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Artykuły w czasopismach na temat „Heteroatom Bond”

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Data publikacji: 6 września 2023

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1

Kotun, Stefan P., i Darryl D. DesMarteau. "Superacid-induced ring-opening reactions of fluorinated heterocycles". Canadian Journal of Chemistry 67, nr 11 (1.11.1989): 1724–28. http://dx.doi.org/10.1139/v89-265.

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HF/AsF5 and HF/SbF5 superacid mixtures react with fluorinated small-ring heterocycles such as 1,2-oxazetidines and oxetanes with consequent addition of HF to give alcohol and amine ring-opened products in high yield. Excess HF serves as solvent and reactant. Ring compounds containing both nitrogen and oxygen as heteroatoms protonate predominantly on nitrogen; a case with competing O-protonation arises in the case of a chloro-substituted oxazetidine. In general, rings containing two heteroatoms retain the heteroatom–heteroatom bond and it is a carbon–heteroatom bond that opens. The resulting OH and NH functional groups are not protonated and lost in the superacid medium due to the instability of the highly fluorinated cations that would be left behind. Most of the heterocycles react at or below room temperature, although the very weakly basic 2,2-bis(trifluoromethyl)-3,3,4,4-tetrafluorooxetane requires the stronger HF/SbF5 superacid system and more severe conditions. Keywords: superacids, hydrogen fluoride, ring opening, fluorinated oxazetidines, fluorinated oxetanes.

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2

Kadjo, François Kassi, Sopi Thomas Affi, Yao Silvère Diki N’guessan, Mamadou Guy-Richard Koné, Georges Stéphane Dembélé i Nahossé Ziao. "Theoretical Characterization of the Hydrogen Bonding Interaction Sites of Mycolactone C Using the ONIOM Method". Mediterranean Journal of Chemistry 11, nr 2 (26.04.2021): 185. http://dx.doi.org/10.13171/mjc02104261574mgrk.

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<p>In this work, the ONIOM method, recognized for its effectiveness on large molecules, was used to determine the geometric, energetic, and spectroscopic parameters of hydrogen bond interactions of mycolactone C. Mycolactone C; one of the most virulent forms of toxin, found in Africa and Australia. It has eight (08) oxygen heteroatoms which are all hybridized sp<sup>2</sup> and sp<sup>3</sup>. Using quantum chemistry methods, at the ONIOM level (B3LYP/6-311+G (d, p): AM1), we have determined the preferential binding sites of the hydrogen bonds in the eight mycolactone C oxygen heteroatoms studied. Analysis of the results revealed that the heteroatom O<sub>5</sub>sp<sup>2</sup> is the most suitable site for creating a strong hydrogen bond based on the geometric, energetic (free enthalpy of complexation), and spectroscopic (vibration frequency shifts) parameters. Identifying this O5sp2 heteroatom is a significant step forward in developing a methodology for eradicating the infection and the destructive effects of this toxin.</p>

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3

Yamamoto, Yuki, Qiqi Chen i Akiya Ogawa. "Diphenyl Diselenide-Assisted Radical Addition Reaction of Diphenyl Disulfide to Unsaturated Bonds upon Photoirradiation". Molecules 28, nr 6 (7.03.2023): 2450. http://dx.doi.org/10.3390/molecules28062450.

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The addition reaction of interelement compounds with heteroatom–heteroatom single bonds to unsaturated bonds under photoirradiation is an important method for the efficient and atom-economical construction of carbon–heteroatom bonds. However, in practice, the desired addition reaction is sometimes unable to proceed as expected due to the low efficiency of the desired addition reactions or the preferential polymerization of unsaturated compounds. In this study, by combining an interelement compound with homologous heteroatom compounds as a catalyst, we succeeded in suppressing the polymerization of the unsaturated compounds and in attaining a highly selective carbon–heteroatom bond formation through the desired addition reaction. In this paper, we have examined in detail whether such a “catalytic radical reaction” proceeds for unsaturated compounds and found that the dithiolation of some unsaturated compounds (i.e., vinylic ethers, styrenes, and isocyanides) could proceed with the assistance of (PhSe)2 under light. The developed methods in this study are expected to have strong implications in the fields of radical chemistry, heteroatom chemistry, synthetic organic chemistry, and catalyst chemistry as atom-economical methods for carbon–heteroatom bond formation.

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4

Correa, Arkaitz, Olga García Mancheño i Carsten Bolm. "Iron-catalysed carbon–heteroatom and heteroatom–heteroatom bond forming processes". Chemical Society Reviews 37, nr 6 (2008): 1108. http://dx.doi.org/10.1039/b801794h.

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5

Zou, Song, Sheng Wang i Chanjuan Xi. "ROTf-induced annulation of heteroatom reagents and unsaturated substrates leading to cyclic compounds". Royal Society Open Science 5, nr 11 (listopad 2018): 181389. http://dx.doi.org/10.1098/rsos.181389.

