Advancements in hydrochlorination of alkenes

• Daniel S. Müller

Beilstein J. Org. Chem. 2024, 20, 787–814, doi:10.3762/bjoc.20.72

• only 10–25% of the primary chloride for the reaction of tert-butylethylene with HCl in the presence of benzoyl peroxide [33]. c) Several metal halides such as AlCl3, SnCl4, FeCl3, and CuCl exhibit catalytic activities for the hydrochlorination of alkenes. The enthalpy of formation for the hydrogen

• chloride metal halide complexes are −6 kJ mol−1 for SnCl4, −8 kJ mol−1 for BiCl3, −9 kJ mol−1 for ZnCl2, −15 kJ mol−1 for CdCl2, −16 kJ mol−1 for FeCl3, and −41 kJ mol−1 for AlCl3. d) Addition of chloride-containing salts (e.g., LiCl) accelerate the reaction. e) Traces of water can increase the rate of the

• of HCl. No reaction was observed for terminal and 1,2-disubstituted alkenes such as cyclooctene (25) and 1-decene (53). Boudjouk and co-workers examined PCl3, SnCl4, SOCl2, SiCl4, Me2SiCl2, and Me3SiCl as hydrogen chloride sources [55]. They found that PCl3 and SnCl4 gave the desired

N-Sulfenylsuccinimide/phthalimide: an alternative sulfenylating reagent in organic transformations

• Fatemeh Doraghi,
• Seyedeh Pegah Aledavoud,
• Mehdi Ghanbarlou,
• Bagher Larijani and
• Mohammad Mahdavi

Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106

• imidated product 32. In 2018, an Fe-catalyzed carbosulfenylation and carboselenylation 33 of alkenes with N-(thio/seleno)phthalimides 14 was introduced by Lv and Li (Scheme 17) [54]. The use of Lewis acids, such as AlCl3, ZnCl2, InCl3, Fe(OTf)2 and Fe(acac)3 was not beneficial. However, BF3·OEt2, SnCl4

Synthetic strategies toward 1,3-oxathiolane nucleoside analogues

• Umesh P. Aher,
• Dhananjai Srivastava,
• Girij P. Singh and
• Jayashree B. S

Beilstein J. Org. Chem. 2021, 17, 2680–2715, doi:10.3762/bjoc.17.182

• reducing agent sodium borohydride. The plausible reaction mechanism was also described for this selective N-glycosylation methodology (Scheme 40). A previously reported [72] plausible mechanism involving the use of SnCl4 was considered while proposing the mechanism when using ZrCl4 catalyst for the

• phosphonate analogue 100 (Scheme 44). To obtain both the α- and β-anomers for biological assessment, TiCl4 was used as a Lewis acid in the glycosylation procedure in place of SnCl4

Synthesis of new substituted 7,12-dihydro-6,12-methanodibenzo[c,f]azocine-5-carboxylic acids containing a tetracyclic tetrahydroisoquinoline core structure

• Agnieszka Grajewska,
• Maria Chrzanowska and
• Wiktoria Adamska

Beilstein J. Org. Chem. 2021, 17, 2511–2519, doi:10.3762/bjoc.17.168

• amino acid 6a was subjected to cyclization under different acidic conditions (not shown). The reaction of 6a with TiCl4 or SnCl4 in DCM at 0 °C led exclusively to the formation of 7a (TLC analysis) but it was impossible to isolate the product in a pure form probably due to the formation of the salts

Progress and challenges in the synthesis of sequence controlled polysaccharides

• Giulio Fittolani,
• Theodore Tyrikos-Ergas,
• Denisa Vargová,
• Manishkumar A. Chaube and
• Martina Delbianco

Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129

Application of the Meerwein reaction of 1,4-benzoquinone to a metal-free synthesis of benzofuropyridine analogues

• Rashmi Singh,
• Tomas Horsten,
• Rashmi Prakash,
• Swapan Dey and
• Wim Dehaen

Beilstein J. Org. Chem. 2021, 17, 977–982, doi:10.3762/bjoc.17.79

• the Duff formylation procedure, only traces of aldehyde 16 were detected. Rieche formylation with either SnCl4 or TiCl4 resulted in a low conversion of the starting material and only traces of 16 due to the limited solubility of 13 in DCM, DCE, or chloroform. Furthermore, 16 was isolated after a

