Preparation, structure, and reactivity of bicyclic benziodazole: a new hypervalent iodine heterocycle

• Akira Yoshimura,
• Michael T. Shea,
• Cody L. Makitalo,
• Melissa E. Jarvi,
• Gregory T. Rohde,
• Akio Saito,
• Mekhman S. Yusubov and
• Viktor V. Zhdankin

Beilstein J. Org. Chem. 2018, 14, 1016–1020, doi:10.3762/bjoc.14.87

• -iodoisophthalic acid (2). Firstly, 2-iodoisophthalic acid (2) was converted to the corresponding acyl chloride 8 by treatment with thionyl chloride (Scheme 2). In the second step, acyl chloride 8 reacted with appropriate alkylamines to give the corresponding 2-iodo-N,N’-dialkylisophthalamides 6 in good yields

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

• pyridine to give 1,3,6-trisubstitutedpyrazolo[3,4-b]pyrazine-5-carbonitriles 230 in good yields. 5-Carbonitrilepyrazolo[3,4-b]pyrazines 230 were hydrolyzed to corresponding pyrazolo[3,4-b]pyrazine-5-carboxylic acids 231 and subsequently converted to acid chloride 232 at reflux temperature with thionyl

• chloride (SOCl2) which underwent intramolecular Friedel–Crafts reaction in presence of Lewis acid to give 3-methyl-1-phenyl-1H-indeno[2,1-e]pyrazolo[3,4-b]pyrazin-5-one (233). Compound 233 was used to synthesize several other indenopyrazolopyrazinone derivatives by reaction with active methylene compounds

Photocatalytic formation of carbon–sulfur bonds

• Alexander Wimmer and
• Burkhard König

Beilstein J. Org. Chem. 2018, 14, 54–83, doi:10.3762/bjoc.14.4

• disulfide, thioamide derivatives and sulfides Disulfides and thiosulfates Sulfoxides Sulfinic acids, sulfinate salts and sulfinamides Sulfonyl halides, sulfonyl hydrazines, thionyl chloride and sulfur dioxide C–S bond formations initiated by irradiation with light of wavelengths shorter than 380 nm or by

Hydrolysis, polarity, and conformational impact of C-terminal partially fluorinated ethyl esters in peptide models

• Vladimir Kubyshkin and
• Nediljko Budisa

Beilstein J. Org. Chem. 2017, 13, 2442–2457, doi:10.3762/bjoc.13.241

• was cooled down in an ice bath. Thionyl chloride (0.1 mL, 1.38 mmol, 2.2 equiv) was added, followed by 2-fluoroethanol (80 μl, 1.38 mmol, 2.2 equiv). The mixture was stirred at ambient temperature for 14 hours. The solvent was removed under reduced pressure, and the resulting crude material was

• subjected to a silica gel (20 g) column purification using an ethyl acetate/methanol 39:1 eluent. 55 mg of 3 was obtained as a clear oil (yield 42%), Rf = 0.63 (ethyl acetate/methanol 39:1). Compound 5 was obtained in an analogous procedure to 3 starting from N-acetylproline (100 mg, 0.64 mmol), thionyl

• chloride (0.1 mL, 1.4 mmol, 2.2 equiv) and trifluoroethanol (0.12 mL, 1.6 mmol, 2.5 equiv). 141 mg of the product was obtained as a clear oil (yield 93%), Rf = 0.73 (ethyl acetate/methanol 39:1). Esterification with diazoalkanes No special precautions were applied when working with 2,2-difluorodiazoethane

Intramolecular glycosylation

• Xiao G. Jia and
• Alexei V. Demchenko

Beilstein J. Org. Chem. 2017, 13, 2028–2048, doi:10.3762/bjoc.13.201

• application, glycosyl donor precursors were reacted with phthalic anhydride to afford the corresponding esters. The activation with thionyl chloride was used for tethering the donors to the glycosyl acceptor counterpart and the regioselectivity was controlled using tin-mediated coupling under microwave

