Search results

Search for "TEMPO" in Full Text gives 174 result(s) in Beilstein Journal of Organic Chemistry.

Metal-free synthesis of phosphinoylchroman-4-ones via a radical phosphinoylation–cyclization cascade mediated by K2S2O8

  • Qiang Liu,
  • Weibang Lu,
  • Guanqun Xie and
  • Xiaoxia Wang

Beilstein J. Org. Chem. 2020, 16, 1974–1982, doi:10.3762/bjoc.16.164

Graphical Abstract
  •  5). When the reaction was conducted in the presence of radical scavengers such as 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO) and butylated hydroxytoluene (BHT), the reactions were completely shut down, which indicated that the reaction proceeds through a radical pathway [37][38][39][40][41]. Also
PDF
Album
Supp Info
Letter
Published 12 Aug 2020

Et3N/DMSO-supported one-pot synthesis of highly fluorescent β-carboline-linked benzothiophenones via sulfur insertion and estimation of the photophysical properties

  • Dharmender Singh,
  • Vipin Kumar and
  • Virender Singh

Beilstein J. Org. Chem. 2020, 16, 1740–1753, doi:10.3762/bjoc.16.146

Graphical Abstract
  • 2-nitrobenzaldehyde (C) could not be achieved with KOH in MeOH or Cs2CO3 in DMSO. To probe the reaction mechanism, a control experiment was conducted with model substrate 1bA in the presence of a radical scavenger (TEMPO) to check the possibility of a radical mechanism vs an electrophilic addition
  • of sulfur [69] (Scheme 7). It was observed that the reaction could not be completed even after 24 h in the presence of TEMPO whereas only 20 min were required for completion under standard conditions. Thus, it is assumed that the reaction proceeds through a radical pathway. Based on our observations
PDF
Album
Supp Info
Full Research Paper
Published 20 Jul 2020

Oxime radicals: generation, properties and application in organic synthesis

  • Igor B. Krylov,
  • Stanislav A. Paveliev,
  • Alexander S. Budnikov and
  • Alexander O. Terent’ev

Beilstein J. Org. Chem. 2020, 16, 1234–1276, doi:10.3762/bjoc.16.107

Graphical Abstract
  • the β-position were transformed into isoxazolines or isoxazoles by oxidative cyclization [114] under the action of TEMPO and K2CO3 (Scheme 23). The presence of aryl substituents at the β-position of the oxime contributed to high yields of the desired products (63a–c, 55–87%), in the presence of only
  • one aryl group in the β-position (R3 = H, R2 = Ar) and further processing of the reaction mixture with atmospheric oxygen, an aromatization occurs with the formation of isoxazoles (64a,b 55–95%). Presumably, the reaction of TEMPO with oxime 62 affords the iminoxyl radical 65 (Scheme 24). 1,5-HAT in
  • the radical 65 gives a C-centered radical 66, which is captured by TEMPO to form intermediate 67. Elimination of TEMPOH leads to a β-unsaturated oxime 68, which could undergo cyclization by ionic or radical mechanisms to give isoxazoline 63 [114][115]. A similar cyclization with the formation of
PDF
Album
Review
Published 05 Jun 2020

Photocatalysis with organic dyes: facile access to reactive intermediates for synthesis

  • Stephanie G. E. Amos,
  • Marion Garreau,
  • Luca Buzzetti and
  • Jerome Waser

Beilstein J. Org. Chem. 2020, 16, 1163–1187, doi:10.3762/bjoc.16.103

Graphical Abstract
  • transformation, the arene is first oxidized by the excited state of the photocatalyst, generating the arene radical cation I. The latter then undergoes a nucleophilic attack of the N-heterocycle, affording the radical adduct II. TEMPO and O2 act as oxidants for the formation of the final aromatic compound via
  • cooperative TEMPO and photoredox catalysis. The SET oxidation of the anion of the β,γ-unsaturated hydrazones 37.1 is mediated by TEMPO+, itself formed by an SET oxidation with the excited state of Mes-Acr-Me+ (OD2). The pyrazolines 37.2 are formed through an intramolecular addition to the alkene, followed by
PDF
Album
Review
Published 29 May 2020

Copper catalysis with redox-active ligands

  • Agnideep Das,
  • Yufeng Ren,
  • Cheriehan Hessin and
  • Marine Desage-El Murr

