(Bio)isosteres of ortho- and meta-substituted benzenes

• H. Erik Diepers and
• Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

• nitrogen-substituted 1,5-BCHeps 141a–d through a photoredox-catalysed aminoalkylation with amines 140 and iodonium dicarboxylates 139 (Scheme 15A) [27]. Both Anderson and Uchiyama also reported the synthesis of chalcogen- and tin-substituted 1,5-BCHeps 145a–f from [3.1.1]propellane (Scheme 15B) [27][47][60

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

• conversion in situ, triggered by thermal activation, photoirradiation or redox control. Beside well-established reactions involving the elimination of carbon-based small molecules, i.e., retro-Diels–Alder and decarbonylation processes, the late-stage extrusion of chalcogen fragments has emerged as a highly

• ultimate elimination of chalcogen fragments upon thermal activation, photoirradiation and electron exchange. Keywords: arenes; chalcogens; extrusion; fused-ring systems; precursor approach; Introduction π-Conjugated polycyclic compounds (π-CPCs), including polycyclic aromatic hydrocarbons and their

• strategies in line with the “precursor approach” have been recently reported, in which chalcogen-containing precursors undergo a ring contraction combined with the extrusion of a chalcogen fragment in the ultimate step. In view of the diversity of π-conjugated polycyclic structures potentially accessible via

Transition-metal-catalyzed C–H bond activation as a sustainable strategy for the synthesis of fluorinated molecules: an overview

• Louis Monsigny,
• Floriane Doche and
• Tatiana Besset

Beilstein J. Org. Chem. 2023, 19, 448–473, doi:10.3762/bjoc.19.35

• [49] have been already reported, these reactions will not be included. Review I. Transition-metal-catalyzed directed C–chalcogen bond formation (C–S, C–Se) by C–H bond activation In the past decade, particular attention has been paid to the development of new methodologies for the incorporation of

Supramolecular approaches to mediate chemical reactivity

• Pablo Ballester,
• Qi-Qiang Wang and
• Carmine Gaeta

Beilstein J. Org. Chem. 2022, 18, 1463–1465, doi:10.3762/bjoc.18.152

• hydrogen bonding interactions play a pivotal role in catalysis. More recently, halogen bonding interactions have been used as a novel tool to catalyze a wide variety of processes. Other nonclassical interactions, including anion-, chalcogen-, and pnictogen bonding, have also been exploited for the design

• of novel supramolecular catalysts. In their contribution Wang and co-workers [17] reported an interesting example of chalcogen bonding catalysis approach for the synthesis of calix[4]pyrrole macrocycles. The Se···O=C chalcogen bonding interactions between a selenide-based catalyst and the carbonyl

A Se···O bonding catalysis approach to the synthesis of calix[4]pyrroles

• Qingzhe Tong,
• Zhiguo Zhao and
• Yao Wang

Beilstein J. Org. Chem. 2022, 18, 325–330, doi:10.3762/bjoc.18.36

• Qingzhe Tong Zhiguo Zhao Yao Wang School of Chemistry and Chemical Engineering, Key Laboratory of the Colloid and Interface Chemistry, Shandong University, Jinan 250100, China 10.3762/bjoc.18.36 Abstract Described herein is a chalcogen bonding catalysis approach to the synthesis of calix[4

• ]pyrrole derivatives. The Se···O bonding interactions between selenide catalysts and ketones gave rise to the catalytic activity in the condensation reactions between pyrrole and ketones, leading to the generation of calix[4]pyrrole derivatives in moderate to high yields. This chalcogen bonding catalysis

• . Keywords: calix[4]pyrrole; chalcogen bonding; ketones; Se···O bonding interactions; supramolecular catalysis; Introduction Noncovalent catalysis has been established as one of the fundamental concepts in organic synthesis that enables achieving numerous chemical transformations [1]. Among these

New advances in asymmetric organocatalysis

• Radovan Šebesta

Beilstein J. Org. Chem. 2022, 18, 240–242, doi:10.3762/bjoc.18.28

• transformations using chiral Brønsted acids, Brønsted base, and hydrogen bond donors. Recently noncovalent activation continues to expand into other types of weak attractive interactions such as halogen and chalcogen bonds. Not surprisingly, all activation modes allow further expansion and diversification via a

Catalyzed and uncatalyzed procedures for the syntheses of isomeric covalent multi-indolyl hetero non-metallides: an account

