Skeletal rearrangement of 6,8-dioxabicyclo[3.2.1]octan-4-ols promoted by thionyl chloride or Appel conditions

• Martyn Jevric,
• Julian Klepp,
• Johannes Puschnig,
• Oscar Lamb,
• Christopher J. Sumby and
• Ben W. Greatrex

Beilstein J. Org. Chem. 2024, 20, 823–829, doi:10.3762/bjoc.20.74

• the alkoxytriphenylphosphonium intermediate. Several reactions of the products were investigated to show the utility of the rearrangement. Keywords: bicyclic ring; cyrene; levoglucosenone; rearrangement; thionyl chloride; Introduction The 6,8-dioxabicyclo[3.2.1]octane derivative levoglucosenone (1

Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• 6-membered rings containing a sulfoxide moiety. For instance, Grainger and co-workers designed a series of naphthotrithiin-2-oxides, such as 47, to act as SO transfer reagents (Scheme 13) [79]. These triplet SO precursors were prepared by treatment of 1,8-naphthalene dithiols with thionyl chloride

A novel recyclable organocatalyst for the gram-scale enantioselective synthesis of (S)-baclofen

• Gyula Dargó,
• Dóra Erdélyi,
• Balázs Molnár,
• Péter Kisszékelyi,
• Zsófia Garádi and
• József Kupai

Beilstein J. Org. Chem. 2023, 19, 1811–1824, doi:10.3762/bjoc.19.133

• corresponding acyl chloride 11 with thionyl chloride. Finally, the cinchona squaramide with linker 7 and the octadecylated gallic acid chloride 11 were coupled to form an amide using triethylamine as a base. The crude product was purified by chromatography and precipitated from acetonitrile to gain the

Synthetic strategies for the preparation of γ-phostams: 1,2-azaphospholidine 2-oxides and 1,2-azaphospholine 2-oxides

• Jiaxi Xu

Beilstein J. Org. Chem. 2022, 18, 889–915, doi:10.3762/bjoc.18.90

• -amino-4-(hydroxy(methyl)phosphoryl)butanoic acid (68) by treatment with phosphorus pentachloride or thionyl chloride, respectively, in the presence of triethylamine when he synthesized phosphonopeptides. Similar yields were obtained for these two different chlorinating reagents. Ethyl 2-methyl-1,2

• -(diethoxyphosphoryl)benzoic acid (198) and amine derivatives. They first converted 2-(diethoxyphosphoryl)benzoic acid (198) into its anhydride 1-ethoxy-3H-benzo[c][1,2]oxaphosphol-3-one 1-oxide (199) by treatment with thionyl chloride under nitrogen. The mixed anhydride 199 was further treated with phosphorus

First series of N-alkylamino peptoid homooligomers: solution phase synthesis and conformational investigation

• Maxime Pypec,
• Laurent Jouffret,
• Claude Taillefumier and
• Olivier Roy

Beilstein J. Org. Chem. 2022, 18, 845–854, doi:10.3762/bjoc.18.85

• 1c, respectively (Scheme 2). The N-Fmoc-protected acid partner 1c was readily prepared from 1a under standard conditions. After a few unsuccessful attempts of coupling using the azabenzotriazole-based coupling reagent HATU [42] or via the formation of an acid chloride with thionyl chloride, we turned

Efficient synthesis of ethyl 2-(oxazolin-2-yl)alkanoates via ethoxycarbonylketene-induced electrophilic ring expansion of aziridines

• Yelong Lei and
• Jiaxi Xu

Beilstein J. Org. Chem. 2022, 18, 70–76, doi:10.3762/bjoc.18.6

• diastereomeric products 3 were obtained. Compared with previously reported methods, our current method is more convenient and low cost without any activators (such as thionyl chloride, sulfonyl chlorides, NBS, electrophiles, and radical initiators) and catalysts. The current synthetic strategy is a clean