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The development of metal-free organic reactions is one of the hotspots in the synthesis of cyclic compounds. ROTf (alkyl trifluoromethanesulfonates), due to their good electrophilicity, are powerful alkylating reagents at heteroatoms such as nitrogen, oxygen, sulfur and phosphorus to induce an electrophilic centre for carbon–carbon or carbon–heteroatom bond formation. Inspired by this chemistry, a variety of research concentrating on heterocycles synthesis has been carried out. In this review, we mainly summarize the ROTf-induced annulation of heteroatom reagents such as nitriles, carbodiimides, azobenzenes, isothiocyanates, aldehydes, isocyanates and phosphaalkene with themselves or alkynes to afford cyclic compounds.

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6

Skalik, Joanna, Marek Koprowski, Ewa Różycka-Sokołowska i Piotr Bałczewski. "The hetero-Friedel-Crafts-Bradsher Cyclizations with Formation of Ring Carbon-Heteroatom (P, S) Bonds, Leading to Organic Functional Materials". Materials 13, nr 21 (23.10.2020): 4751. http://dx.doi.org/10.3390/ma13214751.

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The interest in functional materials possessing improved properties led to development of new methods of their synthesis, which allowed to obtain new molecular arrangements with carbon and heteroatom motifs. Two of the classical reactions of versatile use are the Friedel-Crafts and the Bradsher reactions, which in the new heteroatomic versions allow to replace ring carbon atoms by heteroatoms. In the present work, we review methods of synthesis of C–S and C–P bonds utilizing thia- and phospha-Friedel-Crafts-Bradsher cyclizations. Single examples of C–As and lack of C–Se bond formation, involving two of the closest neighbors of P and S in the periodic table, have also been noted. Applications of the obtained π-conjugated molecules, mainly as semiconducting materials, flame retardants, and resins hardeners, designed on the basis of five- and six-membered cyclic molecules containing ring phosphorus and sulfur atoms, are also included. This comprehensive review covers literature up to August 2020.

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7

Waldman, Abraham J., Tai L. Ng, Peng Wang i Emily P. Balskus. "Heteroatom–Heteroatom Bond Formation in Natural Product Biosynthesis". Chemical Reviews 117, nr 8 (4.04.2017): 5784–863. http://dx.doi.org/10.1021/acs.chemrev.6b00621.

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8

Zybill, Christian. "The silicon heteroatom bond". Inorganica Chimica Acta 202, nr 1 (grudzień 1992): 119–20. http://dx.doi.org/10.1016/s0020-1693(00)85362-1.

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9

Eaborn, Colin. "The silicon-heteroatom bond". Journal of Organometallic Chemistry 427, nr 3 (kwiecień 1992): C41. http://dx.doi.org/10.1016/0022-328x(92)80084-b.

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10

Cai, Xiao-Hua, Meng-Zhi Yang i Bing Xie. "Recent Investigations on the Functionalizations of C(sp3)-H Bonds Adjacent to a Heteroatom". Letters in Organic Chemistry 16, nr 10 (23.08.2019): 779–801. http://dx.doi.org/10.2174/1570178616666190123131353.

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The selective functionalization of unactivated C(sp3)-H bonds has been regarded as an efficient and atom-economical approach for the formation of carbon-carbon or carbon-heteroatom bonds in modern organic synthesis. Especially, the oxidative activation of C(sp3)–H bonds adjacent to a heteroatom exhibits quite significant features in synthetic chemistry. For example, the direct functionalizations of amines, amides and ethers present important alternative tactics for the synthesis of various novel and useful molecules from simple starting materials. Many remarkable achievements in the area had continuously been made in the past decades. Here we reviewed recent investigations on the transformations of C(sp3)-H bond adjacent to a heteroatom.

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11

Tanaka, Masato, i Ruimao Hua. "Addition reactions of heteroatom-COX (X = OR, NR2, COOR) species with alkynes". Pure and Applied Chemistry 74, nr 1 (1.01.2002): 181–86. http://dx.doi.org/10.1351/pac200274010181.

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Heteroatom-COX species where the heteroatom is Cl, S, or Sn and X is alkoxy, amino, or alkoxycarbonyl group were found to add to the triple bond of alkynes regio- and stereoselectively in the presence of Rh, Pd, or Ni catalyst. Scope and limitation of these synthetic reactions were disclosed. Mechanistic study revealed that oxidative addition of these heteroatom-COX bonds readily took place and the resulting adducts were isolable and characterized by X-ray diffraction analysis. Synthetic applications of the catalytic reactions were also demonstrated.

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12

Sarkar, Rajib, i Chhanda Mukhopadhyay. "Carbon-Hydrogen Bond Functionalization in Aqueous Medium: A Brief Review". Current Green Chemistry 6, nr 3 (18.12.2019): 184–97. http://dx.doi.org/10.2174/2213346106666191019120048.