Prins cyclization-mediated stereoselective synthesis of tetrahydropyrans and dihydropyrans: an inspection of twenty years

• Asha Budakoti,
• Pradip Kumar Mondal,
• Prachi Verma and
• Jagadish Khamrai

Beilstein J. Org. Chem. 2021, 17, 932–963, doi:10.3762/bjoc.17.77

• -trisubstituted tetrahydropyran 97 through Prins cyclization, as shown in Scheme 21. Similarly, an SnCl4-catalyzed Prins reaction was reported for the synthesis of 4-chlorotetrahydropyran 100. This intermediate was further utilized for the synthesis of the natural product centrolobine, as shown in Scheme 22 [56

CF₃-substituted carbocations: underexploited intermediates with great potential in modern synthetic chemistry

• Anthony J. Fernandes,
• Armen Panossian,
• Bastien Michelet,
• Agnès Martin-Mingot,
• Frédéric R. Leroux and
• Sébastien Thibaudeau

Beilstein J. Org. Chem. 2021, 17, 343–378, doi:10.3762/bjoc.17.32

• activation (e.g., SnCl4 or ZnCl2), opening an avenue for this cation to react with various nucleophiles (Scheme 51). Such a cation can also be trapped intramolecularly by a phenyl moiety; however, the length of the appended alkyl chain appeared to be of the utmost importance in this transformation. Analogous

The biomimetic synthesis of balsaminone A and ellagic acid via oxidative dimerization

• Sharna-kay Daley and
• Nadale Downer-Riley

Beilstein J. Org. Chem. 2020, 16, 2026–2031, doi:10.3762/bjoc.16.169

• ), was subjected to the oxidants activated carbon (Act-C), potassium ferricyanide (K3[Fe(CN)6]), p-benzoquinone and stannic chloride (SnCl4). As shown in Scheme 4, with the exception of SnCl4, all oxidants resulted in the re-oxidation of the hydroxylated substrate to naphthoquinone 7. SnCl4, however

• to be explored. The oxidants cerium(IV) ammonium nitrate (CAN), ferric chloride hexahydrate (FeCl3·6H2O), vanadium pentoxide (V2O5), PIFA, and PIDA, in addition to SnCl4, were considered. Also investigated were 2-iodoxybenzoic acid (IBX) because of its implication in single-electron oxidation [24

Extension of the 5-alkynyluridine side chain via C–C-bond formation in modified organometallic nucleosides using the Nicholas reaction

• Renata Kaczmarek,
• Dariusz Korczyński,
• James R. Green and
• Roman Dembinski

Beilstein J. Org. Chem. 2020, 16, 1–8, doi:10.3762/bjoc.16.1

• of nucleoside complex 5 (20.6 mg, 28.4 μmol) and allyltrimethylsilane (100 μL, 0.629 mmol) at 0 °C was added SnCl4 (90 μL, 1.0 M, 0.090 mmol). The solution was stirred for 1 h at 0 °C, followed by 2 h at rt. Then, NH4Cl (saturated aq, 5 drops) and NaHCO3 (saturated aq, 5 drops) were added, and a

SnCl₄-catalyzed solvent-free acetolysis of 2,7-anhydrosialic acid derivatives

• Kesatebrhan Haile Asressu and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2019, 15, 2990–2999, doi:10.3762/bjoc.15.295

• thiosialoside and halide donors. Keywords: acetolysis; acetolysis products; 2,7-anhydrosialic acid; SnCl4; Introduction Sialic acids are the most prevalent monosaccharides that are found at the nonreducing ends of glycans, and they are involved in many biologically important ligand–receptor interactions [1

• the hydroxymethyl group in 10 to furnish 11 in 82% yield. After having obtained the 2,7-anhydrosialic acid derivatives 5–11, they were subjected to various Lewis acid-catalyzed ring-opening reactions. In line with this, Sc(OTf)3-, copper(II) triflate-, and SnCl4-catalyzed acetolysis of diacetylamino

• compound 12. Due to the absence of a hydrogen bond, azido-protected glycal 13 could be used as acceptor for reactions at its OH-4 and OH-8 group [36][37]. Moreover, it was used as sialyl donor in α-selective glycosylation reactions [35]. Next, acetolysis of 2,7-anhydro derivative 6 was examined with SnCl4