• Ranadeep Talukdar

Beilstein J. Org. Chem. 2021, 17, 2102–2122, doi:10.3762/bjoc.17.137

• only, thus stating the requirement of acid for this Fischer indole synthesis. Elemental sulfur has also been utilized in preparing bis(indol-3-yl)sulfides under transition-metal compound catalyzed spontaneous oxidation of the central chalcogen atom. Such reactions were carried out by Shibahara (2014

Identification of volatiles from six marine Celeribacter strains

• Anuj Kumar Chhalodia,
• Jan Rinkel,
• Dorota Konvalinkova,
• Jörn Petersen and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2021, 17, 420–430, doi:10.3762/bjoc.17.38

• were obtained by the Michael addition of NaSMe to ethyl propiolate (45), yielding a mixture of stereoisomers inseparable by silica gel column chromatography (92%). The major stereoisomer was found to be (Z)-42 (dr 94:6), whose preferred formation may be a result of a chalcogen–chalcogen interaction

Exploring the possibility of using fluorine-involved non-conjugated electron-withdrawing groups for thermally activated delayed fluorescence emitters by TD-DFT calculation

• Dongyang Chen and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2021, 17, 210–223, doi:10.3762/bjoc.17.21

• is five times higher than 2CzSF5, and 5CzSF5 possesses the second highest |VSOC|2 value as 0.718 cm−2, which is more than thirteen times higher than 2CzSF5. The higher |VSOC|2 values of 2CzSCF3/5CzSCF3 and 2CzSF5/5CzSF5 can be ascribed to the presence of the relatively heavier chalcogen, which has

Chiral anion recognition using calix[4]arene-based ureido receptors in a 1,3-alternate conformation

• Tereza Horáčková,
• Jan Budka,
• Vaclav Eigner,
• Wen-Sheng Chung,
• Petra Cuřínová and
• Pavel Lhoták

Beilstein J. Org. Chem. 2020, 16, 2999–3007, doi:10.3762/bjoc.16.249

• completed by the close contacts between carbonyl oxygen atoms (of the urea group) and S atoms (of DMSO), indicating possible chalcogen interactions [47][48], and the C=O···S=O distances were 3.269 and 3.308 Å (Figure 3a). The molecular packing was further strengthened by the π–π interactions of the p

• -acetylphenylalaninate. Design of chiral calix[4]arene-based receptors for anions. X-ray structure of 4a: (a) Top view into the cavity. (b) Side view of the same cavity. X-ray structure of 7a: (a) Hydrogen bonding interactions (black) in a dimeric motif, chalcogen interactions are shown in green. (b) π–π interactions in

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

Models of necessity

• Timothy Clark and
• Martin G. Hicks

Beilstein J. Org. Chem. 2020, 16, 1649–1661, doi:10.3762/bjoc.16.137

• generally approached the subject. Specific potential functions are added to empirical force fields for hydrogen [87] or halogen [88] bonding. However, given that researchers have been busily defining additional non-covalent interactions such as tetrel [89], pnictogen [90] and chalcogen bonding [91], this

Copper-promoted/copper-catalyzed trifluoromethylselenolation reactions

• Clément Ghiazza and
• Anis Tlili

Beilstein J. Org. Chem. 2020, 16, 305–316, doi:10.3762/bjoc.16.30

• ; Introduction In recent years, the incorporation of fluorine or fluorinated motifs into organic molecules has gained widespread interest. This is mainly due to the new properties associated with the introduction of these modifications. In particular, chalcogen trifluoromethyl motifs are of prime interest since

• they confer very high lipophilicity [1][2]. In this context, transition-metal catalysis plays a key role in the formation of carbon–chalcogen trifluoromethyl bonds. Major advances have been made in the last ten years especially for C–OCF3 [3][4][5] and C–SCF3 [6][7][8] bond-forming processes. Today

• usually contain copper–chalcogen trifluoromethyl σ-bonds. Likewise, the research on new methods enabling the incorporation of SeCF3 has continuously been growing and today, a plethora of strategies have been reported [10][11]. Therein, the design of new catalysts and reagents is a key factor to foster the

1,2,3-Triazolium macrocycles in supramolecular chemistry

• Mastaneh Safarnejad Shad,
• Pulikkal Veettil Santhini and
• Wim Dehaen

Beilstein J. Org. Chem. 2019, 15, 2142–2155, doi:10.3762/bjoc.15.211

• receptors for molecular recognition of anionic species, pH sensors, mechanically interlocked molecules, molecular machines, and molecular reactors. Keywords: anion recognition; catenane; chalcogen bonding; click reaction; molecular reactor; hydrogen bonding; pH sensor; rotaxane; supramolecular; 1,2,3