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In the last few decades, considerable research has led to the introduction of selective and efficient green as well as sustainable synthetic methods of functionalization of carbon-hydrogen bonds to form new carbon-carbon and carbon-heteroatom bonds. In this emerging field, significant development has been attained under various environmentally benign conditions including aqueous medium. In this review, we have summarized the current development of C-H functionalization carried out in an aqueous medium and its synthetic applications according to carbon-carbon and carbon-heteroatom bond formations under green conditions.

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13

Wang, Zhong-Xia, i Bo Yang. "Chemical transformations of quaternary ammonium salts via C–N bond cleavage". Organic & Biomolecular Chemistry 18, nr 6 (2020): 1057–72. http://dx.doi.org/10.1039/c9ob02667c.

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14

Sharma, Mitu, Bhupendra Adhikari, Raymond Femi Awoyemi, Amanda M. Perkins, Alison K. Duckworth, Bruno Donnadieu, David O. Wipf, Sean L. Stokes i Joseph P. Emerson. "Copper(II) NHC Catalyst for the Formation of Phenol from Arylboronic Acid". Chemistry 4, nr 2 (7.06.2022): 560–75. http://dx.doi.org/10.3390/chemistry4020040.

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Arylboronic acids are commonly used in modern organic chemistry to form new C–C and C–heteroatom bonds. These activated organic synthons show reactivity with heteroatoms in a range of substrates under ambient oxidative conditions. This broad reactivity has limited their use in protic, renewable solvents like water, ethanol, and methanol. Here, we report our efforts to study and optimize the activation of arylboronic acids by a copper(II) N-heterocyclic carbene (NHC) complex in aqueous solution and in a range of alcohols to generate phenol and aryl ethers, respectively. The optimized reactivity showcases the ability to make targeted C–O bonds, but also identifies conditions where water and alcohol activation could be limiting for C–C and C–heteroatom bond-forming reactions. This copper(II) complex shows strong reactivity toward arylboronic acid activation in aqueous medium at ambient temperature. The relationship between product formation and temperature and catalyst loading are described. Additionally, the effects of buffer, pH, base, and co-solvent are explored with respect to phenol and ether generation reactions. Characterization of the new copper(II) NCN-pincer complex by X-ray crystallography, HR-MS, cyclic voltammetry, FT-IR and UV-Vis spectral studies is reported.

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15

Boylan, Amy, Thien S. Nguyen, Brian J. Lundy, Jian-Yuan Li, Ravikrishna Vallakati, Sasha Sundstrom i Jeremy A. May. "Rate Dependence on Inductive and Resonance Effects for the Organocatalyzed Enantioselective Conjugate Addition of Alkenyl and Alkynyl Boronic Acids to β-Indolyl Enones and β-Pyrrolyl Enones". Molecules 26, nr 6 (14.03.2021): 1615. http://dx.doi.org/10.3390/molecules26061615.

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Two key factors bear on reaction rates for the conjugate addition of alkenyl boronic acids to heteroaryl-appended enones: the proximity of inductively electron-withdrawing heteroatoms to the site of bond formation and the resonance contribution of available heteroatom lone pairs to stabilize the developing positive charge at the enone β-position. For the former, the closer the heteroatom is to the enone β-carbon, the faster the reaction. For the latter, greater resonance stabilization of the benzylic cationic charge accelerates the reaction. Thus, reaction rates are increased by the closer proximity of inductive electron-withdrawing elements, but if resonance effects are involved, then increased rates are observed with electron-donating ability. Evidence for these trends in isomeric substrates is presented, and the application of these insights has allowed for reaction conditions that provide improved reactivity with previously problematic substrates.

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16

Grama, Lavinia, F. Boda, A. S. Gaz Florea, A. Curticăpean i Daniela-Lucia Muntean. "The UV and IR Comparative Spectrophotometric Study of Some Saturated and Lacunary Polyoxometalates". Acta Medica Marisiensis 60, nr 3 (1.06.2014): 84–88. http://dx.doi.org/10.2478/amma-2014-0017.

