Three-component N-alkenylation of azoles with alkynes and iodine(III) electrophile: synthesis of multisubstituted N-vinylazoles

• Jun Kikuchi,
• Roi Nakajima and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2024, 20, 891–897, doi:10.3762/bjoc.20.79

• to 66% and 55%, respectively (Table 1, entries 6 and 7). The addition of a base such as K2CO3 completely shut down the desired reaction (Table 1, entry 8). It is worth noting that the replacement of 1 with N-iodosuccinimide, a common iodine(I) electrophile, failed to promote an analogous

Consecutive four-component synthesis of trisubstituted 3-iodoindoles by an alkynylation–cyclization–iodination–alkylation sequence

• Nadia Ledermann,
• Alae-Eddine Moubsit and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2023, 19, 1379–1385, doi:10.3762/bjoc.19.99

• generated by a consecutive four-component reaction starting from ortho-haloanilines, terminal alkynes, N-iodosuccinimide, and alkyl halides in yields of 11–69%. Initiated by a copper-free alkynylation, followed by a base-catalyzed cyclizive indole formation, electrophilic iodination, and finally

• (aza)indoles. As already shown for N-alkyl 7-azaindole formation in one case, the crucial 7-azaindole anion could be trapped with electrophilic iodine (from N-iodosuccinimide), resulting in a 3-iodo-7-azaindole anion, which could then be alkylated, still in a one-pot fashion [34]. Therefore, we set out

• to directly employ these standard conditions to the sequence of ortho-haloanilines 1, terminal alkynes 2, N-iodosuccinimide (3), and alkyl halides 4 to screen the scope of the one-pot synthesis of trisubstituted 3-iodoindoles 5 in a consecutive four-component fashion (Scheme 2). The sequence

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

Mechanochemical halogenation of unsymmetrically substituted azobenzenes

• Dajana Barišić,
• Mario Pajić,
• Ivan Halasz,
• Darko Babić and
• Manda Ćurić

Beilstein J. Org. Chem. 2022, 18, 680–687, doi:10.3762/bjoc.18.69

• PdII-catalyzed iodination of L6–8 was conducted with N-iodosuccinimide (NIS) as the iodine source. The reaction time for the iodination of L6 was the same as for the analogous bromination reaction (Table 2, entry 10). Iodination of L7 and L8 was completed within five and seven hours, respectively

Ready access to 7,8-dihydroindolo[2,3-d][1]benzazepine-6(5H)-one scaffold and analogues via early-stage Fischer ring-closure reaction

• Irina Kuznetcova,
• Felix Bacher,
• Daniel Vegh,
• Hsiang-Yu Chuang and
• Vladimir B. Arion

Beilstein J. Org. Chem. 2022, 18, 143–151, doi:10.3762/bjoc.18.15

• delivered 3c in 53% yield (Scheme 6). In an alternative approach we tried to synthesize non-benzylated species 1a from methyl indol-2-ylacetate. Iodination at position 3 of the indole backbone in the presence of N-iodosuccinimide [45] followed by Ullmann cross-coupling with o-bromo-nitrobenzene [46] was

Total synthesis of the O-antigen repeating unit of Providencia stuartii O49 serotype through linear and one-pot assemblies

• Tanmoy Halder and
• Somnath Yadav

Beilstein J. Org. Chem. 2021, 17, 2915–2921, doi:10.3762/bjoc.17.199

• described in Scheme 2. With the monosaccharide building blocks in hand, the galactosamine donor 6 was coupled with galactose acceptor 7 by activation of the thioglycoside using N-iodosuccinimide (NIS) in the presence of TMSOTf to afford the desired disaccharide β-ᴅ-GalpNHTroc-(1→4)-α-ᴅ-Galp (4) in 85% yield

Beyond ribose and phosphate: Selected nucleic acid modifications for structure–function investigations and therapeutic applications

• Christopher Liczner,
• Kieran Duke,
• Gabrielle Juneau,
• Martin Egli and
• Christopher J. Wilds