A novel approach to oxoisoaporphine alkaloids via regioselective metalation of alkoxy isoquinolines

• Benedikt C. Melzer and
• Franz Bracher

Beilstein J. Org. Chem. 2017, 13, 1564–1571, doi:10.3762/bjoc.13.156

• to increase the yield. As described above, attempted direct intramolecular Friedel–Crafts-type cyclization of 10c catalyzed by trifluoromethanesulfonic acid [25] failed completely. Also, generation of an acid chloride from 11c with thionyl chloride, followed by the reaction with AlCl3 did not even

BODIPY-based fluorescent liposomes with sesquiterpene lactone trilobolide

• Ludmila Škorpilová,
• Silvie Rimpelová,
• Michal Jurášek,
• Miloš Buděšínský,
• Jana Lokajová,
• Roman Effenberg,
• Petr Slepička,
• Tomáš Ruml,
• Eva Kmoníčková,
• Pavel B. Drašar and
• Zdeněk Wimmer

Beilstein J. Org. Chem. 2017, 13, 1316–1324, doi:10.3762/bjoc.13.128

• reaction of 4-iodo-L-phenylalanine with thionyl chloride in MeOH in quantitative yield [33]. The successive acylation of the α-amino group with 5-azidovaleric acid catalyzed by T3P (propylphosphonic anhydride) in the mixture of pyridine and AcOEt gave azidoterminated product 1 in 70% yield. Alkaline

Molecular-level architectural design using benzothiadiazole-based polymers for photovoltaic applications

• Vinila N. Viswanathan,
• Arun D. Rao,
• Upendra K. Pandey,
• Arul Varman Kesavan and
• Praveen C. Ramamurthy

Beilstein J. Org. Chem. 2017, 13, 863–873, doi:10.3762/bjoc.13.87

• synthesis of monomer M1 started with the cyclization of o-phenylenediamine with thionyl chloride in the presence of triethylamine, a strong base and dichloromethane as the solvent at 0 °C. Compound 1 was then treated with bromine and HBr to obtain 4,7-dibromobenzo[c][1,2,5]thiadiazole (2). The latter

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

• benzoic acids 15 with thionyl chloride, reacted with ethylene and the resulting intermediates underwent an intramolecular Friedel–Crafts alkylation to form 1-indanones 16 (Scheme 6). Both arylpropionic and 3-arylacrylic acids 17 underwent cyclization in the presence of polyphosphoric and sulfuric acids to

• chloride with thionyl chloride, led to the formation of 1-indanone 32 which was further transformed into the desired inhibitors 33 (Scheme 12). In the synthesis of 5-hydroxy-1-indanone, Chen and Li reacted 3-chloropropionyl chloride with 2,6-dibromophenol to give 2,6-dibromophenyl 3-chloropropionate [29

Diastereoselective anodic hetero- and homo-coupling of menthol-, 8-methylmenthol- and 8-phenylmenthol-2-alkylmalonates

• Matthias C. Letzel,
• Hans J. Schäfer and
• Roland Fröhlich

Beilstein J. Org. Chem. 2017, 13, 33–42, doi:10.3762/bjoc.13.5

• with benzyl chloroformate (Scheme 2b). The benzyl malonates 5 and 6 are converted to the corresponding benzyl malonyl chlorides with thionyl chloride. To these at −40 °C the auxiliary menthol (1), 8-p-anisylmenthol (4) [19], 8-methylmenthol (2) [20] or 8-phenylmenthol (3) [21] was added in the presence

• chloride (1.3 g, 10.8 mmol) were added and the mixture was refluxed for 3 h. After evaporation of the solvent and the unreacted thionyl chloride in vacuum, the remaining yellow oil was dissolved in 20 mL methylene chloride without further purification and cooled to −40 °C. Under an argon atmosphere 2.81

