A novel methodology for the efficient synthesis of 3-monohalooxindoles by acidolysis of 3-phosphate-substituted oxindoles with haloid acids

• Li Liu,
• Yue Li,
• Tiao Huang,
• Dulin Kong and
• Mingshu Wu

Beilstein J. Org. Chem. 2021, 17, 2321–2328, doi:10.3762/bjoc.17.150

• disclosed the application of N-fluorobenzenesulfonimide (NFSI) and NBS (N-bromosuccinimide), respectively, as the halogen sources, with diazoacetamide under catalyst-free conditions via a carbene pathway, which constructed 3-fluorooxindoles and 3-bromooxindoles (Scheme 1, reaction 1) [20][21]. Then, the

Chemical syntheses and salient features of azulene-containing homo- and copolymers

• Vijayendra S. Shetti

Beilstein J. Org. Chem. 2021, 17, 2164–2185, doi:10.3762/bjoc.17.139

• due to the formation of dehydropolyazulene via oxidative aromatization. In 2003, Lai and co-workers [20] synthesized 1,3-polyazulene 5 from azulene in two steps as shown in Scheme 3. First, azulene (1) was dibrominated at the 1,3-positions by treatment with N-bromosuccinimide (NBS) and the consequent

Manganese/bipyridine-catalyzed non-directed C(sp³)–H bromination using NBS and TMSN₃

• Kumar Sneh,
• Takeru Torigoe and
• Yoichiro Kuninobu

Beilstein J. Org. Chem. 2021, 17, 885–890, doi:10.3762/bjoc.17.74

• Kasugakoen, Kasuga-shi, Fukuoka 816-8580, Japan 10.3762/bjoc.17.74 Abstract A Mn(II)/bipyridine-catalyzed bromination reaction of unactivated aliphatic C(sp3)−H bonds has been developed using N-bromosuccinimide (NBS) as the brominating reagent. The reaction proceeded in moderate-to-good yield, even on a

• benzylic positions of a wide range of substrates. The manganese catalyst, brominating agent, and additives are commercially available, and the reaction can be achieved by simply mixing these reagents with the substrate. Results and Discussion The reaction of isoamyl alcohol derivative 1a with N

• -bromosuccinimide (NBS) and TMSN3 in the presence of a catalytic amount of Mn(OAc)2 and bipyridine (bpy) in 1,2-dichloroethane (DCE) at 60 °C for 18 h gave C(sp3)–H brominated product 2a in 10% yield (Table 1, entry 1). Although the yield of 2a did not increase when performing the reaction in acetonitrile (Table 1

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

• Shivani Gulati,
• Stephy Elza John and
• Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

Total synthesis of decarboxyaltenusin

• Lucas Warmuth,
• Aaron Weiß,
• Marco Reinhardt,
• Anna Meschkov,
• Ute Schepers and
• Joachim Podlech

Beilstein J. Org. Chem. 2021, 17, 224–228, doi:10.3762/bjoc.17.22

• protected with tert-butyldimethylsilyl chloride in the presence of 4-(dimethylamino)pyridine (DMAP) and imidazole (Scheme 2) according to a published procedure [20]. The thus obtained bis(silylether) 3 was then brominated with N-bromosuccinimide (NBS), where the utilization of acetonitrile as solvent [21

Synthesis of imidazo[1,5-a]pyridines via cyclocondensation of 2-(aminomethyl)pyridines with electrophilically activated nitroalkanes

• Dmitrii A. Aksenov,
• Nikolai A. Arutiunov,
• Vladimir V. Maliuga,
• Alexander V. Aksenov and
• Michael Rubin

Beilstein J. Org. Chem. 2020, 16, 2903–2910, doi:10.3762/bjoc.16.239

• -(bromomethyl)quinoline (21c) was prepared from commercially available 6-bromo-2-methylquinoline (22c, via radical bromination in the presence of NBS and dibenzoyl peroxide [51]. To this end, the methylquinoline 22c (3.33 g, 15 mmol) was dissolved in carbon tetrachloride (30 mL), and N-bromosuccinimide (2.94 g

Synthesis and characterization of S,N-heterotetracenes

• Astrid Vogt,
• Florian Henne,
• Christoph Wetzel,
• Elena Mena-Osteritz and
• Peter Bäuerle

Beilstein J. Org. Chem. 2020, 16, 2636–2644, doi:10.3762/bjoc.16.214

• TIPS-protected thienopyrrole 29 in 92% yield which was further brominated with N-bromosuccinimide (NBS) to dibrominated thienopyrrole 30 in 99% yield. Pd-catalyzed Neghishi-type coupling of 30 with 3-bromo-2-thienylzinc chloride (6) resulted in thienyl-substituted thienopyrrole 31 in moderate 37% yield