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

• -Hydroxyoxathiolane intermediate 56a was isolated in a DKR procedure by Whitehead and co-workers (Scheme 38) [55]. Further, 5-chlorooxathiolane 56 was isolated from chlorination reaction of 5-hydroxyoxathiolane 56a using thionyl chloride in presence of catalytic DMF and dichloromethane solvent. This further reacted

Double-headed nucleosides: Synthesis and applications

• Vineet Verma,
• Jyotirmoy Maity,
• Vipin K. Maikhuri,
• Ritika Sharma,
• Himal K. Ganguly and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2021, 17, 1392–1439, doi:10.3762/bjoc.17.98

• using thionyl chloride in dichloromethane, followed by the treatment of the product with N3-benzoylthymine under basic conditions (K2CO3 in DMF) to produce the nucleoside 18. The removal of the tert-butyldimethylsilyl group from nucleoside 18, followed by dimethoxytritylation at the primary hydroxy and

N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

• Joseane A. Mendes,
• Paulo R. R. Costa,
• Miguel Yus,
• Francisco Foubelo and
• Camilla D. Buarque

Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86

• , because of the influence of the bulky tert-butyl in the most stable conformation of the sulfinyl imine (Scheme 30). The authors also demonstrated the synthetic utility of compounds 100. Their reaction with thionyl chloride in methanol produced removal of the sulfinyl group and formation of the

Stereoselective syntheses of 3-aminocyclooctanetriols and halocyclooctanetriols

• Emine Salamci and
• Yunus Zozik

Beilstein J. Org. Chem. 2021, 17, 705–710, doi:10.3762/bjoc.17.59

• oxidation of the double bond gave diacetatediol 7 [33]. Treatment of diacetatediol 7 with thionyl chloride in pyridine gave the corresponding cyclic sulfite 8 in 95% yield (Scheme 1). Oxidation of the cyclic sulfite 8 with sodium periodate in the presence of ruthenium trichloride provided the corresponding

Synthetic strategies of phosphonodepsipeptides

• Jiaxi Xu

Beilstein J. Org. Chem. 2021, 17, 461–484, doi:10.3762/bjoc.17.41

• ) were modest inhibitors. The synthesis started from diphenyl N-Cbz-1-aminoalkylphosphonates 11 (Scheme 1). They were transformed to dimethyl esters via transesterification and further to monomethyl esters 12 via basic hydrolysis. After chlorination with thionyl chloride, the monomethyl esters 12 were

• carboxypeptidase A. Synthesis of α-phosphonodepsidipeptides containing enantiopure hydroxy ester as VanX inhibitors. Synthesis of α-phosphonodepsidipeptides as VanX inhibitors. Synthesis of optically active α-phosphonodepsidipeptides as VanX inhibitors. The synthesis of phosphonodepsipeptides through a thionyl

• chloride-catalyzed esterification of N-Cbz aminoalkylphosphonic acids 32 and 4-nitrobenyl 2-hydroxyalkanoates 33. Synthesis of α-phosphinodipeptidamide as a hapten. Synthesis of α-phosphonodepsioctapeptide 41. Synthesis of phosphonodepsipeptides via an in situ-generated phosphonochloridate. Synthesis of α

Supramolecular polymers with reversed viscosity/temperature profile for application in motor oils

• Jan-Erik Ostwaldt,
• Christoph Hirschhäuser,
• Stefan K. Maier,
• Carsten Schmuck and
• Jochen Niemeyer

Beilstein J. Org. Chem. 2021, 17, 105–114, doi:10.3762/bjoc.17.11

• cyclisation. Thus, all compounds feature a central BINAM unit, which is connected to the BUs (GCP or ACP) via a propionamide linker [29]. The synthesis of compound 1 was carried out starting from BINAM by coupling with GCP derivate 5 [12][13] after activation with thionyl chloride (see Figure 3). Deprotection

Hierarchically assembled helicates as reaction platform – from stoichiometric Diels–Alder reactions to enamine catalysis