• solution in the range of 5–10 °C with a coolant of −25 °C. The further work-up follows the procedure given for the hetero-coupling reaction. General procedure for the preparation of the menthol esters: To a solution of 4.3 mmol of monobenzyl malonate 5 or 6 in 20 mL dry methylene chloride 0.8 mL thionyl

Elongated and substituted triazine-based tricarboxylic acid linkers for MOFs

• Arne Klinkebiel,
• Ole Beyer,
• Barbara Malawko and
• Ulrich Lüning

Beilstein J. Org. Chem. 2016, 12, 2267–2273, doi:10.3762/bjoc.12.219

• unsymmetric trimerization of the desired tribromotriazines 3. The synthesis of 4-bromo-3-nitrobenzoyl chloride (5b) was straightforward. Commercially available 4-bromobenzoic acid (8) was nitrated according to a known procedure [18]. The reaction with thionyl chloride provided then acid chloride 5b (Figure 5

• performed with the free carboxylic acid 11 [20] or with ester 12 [21][22]. In order to generate the methoxy-substituted benzoyl chloride 5c, methoxy ester 13 was cleaved first [23] and the resulting acid 14 was reacted with thionyl chloride. All steps were known from the literature and have been carried out

Synthesis of highly functionalized 2,2'-bipyridines by cyclocondensation of β-ketoenamides – scope and limitations

• Paul Hommes and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2016, 12, 1170–1177, doi:10.3762/bjoc.12.112

• derivative 2-PyCOBt [25][26]. During an attempt to prepare β-ketoenamide 3a by in situ generation of picolinic acid chloride with thionyl chloride under heating and by amide formation of the resulting product with 2a we isolated not only the expected compound 3a but as major component the meta-chlorinated

• (see Supporting Information File 1). The in situ generation of the acid chloride with thionyl chloride was possible without the undesired chlorination with the more electron-deficient 6-methoxycarbonyl-substituted 2-pyridine carboxylic acid delivering with 2a the desired β-ketoenamide 3g with excellent

Chiral cyclopentadienylruthenium sulfoxide catalysts for asymmetric redox bicycloisomerization

• Barry M. Trost,
• Michael C. Ryan and
• Meera Rao

Beilstein J. Org. Chem. 2016, 12, 1136–1152, doi:10.3762/bjoc.12.110

• sulfinamides [48]. The application of this method to the synthesis of our chiral sulfoxide tethers is presented in Scheme 4. Tosyl protection of the primary amine of (+)-norephedrine and treatment with thionyl chloride furnishes chiral oxathiazolidine 2-oxide 7 as a single diastereomer in 87% yield over two

Synthesis of a deuterated probe for the confocal Raman microscopy imaging of squalenoyl nanomedicines

• Eric Buchy,
• Branko Vukosavljevic,
• Maike Windbergs,
• Dunja Sobot,
• Camille Dejean,
• Simona Mura,
• Patrick Couvreur and
• Didier Desmaële

Beilstein J. Org. Chem. 2016, 12, 1127–1135, doi:10.3762/bjoc.12.109

• (along with N2 and the trisyl anion) which upon condensation with squalenaldehyde 10 furnished the desired allylic alcohol 16 in 59% yield. Reduction of the hydroxy group of 16 was straightforwardly achieved in 47% yield by treatment with a large excess of thionyl chloride followed by LiAlD4 reduction

• . We next turned to the elaboration of the isopropylidene-d6 moiety. In the event, the Shapiro reaction using trisylhydrazide 14 delivered the expected allylic alcohol 21 in 70% yield. The latter afforded the deuterated ketal 22 in 52% yield, upon sequential treatment with thionyl chloride and LiAlD4

• using the van Tamelen sequence (i. 1 equiv NBS, THF, H2O; ii. K2CO3, MeOH; iii. H3IO6, Et2O) afforded the aldehyde 26 in 16% overall yield. Uneventfully, the Shapiro reaction with trisylhydrazone 14 produced the allylic alcohol 27. Thionyl chloride treatment followed by LiAlD4 reduction delivered