Synthetic approaches to bowl-shaped π-conjugated sumanene and its congeners

• Shakeel Alvi and
• Rashid Ali

Beilstein J. Org. Chem. 2020, 16, 2212–2259, doi:10.3762/bjoc.16.186

• -tribromomethyltriphenylene (8) using N-bromosuccinimide (NBS) in the presence of AIBN in CCl4. To their surprise, when compound 8 was subjected to FVP at around 850 °C temperature, only mono- and dibridged compounds (7 and 9) were isolated in overall 20% yield in (13:87) ratio. The structure of the dibridged compound 9 was

Synthesis of novel multifunctional carbazole-based molecules and their thermal, electrochemical and optical properties

• Nuray Altinolcek,
• Ahmet Battal,
• Mustafa Tavasli,
• William J. Peveler,
• Holly A. Yu and
• Peter J. Skabara

Beilstein J. Org. Chem. 2020, 16, 1066–1074, doi:10.3762/bjoc.16.93

• . Carbazole (1) was first brominated with N-bromosuccinimide in dimethylformamide [32][33]. This gave a mixture of mono- and dibromo products 2 and 3. Upon crystallisation 3-bromocarbazole (2) was obtained as white crystals in good yield. 3-Bromocarbazole (2) was then alkylated with 1-bromohexane in 50

• instrument. 3-Bromocarbazole (2): 2 was synthesised as reported previously [32][33]. A solution of N-bromosuccinimide (1.1 g, 5.98 mmol) in dimethylformamide was added dropwise to a solution of carbazole (1, 1 g, 5.96 mmol) in dimethylformamide (15 mL) at 0 °C. The reaction mixture was then stirred at room

Towards triptycene functionalization and triptycene-linked porphyrin arrays

• Gemma M. Locke,
• Keith J. Flanagan and
• Mathias O. Senge

Beilstein J. Org. Chem. 2020, 16, 763–777, doi:10.3762/bjoc.16.70

• dissolved in CHCl3 (150 mL) and degassed for 30 minutes. At 0 °C, N-bromosuccinimide (34 mg, 0.19 mmol) and pyridine (0.1 mL) were added. The reaction was stirred at room temperature for three hours. The progress of the reaction was monitored by TLC and once all starting material had been consumed the

Synthesis of organic liquid crystals containing selectively fluorinated cyclopropanes

• Zeguo Fang,
• Nawaf Al-Maharik,
• Peer Kirsch,
• Matthias Bremer,
• Alexandra M. Z. Slawin and
• David O’Hagan

Beilstein J. Org. Chem. 2020, 16, 674–680, doi:10.3762/bjoc.16.65

• . The synthesis of trifluorocyclopropane 9 is shown in Scheme 2. Compound 9 was prepared through bromofluorination of 12, followed by base-induced HBr elimination [15], and then difluorocarbene addition to generate 9. The starting olefin 12 was exposed to an excess of N-bromosuccinimide (NBS) and HF·Py

Synthesis and characterization of bis(4-amino-2-bromo-6-methoxy)azobenzene derivatives

• David Martínez-López,
• Amirhossein Babalhavaeji,
• Diego Sampedro and
• G. Andrew Woolley

Beilstein J. Org. Chem. 2019, 15, 3000–3008, doi:10.3762/bjoc.15.296

• -morpholinophenyl)diazene (4): (E)-1,2-Bis(2-methoxy-4-morpholinophenyl)diazene (9, 30 mg, 0.07 mmol) was dissolved in DCM. To this solution, palladium acetate (1.6 mg, 0.007 mmol) was added, and the resulting mixture was stirred for 15 minutes. Then, N-bromosuccinimide (28.6 mg, 0.16 mmol) was added to the

• was stirred for 15 minutes. Then, N-bromosuccinimide (22 mg, 0.1 mmol) was added to the reaction. The reaction mixture was stirred for additional 30 minutes until completion. The solvent was evaporated under reduced pressure and the resulting oil was purified by column chromatography using hexane

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

• also be realized by DDQ-mediated dehydrogenation of chromanones under heating in dioxane (Scheme 1b) [3][59][60]. In 2005, Yang and co-workers reported that chromones could be formed by microwave irradiation of the corresponding chromanone reactants and N-bromosuccinimide (NBS) in the presence of a