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Abstract Objectives: The polyoxometalates are a class of inorganic compounds with controllable shapes and sizes, and with excellent properties that make them attractive for various applications. This study is aimed at the comparative UV and IR spectra of Keggin type polyoxometalates. Methods: Compounds under (UV and IR) investigations were divided into several groups to highlight similarities between compounds or classes of compounds for the same category. There are four types of saturated Keggin structures and six lacunar compounds included in this study. The study begins with the UV investigations on aqueous solutions with 10-5 M concentration for these compounds. IR spectra were recorded as KBr pressed pellets. Results: The UV spectras presents large strong peaks between 185-195 nm corresponding to W = Od bonds, between 251-268 nm for W-O-W bridge bonds, depending on heteroatom types (As, Sb). The unsaturated cryptand ligand having Co2+ coordinated presents the most intense peak, due to the involvement of oxygen atoms from terminal W = Od coordinative bonds with high electronic densities in coordination of W-O-Co bond. The IR spectra present many peaks that are associated as follows: for terminal bonds W = Od, 955-970 cm-1; for W-OW bridging bonds, 790-910 cm-1; for W-O-As/Sb bonds to heteroatom, 690-760 cm-1. Vibrations of the bonds between heteroatoms and oxygen (As/Sb-O) appear around 620-660 cm-1. Conclusions: Similarities appear from the recorded spectra, between compounds of the same class, by category association. Very fine displacements of peaks that occur explain the influence of heteroatoms, addenda atoms or coordinated cations.

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17

Daoust, Benoit, Nicolas Gilbert, Paméla Casault, François Ladouceur i Simon Ricard. "1,2-Dihaloalkenes in Metal-Catalyzed Reactions". Synthesis 50, nr 16 (9.07.2018): 3087–113. http://dx.doi.org/10.1055/s-0037-1610174.

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1,2-Dihaloalkenes readily undergo simultaneous or sequential difunctionalization through transition-metal-catalyzed reactions, which makes them attractive building blocks for complex unsaturated motifs. This review summarizes recent applications of such transformations in C–C and C–heteroatom bond forming processes. The facile synthesis of stereodefined alkene derivatives, as well as aromatic and heteroatomic compounds, from 1,2-dihaloalkenes is thus outlined.1 Introduction2 Synthesis of 1,2-Dihaloalkenes3 C–C Bond Forming Reactions4 C–Heteroatom Bond Forming Reactions5 Conclusion

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18

Beletskaya, Irina P. "Transition-metal-catalyzed reactions of carbon-heteroatom bond formation by substitution and addition processes". Pure and Applied Chemistry 77, nr 12 (1.01.2005): 2021–27. http://dx.doi.org/10.1351/pac200577122021.

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Two types of transition-metal-catalyzed cross-coupling reactions, which both lead to the formation of carbon-heteroatom bonds, are considered: RX + E-H and E-X + RM. The potential of addition reactions of E-H or E-E to double or triple bond in C-E bond formation is also demonstrated.

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19

Zhu, Xu, i Shunsuke Chiba. "Copper-catalyzed oxidative carbon–heteroatom bond formation: a recent update". Chemical Society Reviews 45, nr 16 (2016): 4504–23. http://dx.doi.org/10.1039/c5cs00882d.

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This review updates recent advances in Cu-catalyzed (anaerobic) oxidative carbon–heteroatom bond formation on sp³- and sp²-C–H bonds as well as alkenes, classified according to the types of stoichiometric oxidants.

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20

Walter, Sebastian M., Florian Kniep, Eberhardt Herdtweck i Stefan M. Huber. "Halogen-Bond-Induced Activation of a Carbon-Heteroatom Bond". Angewandte Chemie International Edition 50, nr 31 (29.06.2011): 7187–91. http://dx.doi.org/10.1002/anie.201101672.

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21

Haldar, Chabush, Md Emdadul Hoque, Jagriti Chaturvedi, Mirja Md Mahamudul Hassan i Buddhadeb Chattopadhyay. "Ir-catalyzed proximal and distal C–H borylation of arenes". Chemical Communications 57, nr 97 (2021): 13059–74. http://dx.doi.org/10.1039/d1cc05104k.

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Over the past two decades, the C–H bond activation and functionalization reaction has been known as a prevailing method for the construction of carbon–carbon and carbon–heteroatom bonds using various transition metal catalysts.

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22

Kawaguchi, Shin-ichi, Akiya Ogawa, Yuki Sato i Akihiro Nomoto. "Photoinduced Coupling Reaction of Diphenyl(2,4,6-trimethylbenzoyl)phosphine Oxide with Interelement Compounds: Application to the Synthesis of Thio- or Selenophosphinates". Synthesis 49, nr 16 (4.07.2017): 3558–67. http://dx.doi.org/10.1055/s-0036-1588867.

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Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TMDPO) is a radical initiator widely used in the field of macromolecular chemistry, but not often applied in synthetic organic chemistry. We have focused on the use of TMDPO as a phosphorus source in reactions with different E – E compounds, where E – E represents a heteroatom–heteroatom bond, under photoirradiation. Interestingly, the cross-coupling reaction between TMDPO and disulfides or diselenides successfully affords thio- or selenophosphinates and thio- or selenoesters, respectively. The synthesis of series of thio- and selenophosphinates by this photoinduced cross-coupling reaction is demonstrated.