• David Van Craen,
• Jenny Begall,
• Johannes Großkurth,
• Leonard Himmel,
• Oliver Linnenberg,
• Elisabeth Isaak and
• Markus Albrecht

Beilstein J. Org. Chem. 2020, 16, 2338–2345, doi:10.3762/bjoc.16.195

• the amino alcohols 10a–d were protected with a Boc group [42][43]. Esterification of the protected alcohols 11a–d [33][44] with 2,3-dioxosulfinylbenzoyl chloride obtained from 2,3-dihydroxybenzoic acid and thionyl chloride afforded the N-Boc-substituted catechol ligands 12a–d [33][36]. They were

Fluorinated phenylalanines: synthesis and pharmaceutical applications

• Laila F. Awad and
• Mohammed Salah Ayoup

Beilstein J. Org. Chem. 2020, 16, 1022–1050, doi:10.3762/bjoc.16.91

• synthesis from ethyl trifluoropyruvate hemiketal The reaction of ethyl trifluoropyruvate hemiketal 130 with thionyl chloride in pyridine afforded the chlorinated derivative 131, which upon treatment with zinc powder in DMF, afforded the dihalogenated olefin 132. The substitution of one fluorine atom in 132

Pd-catalyzed asymmetric Suzuki–Miyaura coupling reactions for the synthesis of chiral biaryl compounds with a large steric substituent at the 2-position

• Yongsu Li,
• Bendu Pan,
• Xuefeng He,
• Wang Xia,
• Yaqi Zhang,
• Hao Liang,
• Chitreddy V. Subba Reddy,
• Rihui Cao and
• Liqin Qiu

Beilstein J. Org. Chem. 2020, 16, 966–973, doi:10.3762/bjoc.16.85

• : A round bottom flask (100 mL) was charged with 2-bromo-3-methylbenzoic acid (2.0 g, 1.0 equiv) and SOCl2 (16 mL) was added at room temperature. Then, the reaction mixture was refluxed at 80 °C for 2 h. After completion of the reaction, the excess thionyl chloride was removed by evaporation using a

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions

• Pezhman Shiri and
• Jasem Aboonajmi

Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52

• ” products by this new catalyst was successfully accomplished. To synthesize the catalyst, first, GO–COCl was created by the reaction of GO with thionyl chloride in DMF at reflux for 24 h. Then, the resulting GO–COCl compound was treated with 1,7-diaminoheptane to afford amino-modified graphene oxide (GO–CO–NH2

Chemical tuning of photoswitchable azobenzenes: a photopharmacological case study using nicotinic transmission

• Lorenzo Sansalone,
• Jun Zhao,
• Matthew T. Richers and
• Graham C. R. Ellis-Davies

Beilstein J. Org. Chem. 2019, 15, 2812–2821, doi:10.3762/bjoc.15.274

• maleimide using hydroxymethylation with formaldehyde, followed by treatment with thionyl chloride to give a chloromethyl intermediate, which was reacted in situ with maleimide to give 1 in 6% overall yield. Crucially, photochrome 1 also maintained the near-ideal photochemical properties of Hecht’s 4FABs [12

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

• with thionyl chloride followed by derivatization with (S)-(−)-phenylalanine methyl ester. The applicability of this modified electrode [(S)-CelPheM] was tested by using it as a cathode for the electrochemical reduction of 4-acetylpyridine (1). GC analysis of the product indicated the formation of the

Synthesis of a novel category of pseudo-peptides using an Ugi three-component reaction of levulinic acid as bifunctional substrate, amines, and amino acid-based isocyanides

• Maryam Khalesi,
• Azim Ziyaei Halimehjani and
• Jürgen Martens

Beilstein J. Org. Chem. 2019, 15, 852–857, doi:10.3762/bjoc.15.82

• esterification of the α-amino acid using thionyl chloride in methanol as reagent and solvent. The second reaction is the formylation of the corresponding amino acid ester salt with ethyl formate in the presence of NaHCO3. Finally, the formamide group was transformed to the corresponding isocyanide 3 using POCl3