An improved, scalable synthesis of Notum inhibitor LP-922056 using 1-chloro-1,2-benziodoxol-3-one as a superior electrophilic chlorinating agent

• Nicky J. Willis,
• Elliott D. Bayle,
• George Papageorgiou,
• David Steadman,
• Benjamin N. Atkinson,
• William Mahy and
• Paul V. Fish

Beilstein J. Org. Chem. 2019, 15, 2790–2797, doi:10.3762/bjoc.15.271

• functionalised for the introduction of the C7-cyclopropyl group, the C6-chlorine atom and elaboration of the thioacetic acid moiety at C4. Electrophilic bromination at C7 with N-bromosuccinimide gave 5 as the major regioisomer reproducibly on 100 mmol scale in modest yield (41–48%). This proved to be the least

• . Yields are the ranges obtained from repeated reactions. DMF, N,N-dimethylformamide; NBS, N-bromosuccinimide; THF, tetrahydrofuran. Chlorination of 6 with N-chlorosuccinimide (NCS). Reagents and conditions: (a) NCS (1.2 equiv), AcOH, 55 °C, 7 h, 15–32%. Improved synthesis of 5. Reagents and conditions: (a

Mono- and bithiophene-substituted diarylethene photoswitches with emissive open or closed forms

• A. Lennart Schleper,
• Mariano L. Bossi,
• Vladimir N. Belov and
• Stefan W. Hell

Beilstein J. Org. Chem. 2019, 15, 2344–2354, doi:10.3762/bjoc.15.227

• esters 9 and 12 (bpy – 4,4’-di-tert-butyl-2,2’-dipyridine; COD – cycloocta-1,5-diene; NBS – N-bromosuccinimide, DCM – dichloromethane). Photoswitchable diarylethenes AsTh1, SyTh1, AsTh2, SyTh2, AsOTh1, SyOTh1, AsOTh2, and SyOTh2 synthesized via a Suzuki–Miyaura coupling. Conditions: 60 °C, argon

Synthesis, enantioseparation and photophysical properties of planar-chiral pillar[5]arene derivatives bearing fluorophore fragments

• Guojuan Li,
• Chunying Fan,
• Guo Cheng,
• Wanhua Wu and
• Cheng Yang

Beilstein J. Org. Chem. 2019, 15, 1601–1611, doi:10.3762/bjoc.15.164

• %; ii) N-bromosuccinimide, chloroform, 60 °C, yield: 87%; iii) (4-hydroxyphenyl)boronic acid, Pd(PPh3)4, K2CO3, CsF, toluene/THF/H2O, reflux, 8 h, yield: 70%; iv) K2CO3, 1,5-dibromopentane, acetone, 80 °C, yield: 67%; v) NaN3, DMF, yield: 84%; vi) paraformaldehyde, BF3·OEt2, 1,2-dichloroethane, yield

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

• different amount of NBS (N-bromosuccinimide). The corresponding CF3-substituted naphthalene 32 could be obtained in 69% yield when the product 31a was oxidized by 3 equiv of NBS (Scheme 9, reaction a). When the amount of NBS was increased to 6 equiv under identical conditions, the CF3-substituted

Enhanced single-isomer separation and pseudoenantiomer resolution of new primary rim heterobifunctionalized α-cyclodextrin derivatives

• Iveta Tichá,
• Gábor Benkovics,
• Milo Malanga and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2018, 14, 2829–2837, doi:10.3762/bjoc.14.261

• ). On one hand, a direct bromination of α-CD was performed under Vilsmeier/Haack conditions (reaction 3, Scheme 2) with N-bromosuccinimide (NBS) and Ph3P in N,N-dimethylformamide (DMF). Previous studies have shown that this reaction is highly regioselective for the primary rim of CD [28]. After a fast

A pyridinium/anilinium [2]catenane that operates as an acid–base driven optical switch

• Sarah J. Vella and
• Stephen J. Loeb

Beilstein J. Org. Chem. 2018, 14, 1908–1916, doi:10.3762/bjoc.14.165

• molecular switching previously observed for analogous [2]rotaxanes. Experimental General comments 4-Bromobenzyl bromide, 4-bromoaniline, 4-pyridylboronic acid, 1,3-dichlorobenzene, p-tolylmagnesium bromide, n-butyllithium and N-bromosuccinimide were purchased from Aldrich and used as received. Benzoyl