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23

Yamamoto, Yuki, Ryo Tanaka, Shintaro Kodama, Akihiro Nomoto i Akiya Ogawa. "Photoinduced Bisphosphination of Alkynes with Phosphorus Interelement Compounds and Its Application to Double-Bond Isomerization". Molecules 27, nr 4 (14.02.2022): 1284. http://dx.doi.org/10.3390/molecules27041284.

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The addition of interelement compounds with heteroatom-heteroatom single bonds to carbon-carbon unsaturated bonds under light irradiation is believed to be an atomically efficient method to procure materials with carbon-heteroatom bonds. In this study, we achieved the photoinduced bisphosphination of alkynes using the phosphorus interelement compound, tetraphenyldiphosphine monosulfide (1), to stereoselectively obtain the corresponding (E)-vic-1,2-bisphosphinoalkenes, which are important transition-metal ligands. The bisphosphination reaction was performed by mixing 1 and various alkynes and then exposing the mixture to light irradiation. Optimization of the conditions for the bisphosphination reaction resulted in a wide substrate range and excellent trans-selectivity. Moreover, the completely regioselective introduction of pentavalent and trivalent phosphorus groups to the terminal and internal positions of the alkynes, respectively, was achieved. We also found that the novel double-bond isomerization reaction of the synthesized bisphosphinated products occurred with a catalytic amount of a base under mild conditions. Our method for the photoinduced bisphosphination of carbon-carbon unsaturated compounds may have strong implications for both organic synthesis and organometallic and catalyst chemistry.

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24

Paira, Moumita. "Recent Developments of Palladium-Catalyzed C(sp3)/C(sp2)-H Bond Functionalizations Assisted by 8-Aminoquinoline Bidentate Directing Group". Asian Journal of Chemistry 34, nr 8 (2022): 1958–74. http://dx.doi.org/10.14233/ajchem.2022.23774.

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Recently growing demand for cleaner, direct even more regioselective reaction sequences, the formation of carbon-carbon or carbon-heteroatom bonds through C-H activation has developed as a unique methodology. Since the pioneering work of Daugulis on the use of the 8-aminoquinoline auxiliaries as removable bidentate directing groups in palladium-catalyzed C-H bond activations has emerged as a ground breaking strategy for the construction of carbon-carbon or carbon-heteroatom bonds. Hence, this review intends to cover most of the recent advances on 8-aminoquinoline directed palladium-catalyzed C(sp3)/C(sp2)–H bonds functionalizations and highlighted the synthesis of C-branched glycosides.

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25

Glover, Stephen, i Adam Rosser. "Heteroatom Substitution at Amide Nitrogen—Resonance Reduction and HERON Reactions of Anomeric Amides". Molecules 23, nr 11 (31.10.2018): 2834. http://dx.doi.org/10.3390/molecules23112834.

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This review describes how resonance in amides is greatly affected upon substitution at nitrogen by two electronegative atoms. Nitrogen becomes strongly pyramidal and resonance stabilisation, evaluated computationally, can be reduced to as little as 50% that of N,N-dimethylacetamide. However, this occurs without significant twisting about the amide bond, which is borne out both experimentally and theoretically. In certain configurations, reduced resonance and pronounced anomeric effects between heteroatom substituents are instrumental in driving the HERON (Heteroatom Rearrangement On Nitrogen) reaction, in which the more electronegative atom migrates from nitrogen to the carbonyl carbon in concert with heterolysis of the amide bond, to generate acyl derivatives and heteroatom-substituted nitrenes. In other cases the anomeric effect facilitates SN1 and SN2 reactivity at the amide nitrogen.

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26

Baranano, David, Grace Mann i John F. Hartwig. "Nickel and Palladium-Catalyzed Cross-Couplings that Form Carbon-Heteroatom and Carbon-Element Bonds". Current Organic Chemistry 1, nr 3 (wrzesień 1997): 287–305. http://dx.doi.org/10.2174/1385272801666220124194647.

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The transition-metal catalyzed addition of heteroatom nucleophiles to aryl and vinyl halides is reviewed. This chemistry typically involves a nickel- or palladium-based catalyst containing phosphine ligands. In recently developed palladium-catalyzed chemistry, aryl halides react with amines in the presence of base to form arylamines. In similar chemistry catalyzed by both nickel and palladium, aryl and vinyl halides react with alkali metal or tin thiolates or selenides to form aryl and vinyl sulfides, while the reaction of different phosphorus compounds, such as phosphides, phosphonates, and phosphonites, with aryl halides gives compounds with new aryl-p· linkages. In addition to these typically nucleophilic heteroatoms, electrophilic heteroatoms such as boron, silicon, tin, and germanium have also been coupled to aryl electrophiles. The review closes with a brief summary of the general reaction pathways of these C-X bond-forming processes.

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27

Xu, Da-Zhen, Ren-Ming Hu i Yi-Huan Lai. "Iron-Catalyzed Aerobic Oxidative Cross-Dehydrogenative C(sp3)–H/X–H (X = C, N, S) Coupling Reactions". Synlett 31, nr 18 (21.07.2020): 1753–59. http://dx.doi.org/10.1055/s-0040-1707195.