Regioselectivity of glycosylation reactions of galactose acceptors: an experimental and theoretical study

• Enrique A. Del Vigo,
• Carlos A. Stortz and
• Carla Marino

Beilstein J. Org. Chem. 2019, 15, 2982–2989, doi:10.3762/bjoc.15.294

• by BF3·OEt2-promoted glycosylation [18] with a short reaction time, exploiting anchimeric assistance, followed by Zemplén de-O-acylation. On the other hand, for the synthesis of the α-anomer 8, a SnCl4-promoted glycosylation was found to be very effective [19], but with a longer reaction time in

• acceptors and donors. Model Galp 3,4-diol acceptors and data obtained with B3LYP. Synthesis of glycosyl acceptors 1α/β and 2α/β. a) BzCl, pyridine, 0 °C, 2 h; b) BF3·OEt2, MeOH, CH2Cl2, 4 h; c) SnCl4, MeOH, CH2Cl2, 20 h; d) NaOMe/MeOH, CH2Cl2, 0 ºC, 2 h; e) (CH3)2C(OCH3)2, p-TsOH, acetone, rt, 16 h; f) 50

Acid-catalyzed rearrangements in arenes: interconversions in the quaterphenyl series

• Sarah L. Skraba-Joiner,
• Carter J. Holt and
• Richard P. Johnson

Beilstein J. Org. Chem. 2019, 15, 2655–2663, doi:10.3762/bjoc.15.258

• rearrangements had been described previously. Isomerization of o,o’-quaterphenyl (17) with SnCl4/AlCl3 catalysis has been reported to yield a mixture of p,p’- (12), m,p’- (13), and m,m’-quaterphenyl (14) [34]. p,p’-Quaterphenyl (12) and m,m’-quaterphenyl (14) were available commercially. To complete the series

Friedel–Crafts approach to the one-pot synthesis of methoxy-substituted thioxanthylium salts

• Kenta Tanaka,
• Yuta Tanaka,
• Mami Kishimoto,
• Yujiro Hoshino and
• Kiyoshi Honda

Beilstein J. Org. Chem. 2019, 15, 2105–2112, doi:10.3762/bjoc.15.208

• presence of a Lewis acid such as SnCl4 and AlCl3 [12][13][14]. While these reactions were proven to be useful, they require the use of stoichiometric amounts of metals and/or toxic metal reagents. Moreover, there are only a few methods for the synthesis of thioxanthylium salts despite their useful active

A review of the total syntheses of triptolide

• Xiang Zhang,
• Zaozao Xiao and
• Hongtao Xu

Beilstein J. Org. Chem. 2019, 15, 1984–1995, doi:10.3762/bjoc.15.194

• key cyclization precursor ketoester 15, which was cyclized in the presence of SnCl4 to give tricyclic intermediate 83, followed by steps of functional group modification to install the butenolide (D-ring), and to finish the racemic synthesis of the key intermediate triptophenolide methyl ether (8) in

Synthesis of polydicyclopentadiene using the Cp₂TiCl₂/Et₂AlCl catalytic system and thin-layer oxidation of the polymer in air

• Zhargolma B. Bazarova,
• Ludmila S. Soroka,
• Alex A. Lyapkov,
• Мekhman S. Yusubov and
• Francis Verpoort

Beilstein J. Org. Chem. 2019, 15, 733–745, doi:10.3762/bjoc.15.69

• cationic polymerization, are characterized by certain disadvantages. They have a low molecular weight, a fairly rigid structure of the polymer chains due to crosslinking processes occurring during polymerization. In addition, DCPD polymers obtained from "hard" catalytic systems, such as TiCl4, SnCl4, etc

Low-budget 3D-printed equipment for continuous flow reactions

• Jochen M. Neumaier,
• Amiera Madani,
• Thomas Klein and
• Thomas Ziegler

Beilstein J. Org. Chem. 2019, 15, 558–566, doi:10.3762/bjoc.15.50

• pentaacetyl glucose (1) with trimethylsilyl azide in the presence of SnCl4 directly into azide 8 (Scheme 5) as was previously described for the classical batch preparation [39]. At a resident time of 7 minutes an 80% yield of azide 8 could be achieved. Conclusion In conclusion, we have demonstrated that low