Beilstein J. Org. Chem. 2021, 17, 908–931, doi:10.3762/bjoc.17.76

• work was extended to incorporate these modifications into oligonucleotides containing all four bases [202]. N-Iodosuccinimide promoted the alkoxylation of the 4'–5'-enol acetates yielded the corresponding 5'-acetoxy-5'-iodo-4'-methoxy intermediates [202]. These intermediates were hydrolyzed with a

Progress in the total synthesis of inthomycins

• Bidyut Kumar Senapati

Beilstein J. Org. Chem. 2021, 17, 58–82, doi:10.3762/bjoc.17.7

• 82% yield (83% ee). Subsequent free radical hydrostannation on (−)-98 produced (+)-99 as the major product of a 46:1 mixture of (Z/E)-α-stannylated geometric isomers. The purified vinylstannane (+)-99 underwent iodination stereoselectively with excess N-iodosuccinimide to give (−)-100, which was then

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

• hydrofluoride) in the presence of an activating agent, e.g., N-iodosuccinimide (NCS) in a usual glass flask, a mixture of products 55–57 were obtained (Scheme 12). Interestingly, when a polypropylene tube was used instead of glass flask, the expected hexafluorosumanene 55 was obtained in 73% yield. To explore

• they are the most trustworthy strategies for direct functionalization of aromatic scaffolds [50]. As can be inspected from Scheme 18, monoiodosumanene 79 was obtained by gold-catalyzed iodination in the presence of N-iodosuccinimide (NIS). The mononitrosumanene 80 was achieved through the nitration

Synthesis of the tetrasaccharide repeating unit of the O-specific polysaccharide of Azospirillum doebereinerae type strain GSF71^T using linear and one-pot iterative glycosylations

• Arin Gucchait,
• Pradip Shit and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2020, 16, 1700–1705, doi:10.3762/bjoc.16.141

• glycosylations followed by in situ removal of the PMB group in one pot. The stereochemical outcome of the newly formed glycosidic linkages was excellent using thioglycoside derivatives as glycosyl donors and a combination of N-iodosuccinimide (NIS) and perchloric acid supported on silica (HClO4-SiO2) as the

• elongation C-3 hydroxy group in the ʟ-rhamnosyl thioglycoside donor 3 allowed carrying out the stereoselective glycosylation steps followed by the removal of the PMB group [25] in one pot. This was achieved by using a combination [26][27][28][29][30] of N-iodosuccinimide (NIS) and perchloric acid supported

Convenient synthesis of the pentasaccharide repeating unit corresponding to the cell wall O-antigen of Escherichia albertii O4

• Tapasi Manna,
• Arin Gucchait and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2020, 16, 106–110, doi:10.3762/bjoc.16.12

• intermediates, it was decided to proceed through a step-economic block synthetic strategy to achieve the target pentasaccharide derivative. Accordingly, stereoselective glycosylation of a ᴅ-galactosamine derivative 2 with a ᴅ-galactose thioglycoside derivative 3 in the presence of a combination [26][27] of N

• -iodosuccinimide (NIS) and perchloric acid supported over silica (HClO4/SiO2) [28][29] furnished disaccharide derivative 8 in 79% yield, which on de-O-acetylation using sodium methoxide [30] gave the disaccharide acceptor 9 in 95% yield. NMR spectral analysis of compound 9 confirmed its formation with appropriate

Chemical synthesis of the pentasaccharide repeating unit of the O-specific polysaccharide from Escherichia coli O132 in the form of its 2-aminoethyl glycoside

• Debasish Pal and
• Balaram Mukhopadhyay

Beilstein J. Org. Chem. 2019, 15, 2563–2568, doi:10.3762/bjoc.15.249

• ). Glycosylation of the known GlcNPhth acceptor 2 [12] and the rhamnosyl donor 3 [13] through the activation of thioglycoside using N-iodosuccinimide (NIS) in the presence of TMSOTf gave the Rha-(1→3)-GlcNPhth disaccharide 4 in 84% yield. The presence of a participating acetate group at the 2-position of the

Heck- and Suzuki-coupling approaches to novel hydroquinone inhibitors of calcium ATPase

• Robert J. Kempton,
• Taylor A. Kidd-Kautz,
• Soizic Laurenceau and
• Stefan Paula