Beilstein J. Org. Chem. 2020, 16, 858–870, doi:10.3762/bjoc.16.77

Graphical Abstract
  • with TEMPO (2,2,6,6-tetramethyl-1-piperidine N-oxyl) [25] and ABNO (9-azabicyclo[3.3.1]nonane N-oxyl) radicals [26]. Later reports enlarged the synthetic scope of this methodology and provided access to a wide range of synthetically useful building blocks such as substituted heterocycles, fluorinated
PDF
Album
Review
Published 24 Apr 2020

Aldehydes as powerful initiators for photochemical transformations

  • Maria A. Theodoropoulou,
  • Nikolaos F. Nikitas and
  • Christoforos G. Kokotos

Beilstein J. Org. Chem. 2020, 16, 833–857, doi:10.3762/bjoc.16.76

Graphical Abstract
  • Scheme 27b. Even 0.5 equivalents of benzaldehyde were able to promote the reaction. Furthermore, atmospheric oxygen and TEMPO inhibited the reaction. These facts suggest a radical mechanism. A very low yield was observed in the absence of irradiation. No product was detected in the absence of (NH4)2S2O8
PDF
Album
Review
Published 23 Apr 2020

Recent advances in Cu-catalyzed C(sp3)–Si and C(sp3)–B bond formation

  • Balaram S. Takale,
  • Ruchita R. Thakore,
  • Elham Etemadi-Davan and
  • Bruce H. Lipshutz

Beilstein J. Org. Chem. 2020, 16, 691–737, doi:10.3762/bjoc.16.67

Graphical Abstract
  • under mild reaction conditions to yield saturated ketones 410 and 411 in good to excellent yields. Hydrogen isotope labelling showed that water was likely the source of hydrogen since no reaction was observed under anhydrous conditions. By contrast, the addition of either TEMPO and BHT to the reaction
PDF
Album
Review
Published 15 Apr 2020

Cascade trifluoromethylthiolation and cyclization of N-[(3-aryl)propioloyl]indoles

  • Ming-Xi Bi,
  • Shuai Liu,
  • Yangen Huang,
  • Xiu-Hua Xu and
  • Feng-Ling Qing

Beilstein J. Org. Chem. 2020, 16, 657–662, doi:10.3762/bjoc.16.62

Graphical Abstract
  • reaction. In order to gain insight into the reaction mechanism, the radical scavenger 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) was added to the standard reactions of 1a and 3b, respectively. The desired product 2a was not formed and only trace of 4b was detected (see the Supporting Information File 1
  • ), which suggested that the radical process was probably involved in these transformations. Notably, no TEMPO-trapped product was detected by 19F NMR spectra of the crude reaction mixtures. On the basis of these results and literature studies [21][23][42][43][44][45][46][47], a plausible reaction mechanism
PDF
Album
Supp Info
Letter
Published 08 Apr 2020

KOt-Bu-promoted selective ring-opening N-alkylation of 2-oxazolines to access 2-aminoethyl acetates and N-substituted thiazolidinones

  • Qiao Lin,
  • Shiling Zhang and
  • Bin Li

Beilstein J. Org. Chem. 2020, 16, 492–501, doi:10.3762/bjoc.16.44

Graphical Abstract
  • involved in the reaction. Excellent yields of products 3a or 5a were obtained in the presence of the radical scavengers (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO), stilbene, or butylated hydroxytoluene (BHT) in the reaction of benzyl bromide with 2-methyl-2-oxazoline or 2-(methylthio)-4,5
PDF
Album
Supp Info
Full Research Paper
Published 25 Mar 2020

Recent advances in photocatalyzed reactions using well-defined copper(I) complexes

  • Mingbing Zhong,
  • Xavier Pannecoucke,
  • Philippe Jubault and
  • Thomas Poisson

Beilstein J. Org. Chem. 2020, 16, 451–481, doi:10.3762/bjoc.16.42

Graphical Abstract
  • benzyl NHP esters. The products were obtained in good yields. The functional group tolerance of the process was excellent and was further demonstrated in the course of a robustness screen. Supported by mechanistic experiments, including UV–vis analysis, crossover studies, trapping with TEMPO, and the use
PDF
Album
Review
Published 23 Mar 2020