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The direct functionalization of C(sp3)–H bonds is an attractive research topic in organic synthetic chemistry. The cross-dehydrogenative coupling (CDC) reaction provides a simple and powerful tool for the construction of C–C and C–heteroatom bonds. Recently, some progress has been made in the iron-catalyzed aerobic oxidative CDC reactions. Here, we present recent developments in the direct functionalization of C(sp3)–H bonds catalyzed by simple iron salts with molecular oxygen as the terminal oxidant.1 Introduction2 C(sp3)–C Bond Formation3 C(sp3)–N Bond Formation4 C(sp3)–S(Se) Bond Formation5 Conclusion and Outlook

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28

Zeng, Zhongyi, Abigail Feceu, Nardana Sivendran i Lukas J. Gooßen. "Decarboxylation‐Initiated Intermolecular Carbon‐Heteroatom Bond Formation". Advanced Synthesis & Catalysis 363, nr 11 (4.05.2021): 2678–722. http://dx.doi.org/10.1002/adsc.202100211.

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29

Stanger, Amnon. "Strain-Induced Bond Localization. The Heteroatom Case". Journal of the American Chemical Society 120, nr 46 (listopad 1998): 12034–40. http://dx.doi.org/10.1021/ja9819662.

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30

Corma, A., A. Leyva-Pérez i Maria J. Sabater. "Gold-Catalyzed Carbon−Heteroatom Bond-Forming Reactions". Chemical Reviews 111, nr 3 (9.03.2011): 1657–712. http://dx.doi.org/10.1021/cr100414u.

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31

Cavedon, Cristian, Peter H. Seeberger i Bartholomäus Pieber. "Photochemical Strategies for Carbon-Heteroatom Bond Formation". European Journal of Organic Chemistry 2020, nr 10 (16.09.2019): 1379–92. http://dx.doi.org/10.1002/ejoc.201901173.

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32

Choury, Mickael, Alexandra Basilio Lopes, Gaëlle Blond i Mihaela Gulea. "Synthesis of Medium-Sized Heterocycles by Transition-Metal-Catalyzed Intramolecular Cyclization". Molecules 25, nr 14 (9.07.2020): 3147. http://dx.doi.org/10.3390/molecules25143147.

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Medium-sized heterocycles (with 8 to 11 atoms) constitute important structural components of several biologically active natural compounds and represent promising scaffolds in medicinal chemistry. However, they are under-represented in the screening of chemical libraries as a consequence of being difficult to access. In particular, methods involving intramolecular bond formation are challenging due to unfavorable enthalpic and entropic factors, such as transannular interactions and conformational constraints. The present review focuses on the synthesis of medium-sized heterocycles by transition-metal-catalyzed intramolecular cyclization, which despite its drawbacks remains a straightforward and attractive synthesis strategy. The obtained heterocycles differ in their nature, number of heteroatoms, and ring size. The methods are classified according to the metal used (palladium, copper, gold, silver), then subdivided according to the type of bond formed, namely carbon–carbon or carbon–heteroatom.

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Shao, Ailong, Meng Gao, Songtao Chen, Tao Wang i Aiwen Lei. "CO/O2 assisted oxidative carbon–carbon and carbon–heteroatom bond cleavage for the synthesis of oxosulfonates from DMSO and olefins". Chemical Science 8, nr 3 (2017): 2175–78. http://dx.doi.org/10.1039/c6sc04480h.

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Dénès, Fabrice. "Intermolecular Radical C–H Bond Activation: A Powerful Tool for Late Stage Functionalization". CHIMIA International Journal for Chemistry 74, nr 1 (26.02.2020): 23–32. http://dx.doi.org/10.2533/chimia.2020.23.

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The synthesis of complex molecules via radical reactions involving carbon–carbon and carbon–heteroatom bonds has become a very successful approach. Radical chemistry has long been dominated by the use of tin-based reagents. Those strongly contributed to the development of the field, allowing one to achieve spectacular transformations, most of which being difficult or impossible to achieve under ionic conditions, and giving access to invaluable kinetics data that paved the way for the development of improved protocols and the design of new synthetic strategies. However, tin reagents and tin byproducts are often toxic and they proved to make purification steps sometimes tedious. In this context, tin-free methods have progressively gained in interest. This short review aims at providing the reader with alternative methods employing C–H bonds in place of the classical alkyl halides to generate, via an intermolecular hydrogen atom transfer (HAT), the radical species. Examples of carbon–carbon and carbon–heteroatom bond formation using this type of C–H bond activation approach will be provided, from early reports to the more recent developments.