• -triazole units to more electrophilic 1,2,3-triazolium units by influencing both hydrogen bonding-like and anion–π interactions. Moreover, halogen bond (XB) and chalcogen bond (ChB) interactions (see Figure 1) also been applied for the selective detection of anions by exchanging C5–H protons with halogens

• -position of the triazoles (triazolium), and nucleophilic substitution of halogen can be used to introduce chalcogens (Se, Te). Thus, the corresponding triazolium macrocycles can take advantage respectively of halogen and chalcogen bonding as part of the molecular recognition (vide infra). In this review

Synthesis of benzo[d]imidazo[2,1-b]benzoselenoazoles: Cs₂CO₃-mediated cyclization of 1-(2-bromoaryl)benzimidazoles with selenium

• Mio Matsumura,
• Yuki Kitamura,
• Arisa Yamauchi,
• Yoshitaka Kanazawa,
• Yuki Murata,
• Tadashi Hyodo,
• Kentaro Yamaguchi and
• Shuji Yasuike

Beilstein J. Org. Chem. 2019, 15, 2029–2035, doi:10.3762/bjoc.15.199

• conditions for the cyclization of a chalcogen with 1-(2-bromophenyl)benzimidazole (1a). Table 1 shows the results from the screening of additives, solvents, and chalcogens. Since most of these types of reactions require a transition metal catalyst such as a copper reagent [14][15][16], the reaction between

• 1,2-DCE resulted in inefficient reactions (Table 1, entries 2 and 11–15). Under aerobic conditions, a significant decrease in the yield of product 2a was observed (Table 1, entry 16). We also attempted the cyclization of 1-(2-bromophenyl)benzimidazoles 1a using other chalcogen powders. However, the

• . Cyclization of 1-(2-bromophenyl)benzimidazoles with chalcogen elements.a Absorption spectroscopy dataa. Supporting Information Supporting Information File 401: Experimental details and analytical data, copies of absorption and NMR spectra. Supporting Information File 402: X-ray crystal structure of 2a

Glycosylation reactions mediated by hypervalent iodine: application to the synthesis of nucleosides and carbohydrates

• Yuichi Yoshimura,
• Hideaki Wakamatsu,
• Yoshihiro Natori,
• Yukako Saito and
• Noriaki Minakawa

Beilstein J. Org. Chem. 2018, 14, 1595–1618, doi:10.3762/bjoc.14.137

• unique biological activity of 4’-thionucleosides triggered the synthesis of their chalcogen isosters, 4’-selenonucleosides, the activity of which were reported. The first synthesis of 4’-selenonucleosides was reported by Jeong and co-workers in 2008 [48][49]. As in the case of the 4’-thioribonucleoside

Mechanochemical synthesis of small organic molecules

• Tapas Kumar Achar,
• Anima Bose and
• Prasenjit Mal

Beilstein J. Org. Chem. 2017, 13, 1907–1931, doi:10.3762/bjoc.13.186

• have shown that the reaction followed a radical pathway [170]. C–Chalcogen bond formation Ranu and co-workers reported carbon–chalcogen (C–S, C–Se, C–Te) bond formation from aryldiazonium tetrafluoroborate (1 equiv), diaryl chalocogenide (0.5 equiv) in a stainless steel jar at 600 rpm for 15 min. They

• ]. Mechanochemical synthesis of azacenes [169]. Mechanochemical oxidative C-P bond formation [170]. Mechanochemical C–chalcogen bond formation [171]. Solvent-free synthesis of an organometallic complex. Selective examples of mechano-synthesis of organometallic complexes. a) Halogenation reaction of Re-complexes [175

Correlation of surface pressure and hue of planarizable push–pull chromophores at the air/water interface

• Frederik Neuhaus,
• Fabio Zobi,
• Gerald Brezesinski,
• Marta Dal Molin,
• Stefan Matile and
• Andreas Zumbuehl

Beilstein J. Org. Chem. 2017, 13, 1099–1105, doi:10.3762/bjoc.13.109

• introduced. The structure of such a "flipper" probe is depicted in Figure 1 [6][7][8][9]. Without going into details, the two dithienothiophene flippers are twisted out of planarity by chalcogen bond repulsion between the methyl groups and the endocyclic sulfurs next to the mechanosensitive bond [9