Visible-light-induced addition of carboxymethanide to styrene from monochloroacetic acid

  • Kaj M. van Vliet,
  • Nicole S. van Leeuwen,
  • Albert M. Brouwer and
  • Bas de Bruin

Beilstein J. Org. Chem. 2020, 16, 398–408, doi:10.3762/bjoc.16.38

Graphical Abstract
  • catalysts used in this reaction. In an attempt to trap one of the radical intermediates with TEMPO, we observed a compound indicating the generation of a chloromethyl radical. Keywords: ATRA; catalysis; chloroacetic acid; lactone; photoredox; Introduction Monochloroacetic acid is an industrially important
  • trapping the radical by replacing styrene with TEMPO (2,2,6,6-tetramethylpiperidin-1-yl)oxyl). However, GC–MS analysis indicated full conversion of TEMPO to the adduct resulting from a radical coupling between a cyanomethanide radical and TEMPO (Scheme 3) for the highly reducing [Ir(ppy)3] (−1.73 V vs SCE
  • . Additionally, to provide evidence for oxidative quenching, we tried trapping the carboxymethanide radical with TEMPO in benzene. We were surprised to see that instead we trapped the chloromethyl radical (Scheme 7) which was not expected in the absence of any base and with a relatively poorly oxidizing
PDF
Album
Supp Info
Full Research Paper
Published 16 Mar 2020

Room-temperature Pd/Ag direct arylation enabled by a radical pathway

  • Amy L. Mayhugh and
  • Christine K. Luscombe

Beilstein J. Org. Chem. 2020, 16, 384–390, doi:10.3762/bjoc.16.36

Graphical Abstract
  • suppressed by the addition of TEMPO and BHT. Moreover, Ph-BHT was observed by GC–MS when BHT was added. Similar to the polymerization trials, coupling was inhibited when the standard conditions were run in the dark. Both the Ph-BHT adduct and continued poor reactivity in the dark provides growing evidence
PDF
Album
Supp Info
Full Research Paper
Published 13 Mar 2020

Copper-promoted/copper-catalyzed trifluoromethylselenolation reactions

  • Clément Ghiazza and
  • Anis Tlili

Beilstein J. Org. Chem. 2020, 16, 305–316, doi:10.3762/bjoc.16.30

Graphical Abstract
  • of TEMPO, and thus a radical pathway was considered as less likely. Contrarily to the precedent mechanism, the authors proposed a 1,4-addition of −SeCF3, and a bromide elimination to occur. The synthesis of trifluoromethylseleno esters was also explored by the group of Weng from readily available
PDF
Album
Review
Published 03 Mar 2020

Construction of trisubstituted chromone skeletons carrying electron-withdrawing groups via PhIO-mediated dehydrogenation and its application to the synthesis of frutinone A

  • Qiao Li,
  • Chen Zhuang,
  • Donghua Wang,
  • Wei Zhang,
  • Rongxuan Jia,
  • Fengxia Sun,
  • Yilin Zhang and
  • Yunfei Du

Beilstein J. Org. Chem. 2019, 15, 2958–2965, doi:10.3762/bjoc.15.291

Graphical Abstract
  • absence of a carbonyl group in its chemical structure [85]. Control experiments were designed and conducted to elucidate the reaction mechanism of this transformation. When 3 equiv of TEMPO, a radical-trapping reagent, were added to the reaction mixture, product 2a was obtained in 55% yield (Scheme 3
PDF
Album
Supp Info
Letter
Published 12 Dec 2019

A review of asymmetric synthetic organic electrochemistry and electrocatalysis: concepts, applications, recent developments and future directions

  • Munmun Ghosh,
  • Valmik S. Shinde and
  • Magnus Rueping

Beilstein J. Org. Chem. 2019, 15, 2710–2746, doi:10.3762/bjoc.15.264

Graphical Abstract
  • for the electrocatalytic oxidative coupling of 42 using constant potential electrolysis of the substrates on a graphite felt electrode modified with TEMPO in the presence of (−)-sparteine 43. The electrolysis resulted in (S)-binaphthyl type dimers 44 with excellent yield and enantiomeric excess
  • (Scheme 18) [49]. Later, the same group explored another application of TEMPO-modified graphite felt electrodes for enantioselective electrocatalytic oxidation of racemic secondary alcohols 45 and 48 (Scheme 19). (S)-Isomers of alcohol 48 possessing a chiral center at α-position to the hydroxy group were
  • oxidized to the corresponding ketones 49 whereas (R)-50 remained unreacted on a TEMPO-modified graphite felt electrode in the presence of (−)-sparteine. Enantiopurity of remaining alcohols were found to be more than 99% in all cases [50]. As a result of their study towards suitable modification of graphite
PDF
Album
Review
Published 13 Nov 2019