A cross-metathesis approach to novel pantothenamide derivatives

• Jinming Guan,
• Matthew Hachey,
• Lekha Puri,
• Vanessa Howieson,
• Kevin J. Saliba and
• Karine Auclair

Beilstein J. Org. Chem. 2016, 12, 963–968, doi:10.3762/bjoc.12.95

• reflux conditions (100 °C) with ethanol and thionyl chloride added in two portions separated by three hours [18]. Alternatively, it was found here that a microwave reactor reduced the overall reaction time down to 30 minutes, with an isolated yield of 90%, comparable to that of the thermal reaction

Profluorescent substrates for the screening of olefin metathesis catalysts

• Raphael Reuter and
• Thomas R. Ward

Beilstein J. Org. Chem. 2015, 11, 1886–1892, doi:10.3762/bjoc.11.203

• platereader was used. N-Allyl-5-methoxynaphthalene-1-sulfonamide (12). To a DMF solution (30 mL) of sodium 5-methoxynaphthalene-1-sulfonate (11, 1.30 g, 5.00 mmol, 1.00 equiv), cooled on an ice bath, thionyl chloride (1.09 mL, 15.0 mmol, 3.00 equiv) was added dropwise. After the complete addition, the ice

The preparation of new functionalized [2.2]paracyclophane derivatives with N-containing functional groups

• Henning Hopf,
• Swaminathan Vijay Narayanan and
• Peter G. Jones

Beilstein J. Org. Chem. 2015, 11, 437–445, doi:10.3762/bjoc.11.50

• pseudo-para-substituted [2.2]paracyclophane derivatives carrying N-functional groups. As shown in Scheme 4, the crucial substrate 25 was prepared from the pseudo-para-dibromide 24 [24][29]. Treating 25 with thionyl chloride in DMF yielded the bis(acyl chloride) 26 in quantitative yield. In contrast to

Versatile synthesis of amino acid functionalized nucleosides via a domino carboxamidation reaction

• Vicky Gheerardijn,
• Jos Van den Begin and
• Annemieke Madder

Beilstein J. Org. Chem. 2014, 10, 2566–2572, doi:10.3762/bjoc.10.268

• available, we have synthesized histidine as a methyl ester (2) with thionyl chloride in methanol in good yield according to literature procedures [49]. Although basic hydrolysis of alkyl esters has been shown to imply long reaction times, side-product formation and low reaction yields [50], we found that

Synthesis and biological evaluation of novel N-α-haloacylated homoserine lactones as quorum sensing modulators

• Michail Syrpas,
• Ewout Ruysbergh,
• Christian V. Stevens,
• Norbert De Kimpe and
• Sven Mangelinckx

Beilstein J. Org. Chem. 2014, 10, 2539–2549, doi:10.3762/bjoc.10.265

• thionyl chloride [27]. These reaction conditions allowed the synthesis of α-brominated fatty acids 5 in a highly selective and efficient manner. Brominated AHL analogues 6a–f (dr 1:1) were prepared in acceptable yields by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)-mediated coupling of the

• ). Synthesis of α-brominated fatty acids 5b–f To a flask equipped with a sodium hydroxide trap the corresponding fatty acid 4 (0.065 mol) and thionyl chloride (5 equiv, 40 mL, 0.325 mol) were added. The reaction mixture was stirred at 50 °C in a water bath. Then, liquid bromine (3 equiv, 5 mL, 0.195 mol) was

• added dropwise and the reaction mixture was stirred under reflux for 6 h and then at room temperature overnight. The excess of thionyl chloride was then removed by distillation. To a beaker containing distilled water in an ice bath, the dark red residue was slowly added and manually stirred. Afterwards

Visible light photoredox-catalyzed deoxygenation of alcohols

• Daniel Rackl,
• Viktor Kais,
• Peter Kreitmeier and
• Oliver Reiser

Beilstein J. Org. Chem. 2014, 10, 2157–2165, doi:10.3762/bjoc.10.223

• produced by thermal dehydration of acetic acid [12], the overall sequence to the benzoylated starting material 6e does not require any type of activation reagents such as thionyl chloride or DCC that are often used for ester formation, but ultimately only requires energy in form of heat. After the