Azologization of serotonin 5-HT₃ receptor antagonists

• Karin Rustler,
• Galyna Maleeva,
• Piotr Bregestovski and
• Burkhard König

Beilstein J. Org. Chem. 2019, 15, 780–788, doi:10.3762/bjoc.15.74

• (18) [75]. Activation using thionyl chloride [76] afforded the acid chloride 26 and allowed amide-bond formation [77] for the generation of 28 (Scheme 6). Photochromic properties The investigation of the photochromic properties of the potential 5-HT3R antagonists 5a, 5b, 12a, 16a–d, 23, and 28 was

Chiral bisoxazoline ligands designed to stabilize bimetallic complexes

• Deepankar Das,
• Rudrajit Mal,
• Nisha Mittal,
• Zhengbo Zhu,
• Thomas J. Emge and
• Daniel Seidel

Beilstein J. Org. Chem. 2018, 14, 2002–2011, doi:10.3762/bjoc.14.175

• shown in Scheme 3. In addition to the change in geometry, compound 25-H3 is a potentially trianionic as opposed to a dianionic ligand. A reaction of pyrazole-3,5-diacyl chloride 23, obtained by treatment of pyrazol-3,5-dicarboxylic acid with thionyl chloride, with aminophenyloxazoline 24 [59] provided

First thia-Diels–Alder reactions of thiochalcones with 1,4-quinones

• Grzegorz Mlostoń,
• Katarzyna Urbaniak,
• Paweł Urbaniak,
• Anna Marko,
• Anthony Linden and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2018, 14, 1834–1839, doi:10.3762/bjoc.14.156

• treatment of quinizarine with thionyl chloride according to the protocol described in [27]. Thiochalcones 1a–d were prepared according to our protocol reported in an earlier publication [16]. General procedure: A solution of 1 mmol of the corresponding thiochalcone 1 and 1 mmol of the 1,4-quinone 2 in 1 mL

Design, synthesis and structure of novel G-2 melamine-based dendrimers incorporating 4-(n-octyloxy)aniline as a peripheral unit

• Cristina Morar,
• Pedro Lameiras,
• Attila Bende,
• Gabriel Katona,
• Emese Gál and
• Mircea Darabantu

Beilstein J. Org. Chem. 2018, 14, 1704–1722, doi:10.3762/bjoc.14.145

• )alkanoic acid-based tripodal melamines into the corresponding tri acid chlorides (not depicted in Scheme 4) followed typical procedures (in refluxing thionyl chloride with SO2 and HCl generation), a long reaction time (up to 24 h, as determined by HRMS monitoring) was mandatory for this transformation to

An unusual thionyl chloride-promoted C−C bond formation to obtain 4,4'-bipyrazolones

• Gernot A. Eller,
• Gytė Vilkauskaitė,
• Algirdas Šačkus,
• Vytas Martynaitis,
• Ashenafi Damtew Mamuye,
• Vittorio Pace and
• Wolfgang Holzer

Beilstein J. Org. Chem. 2018, 14, 1287–1292, doi:10.3762/bjoc.14.110

• of 5-hydroxypyrazole-4-carboxylates in refluxing thionyl chloride. The obtained diesters can be transformed into the corresponding 4,4'-bipyrazoles via alkaline hydrolysis and subsequent decarboxylation. Detailed NMR spectroscopic investigations (1H, 13C, 15N) were undertaken with all products

• prepared. Moreover, the structure of a representative 5,5'-dioxo-4,4'-bipyrazole-4,4'-dicarboxylate was confirmed by X-ray crystal structure analysis. Keywords: dimerization; NMR (1H; 13C; 15N); pyrazolones; thionyl chloride; X-ray structure analysis; Introduction Many biologically active substances

• = H, R = Et) with POCl3 left the starting material untouched, similarly by treatment of 1a with oxalyl chloride no conversion occurred (Scheme 2). In contrast, treatment of 1a with excessive thionyl chloride at reflux temperature resulted in a defined reaction product which, however, could not be the

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