed by Grubbs catalyst is developed. The reaction is applicable to various nitrogen-containing heterocycles. The exceptionally high functional group compatibility of this method was confirmed by the oxidation of an unprotected dihydroindolactam V to indolactam V. Furthermore, by taking advantage of the oxygen-mediated structural change of the Grubbs catalyst, we integrated ring-closing metathesis and subsequent aerobic dehydrogenation to develop the novel assisted-tandem catalysis using molecular oxygen as a chemical trigger. The utility of the assisted-tandem catalysis was demonstrated by the concise synthesis of N-containing fused heteroarenes including a natural antibiotic, pyocyanine.
Peroxide-mediated oxidative coupling of primary alcohols and disulfides: Synthesis of 2-substituted benzothiazoles
Padilha, Nathalia B.,Penteado, Filipe,Salom?o, Maria C.,Lopes, Eric F.,Bettanin, Luana,Hartwig, Daniela,Jacob, Raquel G.,Lenard?o, Eder J.
supporting information, p. 1587 - 1591 (2019/05/21)
A peroxide-mediated protocol for the synthesis of 2-substituted benzothiazoles was developed, starting from bis(o-aminophenyl) disulfides and primary alcohols. Eleven differently 2-substituted benzothiazoles were prepared in moderate to excellent yields using di-tert-butyl peroxide (DTBP) as an oxidant.
Improvement in aluminum complexes bearing a Schiff base in ring-opening polymerization of ε-caprolactone: the synergy of the N,S-Schiff base in a five-membered ring aluminum system
Huang, Ting-Wei,Su, Rou-Rong,Lin, Yi-Chen,Lai, Hsin-Yu,Yang, Chien-Yi,Senadi, Gopal Chandru,Lai, Yi-Chun,Chiang, Michael Y.,Chen, Hsuan-Ying
, p. 15565 - 15573 (2018/11/20)
A series of five-membered ring aluminum complexes bearing thiol-Schiff base ligands were synthesized, and their application in the ring-opening polymerization of ε-caprolactone (CL) was investigated. The complexes exhibited dramatically higher catalytic a
Iminium Catalysis inside a Self-Assembled Supramolecular Capsule: Scope and Mechanistic Studies
Br?uer, Thomas M.,Zhang, Qi,Tiefenbacher, Konrad
supporting information, p. 17500 - 17507 (2017/12/15)
Although iminium catalysis has become an important tool in organic chemistry, its combination with supramolecular host systems has remained largely unexplored. We report the detailed investigations into the first example of iminium catalysis inside a supramolecular host. In the case of 1,4-reductions of α,β-unsaturated aldehydes, catalytic amounts of host are able to increase the enantiomeric excess of the products formed. Several control experiments were performed and provided strong evidence that the modulation of enantiomeric excess of the reaction product indeed stems from a reaction on the inside of the capsule. The origin of the increased enantioselectivity in the capsule was investigated. Furthermore, the substrate and nucleophile scope were studied. Kinetic investigations as well as the kinetic isotope effect measured confirmed that the hydride delivery to the substrate is the rate-determining step inside the capsule. The exploration of benzothiazolidines as alternative hydride sources revealed an unexpected substitution effect of the hydride source itself. The results presented confirm that the noncovalent combination of supramolecular hosts with iminium catalysis is opening up new exciting possibilities to increase enantioselectivity in challenging reactions.
Frustrated Lewis Pair Catalyzed Dehydrogenative Oxidation of Indolines and Other Heterocycles
Maier, Alexander F. G.,Tussing, Sebastian,Schneider, Tobias,Fl?rke, Ulrich,Qu, Zheng -Wang,Grimme, Stefan,Paradies, Jan
supporting information, p. 12219 - 12223 (2016/10/13)
An acceptorless dehydrogenation of heterocycles catalyzed by frustrated Lewis pairs (FLPs) was developed. Oxidation with concomitant liberation of molecular hydrogen proceeded in high to excellent yields for N-protected indolines as well as four other substrate classes. The mechanism of this unprecedented FLP-catalyzed reaction was investigated by mechanistic studies, characterization of reaction intermediates by NMR spectroscopy and X-ray crystal analysis, and by quantum-mechanical calculations. Hydrogen liberation from the ammonium hydridoborate intermediate is the rate-determining step of the oxidation. The addition of a weaker Lewis acid as a hydride shuttle increased the reaction rate by a factor of 2.28 through a second catalytic cycle.