β-Hydroxy sulfides and their syntheses

• Mokgethwa B. Marakalala,
• Edwin M. Mmutlane and
• Henok H. Kinfe

Beilstein J. Org. Chem. 2018, 14, 1668–1692, doi:10.3762/bjoc.14.143

• . In addition to its environmental benignity and ease of handling, the ionic liquid was reported to be reusable without any loss of activity after five runs. Another efficient catalyst for the synthesis of β-hydroxy sulfides is N-bromosuccinimide (NBS), as reported by Rostami and Jafari [28]. Various

• conditions. N-Bromosuccinimide-catalyzed ring opening of epoxides. LiNTf2-mediated epoxide opening by thiophenol. Asymmetric ring-opening of cyclohexene oxide with various thiols catalyzed by zinc L-tartrate. Catalytic asymmetric ring opening of symmetrical epoxides with t-BuSH catalyzed by (R)-GaLB (43

One hundred years of benzotropone chemistry

• Arif Dastan,
• Haydar Kilic and
• Nurullah Saracoglu

Beilstein J. Org. Chem. 2018, 14, 1120–1180, doi:10.3762/bjoc.14.98

• dehydrogenation using N-bromosuccinimide, and its properties were compared with those of benzotropolone 241A (Scheme 50) [178]. The benzotropolone 174 could also be prepared from diester 301 in a similar way (Scheme 50) [179]. The simultaneous hydrolysis and decarboxylation of benzotropolone-diester 304 to 174

Latest development in the synthesis of ursodeoxycholic acid (UDCA): a critical review

• Fabio Tonin and
• Isabel W. C. E. Arends

Beilstein J. Org. Chem. 2018, 14, 470–483, doi:10.3762/bjoc.14.33

• of the 7-OH group. Chemically, the 7α-OH group of CDCA, obtained by dehydroxylation of CA (see above “C12 dehydroxylation”), is selectively oxidized in the presence of sodium bromate [59] (yield 88%), N-bromosuccinimide [13][15] (ungiven yield) or 1-hydroxy-1,2-benziodoxol-3(1H)-one 1-oxide [60

Palladium-catalyzed ortho-halogenations of acetanilides with N-halosuccinimides via direct sp² C–H bond activation in ball mills

• Zi Liu,
• Hui Xu and
• Guan-Wu Wang

Beilstein J. Org. Chem. 2018, 14, 430–435, doi:10.3762/bjoc.14.31

• (OTs)2 in the presence of TsOH. It was intriguing to find that N-bromosuccinimide (NBS) and N-chlorosuccinimide (NCS) could also be used as reaction partners to react with the representative acetanilide 1a under identical ball-milling conditions. The corresponding ortho-brominated and ortho-chlorinated

• ][24][25][26][27][28]. A few mechanochemical ortho-C–H bond activation reactions under the catalysis of rhodium and palladium salts have been reported [29][30][31][32][33][34][35][36][37][38]. Hernández and Bolm reported the rhodium-catalyzed bromination and iodination of 2-phenylpyridine using N

• -bromosuccinimide (NBS) and N-iodosuccinimide (NIS), respectively, as the halogen source [30]. However, the mechanochemical ortho-halogenation using the cheaper palladium catalysts has not been reported yet. In continuing our interest in mechanochemistry [21][22][39][40][41] and C–H activation reactions [42][43][44

One-pot preparation of 4-aryl-3-bromocoumarins from 4-aryl-2-propynoic acids with diaryliodonium salts, TBAB, and Na₂S₂O₈

• Teppei Sasaki,
• Katsuhiko Moriyama and
• Hideo Togo

Beilstein J. Org. Chem. 2018, 14, 345–353, doi:10.3762/bjoc.14.22

• -alkynoates with N-bromosuccinimide (NBS) at rt [34], where those reactions proceed via radical spiro-cyclization and then radical 1,2-carboxyl group migration, were reported. On the other hand, diaryliodonium salts are very useful for the C-arylation of active CH groups, the O-arylation of OH groups, and the

• 3Aa or 3Aa’, the halocyclization of 2Aa with N-bromosuccinimide (NBS, 2.0 equiv)/BF3·Et2O (1.1 equiv), with 1,3-diiodo-5,5-dimethylhydantoin (DIH, 2.0 equiv)/BF3·Et2O (1.1 equiv), and with 1,3-dibromo-5,5-dimethylhydantoin (DBH, 2.0 equiv)/BF3·Et2O (1.1 equiv) was carried out to form 3-bromo-4

Aminosugar-based immunomodulator lipid A: synthetic approaches

• Alla Zamyatina

Beilstein J. Org. Chem. 2018, 14, 25–53, doi:10.3762/bjoc.14.3