α-Photooxygenation of chiral aldehydes with singlet oxygen

  • Dominika J. Walaszek,
  • Magdalena Jawiczuk,
  • Jakub Durka,
  • Olga Drapała and
  • Dorota Gryko

Beilstein J. Org. Chem. 2019, 15, 2076–2084, doi:10.3762/bjoc.15.205

Graphical Abstract
  • ], TEMPO [4], or benzoyl peroxide [5][6][7][8]. Therefore, the use of environmentally friendly reagents instead is highly desirable. Along this line, singlet oxygen by being easily photochemically generated from triplet oxygen in the presence of organic dyes seems promising. Despite its high reactivity and
PDF
Album
Supp Info
Full Research Paper
Published 30 Aug 2019

Metal-free mechanochemical oxidations in Ertalyte® jars

  • Andrea Porcheddu,
  • Francesco Delogu,
  • Lidia De Luca,
  • Claudia Fattuoni and
  • Evelina Colacino

Beilstein J. Org. Chem. 2019, 15, 1786–1794, doi:10.3762/bjoc.15.172

Graphical Abstract
  • l’Ecole Normale, 34296 Montpellier, Cedex 5, France 10.3762/bjoc.15.172 Abstract Aimed at eliminating or at least significantly reducing the use of solvents, sodium hypochlorite pentahydrate crystals (NaOCl·5H2O) in the presence of a catalytic amount of a nitrosyl radical (TEMPO or AZADO) have been
  • a mechanochemical process. Keywords: AZADO; Ertalyte®; green chemistry; mechanochemistry; NaOCl·5H2O; selective oxidation; TEMPO; Introduction The conversion of primary and secondary alcohols to the corresponding carbonyl compounds (aldehydes and ketones, respectively) is of such importance in
  • the atom efficiency [4][5]. The discovery of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl, commonly known as TEMPO by Lebedev and Kazarnowskii in 1960 has been hailed as a significant breakthrough in the field of redox reactions, allowing the fast and selective oxidation of alcohols to the related carbonyl
PDF
Album
Supp Info
Full Research Paper
Published 25 Jul 2019

Recent advances on the transition-metal-catalyzed synthesis of imidazopyridines: an updated coverage

  • Gagandeep Kour Reen,
  • Ashok Kumar and
  • Pratibha Sharma

Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165

Graphical Abstract
  • aliphatic alkynes gave an optimal yield of the final product in the range of 50–78%. Successful formation of the product on application of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO: a radical scavenger) has nullified the probability of radical pathway. It was thought to be initiated by the coordination of
  • the formation of radical intermediates, as use of TEMPO inhibited intramolecular C(sp3)–H amination of imine species. Aerial oxidation of the Cu(I) species bonded to the N-atom of pyridine and imine 39 resulted in Cu(II) superoxo radical intermediate 40. This was followed by intramolecular hydrogen
  • the desired product. The reaction with secondary amines 35a also resulted in a trace of the final product (Scheme 38). The use of TEMPO (a radical scavenger) has shown that the reaction might proceed through a radical pathway as depicted in Scheme 39. In the presence of TEMPO the desired product was
PDF
Album
Review
Published 19 Jul 2019

Photochemical generation of the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radical from caged nitroxides by near-infrared two-photon irradiation and its cytocidal effect on lung cancer cells

  • Ayato Yamada,
  • Manabu Abe,
  • Yoshinobu Nishimura,
  • Shoji Ishizaka,
  • Masashi Namba,
  • Taku Nakashima,
  • Kiyofumi Shimoji and
  • Noboru Hattori