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Jiang, Chao, Xiangbing Qi i Chao Yang. "Alkylzirconocenes in Organic Synthesis: An Overview". Synthesis 53, nr 06 (11.02.2021): 1061–76. http://dx.doi.org/10.1055/s-0040-1706146.

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AbstractOrganozirconium chemistry has found extensive applications in organic synthesis since its discovery in the last century. Alkylzirconocenes, which are easily generated by the hydrozirconation of alkenes with the Schwartz reagent, are widely utilized for carbon–carbon and carbon–heteroatom bond formation. This short review summarizes the progress to date on the applications alkylzirconocenes in organic synthesis.1 Introduction2 General Methods for Generating Alkylzirconocenes3 Transformations of Alkylzirconocenes by Heteroatoms4 Insertion of Unsaturated Groups into Alkylzirconocenes5 Transmetalations6 Cross-Coupling Reactions of Alkylzirconocenes7 Photochemistry of Alkylzirconocenes8 Bimetallic Reagents of Zirconium9 Asymmetric Transformations10 Applications of Alkylzirconocenes Generated from the Negishi Reagent11 Conclusions and Outlook

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Deb, Mayukh, Jatinder Singh, Shuvadip Mallik, Susanta Hazra i Anil J. Elias. "Borylation, silylation and selenation of C–H bonds in metal sandwich compounds by applying a directing group strategy". New Journal of Chemistry 41, nr 23 (2017): 14528–38. http://dx.doi.org/10.1039/c7nj02388j.

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Zhou, Rong, Rongfang Liu, Kai Zhang, Ling Han, Honghui Zhang, Wenchao Gao i Ruifeng Li. "Metal-free formal carbon–halogen bond insertion: facile syntheses of 3-halo 3,3′-disubstituted oxindoles and spirooxindole-γ-butyrolactones". Chemical Communications 53, nr 51 (2017): 6860–63. http://dx.doi.org/10.1039/c7cc03765a.

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Kamanna, Kantharaju, i Santosh Y. Khatavi. "Microwave-accelerated Carbon-carbon and Carbon-heteroatom Bond Formation via Multi-component Reactions: A Brief Overview". Current Microwave Chemistry 7, nr 1 (23.06.2020): 23–39. http://dx.doi.org/10.2174/2213346107666200218124147.

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Multi-Component Reactions (MCRs) have emerged as an excellent tool in organic chemistry for the synthesis of various bioactive molecules. Among these, one-pot MCRs are included, in which organic reactants react with domino in a single-step process. This has become an alternative platform for the organic chemists, because of their simple operation, less purification methods, no side product and faster reaction time. One of the important applications of the MCRs can be drawn in carbon- carbon (C-C) and carbon-heteroatom (C-X; X = N, O, S) bond formation, which is extensively used by the organic chemists to generate bioactive or useful material synthesis. Some of the key carbon- carbon bond forming reactions are Grignard, Wittig, Enolate alkylation, Aldol, Claisen condensation, Michael and more organic reactions. Alternatively, carbon-heteroatoms containing C-N, C-O, and C-S bond are also found more important and present in various heterocyclic compounds, which are of biological, pharmaceutical, and material interest. Thus, there is a clear scope for the discovery and development of cleaner reaction, faster reaction rate, atom economy and efficient one-pot synthesis for sustainable production of diverse and structurally complex organic molecules. Reactions that required hours to run completely in a conventional method can now be carried out within minutes. Thus, the application of microwave (MW) radiation in organic synthesis has become more promising considerable amount in resource-friendly and eco-friendly processes. The technique of microwaveassisted organic synthesis (MAOS) has successfully been employed in various material syntheses, such as transition metal-catalyzed cross-coupling, dipolar cycloaddition reaction, biomolecule synthesis, polymer formation, and the nanoparticle synthesis. The application of the microwave-technique in carbon-carbon and carbon-heteroatom bond formations via MCRs with major reported literature examples are discussed in this review.

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Murai, Masahito, Kengo Nishimura i Kazuhiko Takai. "Palladium-catalyzed double-bond migration of unsaturated hydrocarbons accelerated by tantalum chloride". Chemical Communications 55, nr 19 (2019): 2769–72. http://dx.doi.org/10.1039/c9cc00223e.

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Li, Man, Junting Hong, Wei Xiao, Yang Yang, Di Qiu i Fanyang Mo. "Electrocatalytic Oxidative Transformation of Organic Acids for Carbon–Heteroatom and Sulfur–Heteroatom Bond Formation". ChemSusChem 13, nr 7 (21.02.2020): 1661–87. http://dx.doi.org/10.1002/cssc.201902657.

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Yu, Bo, i Jóhannes Reynisson. "Bond stability of the “undesirable” heteroatom–heteroatom molecular moieties for high-throughput screening libraries". European Journal of Medicinal Chemistry 46, nr 12 (grudzień 2011): 5833–37. http://dx.doi.org/10.1016/j.ejmech.2011.09.044.