Beilstein J. Org. Chem. 2019, 15, 971–975, doi:10.3762/bjoc.15.94

• 4b from 1,4-dimethoxybenzene, among them iodine in the presence of trichlorocyanuric acid and silica gel [9], I2/periodic acid [10], I2/silfen [11], N-iodosuccinimide [12], and potassium iodide/potassium iodate [13]. In our hands the best yields of 4b were obtained using iodine in the presence of

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

• -benzylidene-β-D-glucopyranoside (11) in 70% yield. Stereoselective glycosylation of compound 11 with D-mannose-derived ethyl 2-O-acetyl-3,4,6-tri-O-benzyl-1-thio-α-D-mannopyranoside (3) [14] in the presence of a combination of N-iodosuccinimide (NIS) and trimethylsilyl trifluoromethanesulfonate (TMSOTf) [22

Sigmatropic rearrangements of cyclopropenylcarbinol derivatives. Access to diversely substituted alkylidenecyclopropanes

• Guillaume Ernouf,
• Jean-Louis Brayer,
• Christophe Meyer and
• Janine Cossy

Beilstein J. Org. Chem. 2019, 15, 333–350, doi:10.3762/bjoc.15.29

• reactions which were applied to α-hydroxy esters 74 and 75 using N-iodosuccinimide (MeCN/H2O, 50 °C) [70], or to the N-benzylamine generated from α-amino ester 71 (by reductive animation with benzaldehyde) in the presence of I2 and K2CO3 (MeCN, rt) [71]. These iodocyclizations led to the oxabicyclic

Synthesis, biophysical properties, and RNase H activity of 6’-difluoro[4.3.0]bicyclo-DNA

• Sibylle Frei,
• Adam K. Katolik and
• Christian J. Leumann

Beilstein J. Org. Chem. 2019, 15, 79–88, doi:10.3762/bjoc.15.9

• corresponding siloxydifluorocyclopropane [38][39][40]. However, based on previous observations in the nucleoside synthesis of the 6’F-bc4,3-T [37] we thought to construct the 6’-diF-bc4,3 building block in utilizing this methodology. Along this synthesis, the glycal 1 was treated with N-iodosuccinimide (NIS) in

6’-Fluoro[4.3.0]bicyclo nucleic acid: synthesis, biophysical properties and molecular dynamics simulations

• Sibylle Frei,
• Andrei Istrate and
• Christian J. Leumann

Beilstein J. Org. Chem. 2018, 14, 3088–3097, doi:10.3762/bjoc.14.288

• spectra (Supporting Information File 1). The plan for the pyrimidine nucleoside synthesis comprised the use of the meanwhile well-established β-selective N-iodosuccinimide (NIS)-mediated addition of a persilylated nucleobase to a tricyclic glycal [43][45][53][54]. Therefore, the gem-difluorinated

Cobalt bis(acetylacetonate)–tert-butyl hydroperoxide–triethylsilane: a general reagent combination for the Markovnikov-selective hydrofunctionalization of alkenes by hydrogen atom transfer

• Xiaoshen Ma and
• Seth B. Herzon

Beilstein J. Org. Chem. 2018, 14, 2259–2265, doi:10.3762/bjoc.14.201

• formation of 4d represents the first Markovnikov-selective alkene hydrobromination by an HAT pathway. Attempts to extend this reaction to hydroiodination using related reagents, p-toluenesulfonyl iodide, N-iodosuccinimide, or molecular iodine failed to provide the expected product (see Supporting

Rapid transformation of sulfinate salts into sulfonates promoted by a hypervalent iodine(III) reagent

• Elsa Deruer,
• Vincent Hamel,
• Samuel Blais and
• Sylvain Canesi

Beilstein J. Org. Chem. 2018, 14, 1203–1207, doi:10.3762/bjoc.14.101

• )-iodanes were both acceptable substrates, but the process was inefficient with (VII)-iodane species. We surmise that IBX and DMP are rapidly reduced to a (III)-iodane in the presence of an alcohol, and that this species is most likely the reagent promoting the formation of compound 4a. Iodine and N