Beilstein J. Org. Chem. 2019, 15, 863–873, doi:10.3762/bjoc.15.84

Graphical Abstract
  • character, 2,2,6,6-tetramethyl-1-(1-(2-(4-nitrophenyl)benzofuran-6-yl)ethoxy)piperidine (2a) and its regioisomer 2b, were designed and synthesized. The one-photon (OP) (365 ± 10 nm) and TP (710–760 nm) triggered release (i.e., uncaging) of the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radical under air
  • atmosphere were discovered. The quantum yields for the release of the TEMPO radical were 2.5% (2a) and 0.8% (2b) in benzene at ≈1% conversion of 2, and 13.1% (2a) and 12.8% (2b) in DMSO at ≈1% conversion of 2. The TP uncaging efficiencies were determined to be 1.1 GM at 740 nm for 2a and 0.22 GM at 730 nm
  • approach for investigating the role of redox-active nitroxides in mediating oxidative stress in organisms [27][28][29][30][31][32]. In 1997, Scaiano and co-workers reported the triplet-xanthone sensitized generation of the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radical from alkoxyamine 1 under
PDF
Album
Supp Info
Full Research Paper
Published 10 Apr 2019

Synthesis and biological investigation of (+)-3-hydroxymethylartemisinin

  • Toni Smeilus,
  • Farnoush Mousavizadeh,
  • Johannes Krieger,
  • Xingzhao Tu,
  • Marcel Kaiser and
  • Athanassios Giannis

Beilstein J. Org. Chem. 2019, 15, 567–570, doi:10.3762/bjoc.15.51

Graphical Abstract
  • the propargylic moiety with Red-Al. BAIB/TEMPO oxidation of this alcohol gave ketone 7. By a Reformatsky reaction of 7 using Zn/ethyl bromoacetate derivative 8 was obtained, which was subjected to a thermal (190 °C, toluene) intramolecular Diels–Alder reaction resulting in the formation of the β
  • % yield, starting from aldehyde 3 and alkyne 4. Reaction conditions: a) alkyne 4, n-BuLi, THF, −78 °C to rt, 16 h, 86%; b) Red-Al, THF, 0 °C, 10 min, 96%; c) BAIB, TEMPO, DCM, rt, 16 h, 92%; d) BrCH2CO2Et, Zn, toluene, reflux, 30 min, 93%. Red-Al = sodium bis(2-methoxyethoxy)aluminum dihydride, BAIB
  • = (diacetoxyiodo)benzene, TEMPO = (2,2,6,6-tetramethylpiperidin-1-yl)oxyl. Synthesis of (+)-3-hydroxymethyl-9-desmethylartemisinin (16), starting from Diels–Alder derivatives 9 and 10. Reaction conditions: a) toluene, 190 °C, 24 h, 84% (dr 9:10:11 = 1.74:0.38:0.24); b) Martin sulfurane, DCM, 0 °C, 10 min, 97% [(E
PDF
Album
Supp Info
Full Research Paper
Published 27 Feb 2019

Convergent synthesis of the pentasaccharide repeating unit of the biofilms produced by Klebsiella pneumoniae

  • Arin Gucchait,
  • Angana Ghosh and
  • Anup Kumar Misra

Beilstein J. Org. Chem. 2019, 15, 431–436, doi:10.3762/bjoc.15.37

Graphical Abstract
  • unit of biofilms produced by Klebsiella pneumoniae, has been synthesized using a stereoselective [2 + 3] convergent glycosylation strategy. The β-D-mannosidic moiety has been synthesized using a D-mannose-derived thioglycoside by a two-step activation process. Late stage TEMPO-mediated oxidation of the
  • yield with excellent stereoselectivity. The noteworthy features of the synthetic strategy are (a) incorporation of a β-D-mannosidic linkage and (b) late stage TEMPO-mediated oxidation of the primary hydroxy group into a carboxylic group after completion of glycosylations. The starting compound 2
  • the presence of TMSOTf [35] furnished target pentasaccharide derivative 20 in 70% yield (Scheme 4). Removal of the benzoyl group from compound 20 using sodium methoxide [24] followed by TEMPO-mediated oxidation [39] of the hydroxy group to a carboxylic group using sodium hypochlorite under biphasic
PDF
Album
Supp Info
Full Research Paper
Published 13 Feb 2019

Oxidative radical ring-opening/cyclization of cyclopropane derivatives

  • Yu Liu,
  • Qiao-Lin Wang,
  • Zan Chen,
  • Cong-Shan Zhou,
  • Bi-Quan Xiong,
  • Pan-Liang Zhang,
  • Chang-An Yang and
  • Quan Zhou