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Yan, Guobing, Vinod K. Tiwari, Jie Yu, Anoop S. Singh i Jian Yu. "Recent Developments on Denitrogenative Functionalization of Benzotriazoles". Synthesis 52, nr 24 (1.09.2020): 3781–800. http://dx.doi.org/10.1055/s-0040-1707253.

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AbstractBenzotriazoles are employed as useful synthons in organic synthesis, and due to their unique structural motif, they are able to undergo denitrogenation during the construction of new bonds. Various methods for the functionalization of benzotriazoles as precursors of ortho-amino arenediazoniums have recently been developed that involve transition-metal-catalyzed coupling reactions, mainly via cyclization, borylation, alkenylation, alkylation, carbonylation and the formation of carbon–heteroatom bonds. In this short review, we primarily focus on the recent applications of benzotriazoles in organic chemistry that proceed via a denitrogenative process, and the mechanisms are also discussed.1 Introduction2 Common Synthetic Routes Allowing Easy Access to Benzotriazole Derivatives3 Formation of C–C Bonds3.1 Cyclization Reactions3.2 Arylation, Alkenylation, Alkylation and Carbonylation Reactions4 Carbon–Heteroatom Bond Formation5 Miscellaneous Denitrogenative Functionalization6 Conclusions and Future Perspectives

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Yorimitsu, Hideki. "Homolytic substitution at phosphorus for C–P bond formation in organic synthesis". Beilstein Journal of Organic Chemistry 9 (28.06.2013): 1269–77. http://dx.doi.org/10.3762/bjoc.9.143.

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Organophosphorus compounds are important in organic chemistry. This review article covers emerging, powerful synthetic approaches to organophosphorus compounds by homolytic substitution at phosphorus with a carbon-centered radical. Phosphination reagents include diphosphines, chalcogenophosphines and stannylphosphines, which bear a weak P–heteroatom bond for homolysis. This article deals with two transformations, radical phosphination by addition across unsaturated C–C bonds and substitution of organic halides.

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Hartwig, John F. "Carbon–heteroatom bond formation catalysed by organometallic complexes". Nature 455, nr 7211 (wrzesień 2008): 314–22. http://dx.doi.org/10.1038/nature07369.

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KUWABARA, Junpei, i Takaki KANBARA. "Polycondensation via Complex-Catalyzed Carbon-Heteroatom Bond Formation". KOBUNSHI RONBUNSHU 68, nr 5 (2011): 281–88. http://dx.doi.org/10.1295/koron.68.281.

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Takemoto, Yoshiji, i Hideto Miyabe. "ChemInform Abstract: Asymmetric Carbon-Heteroatom Bond-Forming Reactions". ChemInform 42, nr 18 (7.04.2011): no. http://dx.doi.org/10.1002/chin.201118241.

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Liu, Wen-Bo, Muhammad Usman i Xiao-Wen Zhang. "Silicon-Tethered Frameworks as Directing Groups for Carbon–Carbon and Carbon–Heteroatom Bond Formation". Synthesis 51, nr 07 (5.03.2019): 1529–44. http://dx.doi.org/10.1055/s-0037-1612123.

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Recent advances in the use of silicon-tethered frameworks as directing groups for the efficient construction of C–C, C–B, C–O and C–X (X = halogen) bonds are discussed in this short review. In addition, mechanistic insights are briefly discussed. Hence, the goal of this short review is to give an overview of the state of the art in this field, encompassing the reactivity, selectivity and efficiency of different processes.1 Introduction2 Carbon–Carbon Bond Formation2.1 Alkenylation2.2 Arylation2.3 Carbonylation3 Carbon–Boron Bond Formation4 Carbon–Oxygen and Carbon–Halogen Bond Formation5 Conclusion

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Zhao, Jian-Nan, Muzaffar Kayumov, Dong-Yu Wang i Ao Zhang. "Transition-Metal-Free Aryl–Heteroatom Bond Formation via C–S Bond Cleavage". Organic Letters 21, nr 18 (29.08.2019): 7303–6. http://dx.doi.org/10.1021/acs.orglett.9b02584.

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Samanta, Rajarshi, Kiran Matcha i Andrey P. Antonchick. "Metal-Free Oxidative Carbon-Heteroatom Bond Formation Through C-H Bond Functionalization". European Journal of Organic Chemistry 2013, nr 26 (17.06.2013): 5769–804. http://dx.doi.org/10.1002/ejoc.201300286.

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Iranpoor, Nasser, Habib Firouzabadi, Elham Etemadi-Davan, Arash Nematollahi i Hamid Reza Firouzi. "A novel nickel-catalyzed synthesis of thioesters, esters and amides from aryl iodides in the presence of chromium hexacarbonyl". New Journal of Chemistry 39, nr 8 (2015): 6445–52. http://dx.doi.org/10.1039/c5nj00655d.

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