• -iodosuccinimide (NIS) were also tested; it appeared that this process was much more efficient in the presence of iodane sources (Table 1). DIB was chosen as the hypervalent iodine reagent of choice since it is more compatible with alcohols than IBX or DMP. The reaction proceeded in modest to good yields depending

Hypervalent iodine-mediated Ritter-type amidation of terminal alkenes: The synthesis of isoxazoline and pyrazoline cores

• Sang Won Park,
• Soong-Hyun Kim,
• Jaeyoung Song,
• Ga Young Park,
• Darong Kim,
• Tae-Gyu Nam and
• Ki Bum Hong

Beilstein J. Org. Chem. 2018, 14, 1028–1033, doi:10.3762/bjoc.14.89

• [23][24][25][26][27]. Results and Discussion As depicted in Scheme 1, we have previously reported an inter-/intramolecular alkene diamination using either N-iodosuccinimide (NIS) or a phenyliodine diacetate (PIDA)/halide additive combination [28][29][30]. Vinylanilines and vinylaminopyridines in

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

• . China 10.3762/bjoc.14.31 Abstract A solvent-free palladium-catalyzed ortho-iodination of acetanilides using N-iodosuccinimide as the iodine source has been developed under ball-milling conditions. This present method avoids the use of hazardous organic solvents, high reaction temperature, and long

• -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

• products 3a and 4a were obtained in 73% and 77% yields, respectively (Scheme 4). Conclusion In summary, we have developed a solvent-free and efficient protocol to synthesize ortho-iodinated acetanilide derivatives with Pd(OAc)2 as the catalyst and N-iodosuccinimide as the halogen source under mechanical

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

• TBAB/K2S2O8 at 90 °C [31], the cyanomethyl-radical-mediated reaction of aryl 2-alkynoates with tert-butyl peroxybenzoate (TBPB)/acetonitrile at 130 °C [32], the sunlight-promoted reaction of aryl 2-alkynoates with N-iodosuccinimide (NIS) at rt [33], and the visible-light-mediated reaction of aryl 2

• (3Aa’) with N-iodosuccinimide (NIS, 2.0 equiv)/BF3·Et2O (2.0 or 1.1 equiv) was studied based on the previous reports [45][46], as shown in Table 2. However, 3-iodo-4-phenylcoumarin (3Aa’) was obtained in low to moderate yields (Table 2, entries 1 and 2). To improve the yield of 3-halo-4-phenylcoumarins

5-Aminopyrazole as precursor in design and synthesis of fused pyrazoloazines

• Ranjana Aggarwal and
• Suresh Kumar

Beilstein J. Org. Chem. 2018, 14, 203–242, doi:10.3762/bjoc.14.15

• . The reaction of 5-amino-4-cyanopyrazole (208) and formamide was carried out by Todorovic et al. [136] under microwave irradiation at 200 °C to give 4-aminopyrazolo[3,4-d]pyrimidine (223) which on iodination with N-iodosuccinimide followed by N1-alkylation (Mitsunobu or substitution) provided

Aminosugar-based immunomodulator lipid A: synthetic approaches

• Alla Zamyatina

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

Ring-size-selective construction of fluorine-containing carbocycles via intramolecular iodoarylation of 1,1-difluoro-1-alkenes

• Takeshi Fujita,
• Ryo Kinoshita,
• Tsuyoshi Takanohashi,
• Naoto Suzuki and
• Junji Ichikawa

Beilstein J. Org. Chem. 2017, 13, 2682–2689, doi:10.3762/bjoc.13.266

• -difluoroallyl)biphenyl (1a) as a model substrate. To generate a highly reactive, cationic iodine species, several iodine sources were used with acid or metal activators (Table 1, entries 1–3). Upon treatment with N-iodosuccinimide (NIS) and trimethylsilyl trifluoromethanesulfonate (TMSOTf) in a 1:1 mixed

• dichloromethane (1.5 mL) solution of N-iodosuccinimide (NIS, 27 mg, 0.12 mmol) was added trimethylsilyl trifluoromethanesulfonate (22 μL, 0.12 mmol) at 0 °C. After stirring at the same temperature for 10 min, a dichloromethane (1.0 mL) solution of 2-(3,3-difluoroallyl)biphenyl (5a, 23 mg, 0.10 mmol) was added to