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

• -iodoxybenzoic acid) and DMP (Dess–Martin periodinane) (Table 1, entries 7 and 8) gave similar yields to the background reaction. Lastly, a Lewis acid screen (Table 1, entries 9–12) was performed. Among the tested Lewis acids, AlCl3, SnCl4, TiCl4, TMSOTf and BF3·Et2O, the latter was found to be the best choice

AuBr₃-catalyzed azidation of per-O-acetylated and per-O-benzoylated sugars

• Jayashree Rajput,
• Srinivas Hotha and
• Madhuri Vangala

Beilstein J. Org. Chem. 2018, 14, 682–687, doi:10.3762/bjoc.14.56

• ][44][45]. More commonly, glycosyl azides are synthesized from per-O-acetylated sugars using trimethylsilyl azide in the presence of a variety of Lewis acids such as SnCl4 [46], TiCl4 [47][48], BF3·OEt2 [49], TMSOTf [50][51], etc. However, at higher concentration Lewis acids can potentially lead to

Synthetic and semi-synthetic approaches to unprotected N-glycan oxazolines

• Antony J. Fairbanks

Beilstein J. Org. Chem. 2018, 14, 416–429, doi:10.3762/bjoc.14.30

• enzymes has therefore become an area of significant interest over the past 15 years [35][36]. The synthesis of N-glycan oxazolines Formation of glycosyl oxazolines Glycosyl oxazolines of monosaccharides can be produced straightforwardly using strong Lewis acids (e.g., FeCl3, SnCl4, or TMSOTf) and a fully

Fluorescent nucleobase analogues for base–base FRET in nucleic acids: synthesis, photophysics and applications

• Mattias Bood,
• Sangamesh Sarangamath,
• Moa S. Wranne,
• Morten Grøtli and
• L. Marcus Wilhelmsson

Beilstein J. Org. Chem. 2018, 14, 114–129, doi:10.3762/bjoc.14.7

• , where R = H, 7-MeO or 8-MeO [47]. a) H2NNH2 followed by H2O2, 20 h, 100 °C, 60–98%; b) PEt3, H2O, diglyme, then Na2CO3 and 5-bromouracil, rt to 120 °C, 2 h, 24–86%; c) HCl, butanol, 120 °C, 24–72 h, 27–86%; d) BSA (bis(trimethylsilyl)acetamide), Hoeffer´s α-chloro sugar, SnCl4, 0 °C to rt, 2 h, 12–41

The chemistry and biology of mycolactones

• Matthias Gehringer and
• Karl-Heinz Altmann

Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159

Synthesis of 1-indanones with a broad range of biological activity

• Marika Turek,
• Dorota Szczęsna,
• Marek Koprowski and
• Piotr Bałczewski

Beilstein J. Org. Chem. 2017, 13, 451–494, doi:10.3762/bjoc.13.48

• derivative 265 having the steroid framework from 1,2-dihydro-7-methoxy-4-vinylnaphthalene (262) and α-bromo substituted cyclopentenone 263 by the SnCl4-catalyzed Diels–Alder cycloaddition [102]. In this reaction, 1-indanone 265 was obtained in 59% yield via dehydrogenation of a mixture of cycloadducts 264a–c

Diels–Alder reactions in confined spaces: the influence of catalyst structure and the nature of active sites for the retro-Diels–Alder reaction

• Ángel Cantín,
• M. Victoria Gomez and
• Antonio de la Hoz

Beilstein J. Org. Chem. 2016, 12, 2181–2188, doi:10.3762/bjoc.12.208

• )] were prepared according to [31][32][33], using tetraethylammonium hydroxide as template, tetraethyl orthosilicate (TEOS) as silica source and Ti(IV) ethoxide, SnCl4·5H2O and metal Al as sources of heteroatoms. SSZ-53 and SSZ-59 were synthesized according to the procedures described in the literature

Rearrangements of organic peroxides and related processes

• Ivan A. Yaremenko,
• Vera A. Vil’,
• Dmitry V. Demchuk and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162

• functionalized cyclohexenones 78 lead to dihydrooxepine structures 79. Here, the combination of SnCl4 and bis(trimethylsilyl)peroxide (BTSP), in the presence of trans-1,2-diaminocyclohexane as the ligand, generated the desired products 79 in high yields (Scheme 25) [255]. The Co4HP2Mo15V3O62-catalyzed oxidation