Beilstein J. Org. Chem. 2019, 15, 256–278, doi:10.3762/bjoc.15.23

Graphical Abstract
  • naphthaldehyde 33 was obtained in 61% yield (Scheme 9, reaction b). Furthermore, the product 31a could also be transformed to the CF3-substituted epoxide 34 in the presence of 2 equiv m-CPBA (m-chloroperbenzoic acid) (Scheme 9, reaction c). A radical-trapping experiment was conducted with the addition of TEMPO
  • cyclization under transition-metal free conditions. With the addition of a radical scavenger such as TEMPO or BHT, the reaction was suppressed remarkably. In the same year, Dai’s group also reported the ring-opening-initiated tandem cyclization of cyclopropanols 91 with acrylamides 122 or 2-isocyanobiphenyls
PDF
Album
Review
Published 28 Jan 2019

Synthesis of nonracemic hydroxyglutamic acids

  • Dorota G. Piotrowska,
  • Iwona E. Głowacka,
  • Andrzej E. Wróblewski and
  • Liwia Lubowiecka

Beilstein J. Org. Chem. 2019, 15, 236–255, doi:10.3762/bjoc.15.22

Graphical Abstract
  • sequence. Reagents and conditions: a) (CF3CH2O)2P(O)CH2COOMe, KHMDS, 18-crown-6, THF; b) PTSA, MeOH; c) NaOCl, TEMPO, KBr, NaHCO3, water/acetone; d) 3 M HCl, 80 °C. Synthesis of the orthogonally protected (2S,3R)-2 from a chiral aziridine. Reagents and conditions: a) LiHMDS, AcOt-Bu, THF; b) NaBH4, iPrOH
PDF
Album
Review
Published 25 Jan 2019

Copper(I)-catalyzed tandem reaction: synthesis of 1,4-disubstituted 1,2,3-triazoles from alkyl diacyl peroxides, azidotrimethylsilane, and alkynes

  • Muhammad Israr,
  • Changqing Ye,
  • Munira Taj Muhammad,
  • Yajun Li and
  • Hongli Bao

Beilstein J. Org. Chem. 2018, 14, 2916–2922, doi:10.3762/bjoc.14.270

Graphical Abstract
  • trapping reagent (tetramethylpiperdinyloxy, TEMPO) [38][39] to the standard reaction system, no product 3a was obtained; only the radical trapped product 4 was detected by GC–MS (Scheme 4a). To further investigate this phenomenon, we synthesized a substrate bearing a cyclopropylmethyl moiety, diacyl
PDF
Album
Supp Info
Full Research Paper
Published 23 Nov 2018

Synthesis of aryl sulfides via radical–radical cross coupling of electron-rich arenes using visible light photoredox catalysis

  • Amrita Das,
  • Mitasree Maity,
  • Simon Malcherek,
  • Burkhard König and
  • Julia Rehbein

Beilstein J. Org. Chem. 2018, 14, 2520–2528, doi:10.3762/bjoc.14.228

Graphical Abstract
  • in Scheme 4. Two equivalents of 2,2,6,6-tetramethylpiperidyl-1-oxyl (TEMPO), a radical scavenger were added to 1,2,4-trimethoxybenzene (Scheme 4a), in the presence of [Ir(dF(CF3)ppy)2(dtbpy)]PF6, ammonium thiosulfate and 455 nm LED irradiation. The reaction mixture was analyzed by mass spectrometry
  • , which showed the molecular ion indicating the formation of the proposed TEMPO adduct with the arene radical intermediate. Also, when diphenyl disulfide was irradiated with TEMPO in the presence and absence of the photocatalyst, (Scheme 4b and Scheme 4c) the adduct 2,2,6,6-tetramethyl-1-((phenylthio)oxy
  • )piperidine was obtained in both cases. See Supporting Information File 1 for the HRMS analysis of the TEMPO adduct. These radical trapping experiments show that initially a radical cation of the arene is formed by the excited photocatalyst, which then is trapped by the radical scavenger TEMPO. S–S bond
PDF
Album
Supp Info
Full Research Paper
Published 27 Sep 2018
Other Beilstein-Institut Open Science Activities