N-Propargylamines: versatile building blocks in the construction of thiazole cores

• S. Arshadi,
• E. Vessally,
• L. Edjlali,
• R. Hosseinzadeh-Khanmiri and
• E. Ghorbani-Kalhor

Beilstein J. Org. Chem. 2017, 13, 625–638, doi:10.3762/bjoc.13.61

• -2-ylamides 54 in good yields (Scheme 16a). The mechanism for this cyclization as proposed by the authors is depicted in Scheme 16b [98]. Following this work, the Čikotienė group studied the metal-free halogen, chalcogen, or oxocarbenium ion-mediated cyclization of a series of N-propargylthioureas 55

Nucleophilic displacement reactions of 5′-derivatised nucleosides in a vibration ball mill

• Olga Eguaogie,
• Patrick F. Conlon,
• Francesco Ravalico,
• Jamie S. T. Sweet,
• Thomas B. Elder,
• Louis P. Conway,
• Marc E. Lennon,
• David R. W. Hodgson and
• Joseph S. Vyle

Beilstein J. Org. Chem. 2017, 13, 87–92, doi:10.3762/bjoc.13.11

• corresponding 5′-selenocyanates in variable yields over the course of between one and eleven hours thereby avoiding the preparation and use of hygroscopic tetrabutylammonium salts. Keywords: ball mill; chalcogen; mechanochemistry; nucleophilic substitution; nucleoside; Introduction Nucleophilic displacement

O-Alkylated heavy atom carbohydrate probes for protein X-ray crystallography: Studies towards the synthesis of methyl 2-O-methyl-L-selenofucopyranoside

• Roman Sommer,
• Dirk Hauck,
• Annabelle Varrot,
• Anne Imberty,
• Markus Künzler and
• Alexander Titz

Beilstein J. Org. Chem. 2016, 12, 2828–2833, doi:10.3762/bjoc.12.282

• activated due to their enhanced reactivity in the presence of other chalcogen-containing glycosides such as O- or S-glycosides. By exploiting these properties, one-pot multi-step glycosylation reactions have been developed recently [10][11]. Natural selenosugars, such as methylseleno N-acetyl-β-D

Star-shaped tetrathiafulvalene oligomers towards the construction of conducting supramolecular assembly

• Masahiko Iyoda and
• Masashi Hasegawa

Beilstein J. Org. Chem. 2015, 11, 1596–1613, doi:10.3762/bjoc.11.175

• doping of 15a with iodine and bromine vapors afforded black conducting complexes (σrt = 1.1 × 10−4 and 1.5 × 10−4 S cm−1, respectively). For conjugated TTF dimers linked by π-systems or chalcogen atoms, intramolecular through-bond and/or through-space interactions can be expected between two TTF parts

Synthesis and characterization of the cyanobenzene-ethylenedithio-TTF donor

• Sandrina Oliveira,
• Dulce Belo,
• Isabel C. Santos,
• Sandra Rabaça and
• Manuel Almeida

Beilstein J. Org. Chem. 2015, 11, 951–956, doi:10.3762/bjoc.11.106

• between planar molecules that tend to be organized in the solid state as stacks or layers with their long axis parallel to each other. Second, the incorporation of additional sulfur and other chalcogen atoms in the molecular periphery to promote side intermolecular interactions along the molecular plane

Homolytic substitution at phosphorus for C–P bond formation in organic synthesis

• Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 1269–1277, doi:10.3762/bjoc.9.143

• position since they provide transformations unattainable by polar reactions. Homolytic substitution is a reaction in which a radical (R•) attacks a saturated atom (X) in a molecule with the liberation of a leaving radical (L•) from the atom (Scheme 2). Homolytic substitution at halogen and chalcogen atoms

Asymmetric synthesis of tertiary thiols and thioethers

• Jonathan Clayden and
• Paul MacLellan

Beilstein J. Org. Chem. 2011, 7, 582–595, doi:10.3762/bjoc.7.68

• greater steric bulk in the chalcogen substituent. 2.2.2 Lithiation and alkylation of thiocarbamates Hoppe and co-workers applied the observations of Hoffmann and Reich in comprehensive studies on configurationally stable α-lithiothiocarbamates. Stereoselective deprotonations of thiocarbamate 73 in the