A scalable synthesis of the (S)-4-(tert-butyl)-2-(pyridin-2-yl)-4,5-dihydrooxazole ((S)-t-BuPyOx) ligand

• Hideki Shimizu,
• Jeffrey C. Holder and
• Brian M. Stoltz

Beilstein J. Org. Chem. 2013, 9, 1637–1642, doi:10.3762/bjoc.9.187

• intermediate, alcohol 4 was reacted with thionyl chloride (Table 2, entries 4–10) to yield chloride 11, which was isolated as the hydrochloric acid salt and dried under vacuum. This compound proved to be bench stable and was spectroscopically unchanged after being left open to oxygen atmosphere and

Enantioselective reduction of ketoimines promoted by easily available (S)-proline derivatives

• Martina Bonsignore,
• Maurizio Benaglia,
• Laura Raimondi,
• Manuel Orlandi and
• Giuseppe Celentano

Beilstein J. Org. Chem. 2013, 9, 633–640, doi:10.3762/bjoc.9.71

• thionyl chloride under reflux for 4 hours. The catalytic efficiency of these catalysts was evaluated in the stereoselective reduction of the N-phenyl imine of acetophenone (Table 2). After running the reaction in dichloromethane at 0 °C for 18 hours, all the catalysts afforded the desired product in

Asymmetric synthesis of host-directed inhibitors of myxoviruses

• Terry W. Moore,
• Kasinath Sana,
• Dan Yan,
• Pahk Thepchatri,
• John M. Ndungu,
• Manohar T. Saindane,
• Mark A. Lockwood,
• Michael G. Natchus,
• Dennis C. Liotta,
• Richard K. Plemper,
• James P. Snyder and
• Aiming Sun

Beilstein J. Org. Chem. 2013, 9, 197–203, doi:10.3762/bjoc.9.23

• excess (>98% ee), we utilized the Mitsunobu reaction of 2-mercaptobenzimidazoles with an amide obtained from (L)-lactic acid (17). Using one equivalent each of 2-mercaptobenzimidazole and α-hydroxyamide 13 (prepared from thionyl chloride-mediated coupling of (L)-lactic acid (17) and 2-chloro-4

• approaches. Preparation of chiral propionamides by HATU-mediated coupling (a) or thionyl chloride-mediated coupling (b). In vitro screening of analogues of 1. Antiviral potencies and solubilities for 1 and analogues. Supporting Information Contains detailed synthetic procedures and characterization data for

Synthesis of 5-(ethylsulfonyl)-2-methoxyaniline: An important pharmacological fragment of VEGFR2 and other inhibitors

• Miroslav Murár,
• Gabriela Addová and
• Andrej Boháč

Beilstein J. Org. Chem. 2013, 9, 173–179, doi:10.3762/bjoc.9.20

• sodium salt C was subsequently converted to the hydrochloride salt of 3-amino-4-hydroxybenzene-1-sulfonyl chloride (D) by treatment with thionyl chloride at room temperature. The amino group of D was protected in the form of a 2-methylbenzo[d]oxazole-5-sulfonyl chloride (E) by reaction of D with (EtO)3CH

The diketopiperazine-fused tetrahydro-β-carboline scaffold as a model peptidomimetic with an unusual α-turn secondary structure

• Francesco Airaghi,
• Andrea Fiorati,
• Giordano Lesma,
• Manuele Musolino,
• Alessandro Sacchetti and
• Alessandra Silvani

Beilstein J. Org. Chem. 2013, 9, 147–154, doi:10.3762/bjoc.9.17

• troublesome under a wide range of conditions, probably due to the severe steric hindrance of both the amine and acid coupling partners. At the end, acceptable yields could be obtained via formation of the chloride intermediate [48], by reaction of acid 4 with thionyl chloride, and subsequent coupling with 2