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Search for "adduct" in Full Text gives 582 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Using the phospha-Michael reaction for making phosphonium phenolate zwitterions

  • Matthias R. Steiner,
  • Max Schmallegger,
  • Larissa Donner,
  • Johann A. Hlina,
  • Christoph Marschner,
  • Judith Baumgartner and
  • Christian Slugovc

Beilstein J. Org. Chem. 2024, 20, 41–51, doi:10.3762/bjoc.20.6

Graphical Abstract
  • product of interest 2a. Compound 2a was identified by a combination of NMR spectroscopic methods and single-crystal X-ray structure analysis (vide infra) as the zwitterionic phospha-Michael adduct of 1 and acrylonitrile, formally stabilized by proton transfer from the phenol group to the initially formed
  • position 3 (4JHH ≈ 2.5 Hz) as well as coupling with the phosphonium center (3JPH ≈ 14 Hz). In comparison to phosphine 1, in which the same proton displays a resonance at 6.88 ppm (4JHH = 2.5 Hz, 3JPH = 5.8 Hz [35]), this signal is characteristically up-field shifted in every adduct 2a–j (Table 1). The
  • = 3.9 Hz) [30]. Compared to the parent phosphine 1 (155.9 ppm, 2JPC = 19.3 Hz) [35] a pronounced down-field shift occurred upon adduct formation, which suggests a considerable contribution of a quinonic resonance structure as benzoquinones exhibit 13C NMR shifts of about 188 ppm and hydroquinones of
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Published 10 Jan 2024

1-Butyl-3-methylimidazolium tetrafluoroborate as suitable solvent for BF3: the case of alkyne hydration. Chemistry vs electrochemistry

  • Marta David,
  • Elisa Galli,
  • Richard C. D. Brown,
  • Marta Feroci,
  • Fabrizio Vetica and
  • Martina Bortolami

Beilstein J. Org. Chem. 2023, 19, 1966–1981, doi:10.3762/bjoc.19.147

Graphical Abstract
  • carried out in an undivided cell (see Supporting Information File 1, Figure S1d). In this last case, in fact, the NHC-BF3 adduct is formed between anodically electrogenerated BF3 and cathodically electrogenerated NHC [103]. Evaluation of the current efficiency in the electrogeneration of BF3 in BMIm-BF4
  • base and the base–BF3 adduct, we should obtain an approximate current yield. Our first choice was N,N-diisopropylethylamine (DIPEA), as the DIPEA-BF3 adduct is reported in the literature and fully characterized by NMR in CDCl3 [113]. To be consistent with literature data, the BF4− peak in neat BMIm-BF4
  • adduct in CDCl3 (53.8, 41.6, 19.5, 18.9, 9.9), inducing us to think to have the DIPEA-BF3 adduct in the solution. To confirm this assumption, we prepared a DIPEA solution in BMIm-BF4 to record the 13C NMR spectrum, but unfortunately DIPEA is not soluble enough in BMIm-BF4 to obtain a decent spectrum
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Published 28 Dec 2023

Controlling the reactivity of La@C82 by reduction: reaction of the La@C82 anion with alkyl halide with high regioselectivity

  • Yutaka Maeda,
  • Saeka Akita,
  • Mitsuaki Suzuki,
  • Michio Yamada,
  • Takeshi Akasaka,
  • Kaoru Kobayashi and
  • Shigeru Nagase

Beilstein J. Org. Chem. 2023, 19, 1858–1866, doi:10.3762/bjoc.19.138

Graphical Abstract
  • analysis of the single-bonded adduct 3a revealed the addition site of the p-methoxybenzyl group on La@C2v-C82. Theoretical calculations indicated that the addition site carbons in neutral La@C2v-C82 have high spin density, whereas those in the La@C2v-C82 anion do not have high charge densities. Thus, the
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Published 11 Dec 2023

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

Graphical Abstract
  • polar solvent, i.e., methanol, to its solution. The main requirement for the polar solvent is that it should not dissolve the catalyst while it should completely dissolve the product. Therefore, we investigated the solubility of the Michael adduct 14 in methanol, ethanol, propan-2-ol, Patosolv® (a
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Published 24 Nov 2023

Active-metal template clipping synthesis of novel [2]rotaxanes

  • Cătălin C. Anghel,
  • Teodor A. Cucuiet,
  • Niculina D. Hădade and
  • Ion Grosu

Beilstein J. Org. Chem. 2023, 19, 1776–1784, doi:10.3762/bjoc.19.130

Graphical Abstract
  • = 2280.2642 corresponding to the [R1 + Na]+ adduct and at m/z = 2320.2021 assigned to the [R1+Cu]+ ion (Figure 1, top, left and Figure S17 in Supporting Information File 1), while the HRESI(+)-MS of R2 displayed the base peak at m/z = 2233.2883 corresponding to the protonated molecular ion. Formation of the
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Published 20 Nov 2023

Selectivity control towards CO versus H2 for photo-driven CO2 reduction with a novel Co(II) catalyst

  • Lisa-Lou Gracia,
  • Philip Henkel,
  • Olaf Fuhr and
  • Claudia Bizzarri

Beilstein J. Org. Chem. 2023, 19, 1766–1775, doi:10.3762/bjoc.19.129

Graphical Abstract
  • ) intermediate could be favored concerning the formation of the CO2 adduct with the reduced metal center. Thus, besides the development of novel efficient catalysts, different strategies have been pursued to switch the catalyst selectivity towards carbon products [4][5]. Generally, scientists can interplay by
  • catalytic current was observed at the onset potential of −1.4 V. Although a direct comparison between Co(II) and Fe(II) ions cannot be made, it is reasonable to suggest that after the first reduction a −NCS ligand detaches and an adduct with CO2 is formed, as it was calculated for a similar thiocyanate
  • also serve as a reductant [47]. The reduced species PS− can be oxidized back to PS by a molecule of 1, which could detach a −NCS anion and offer a vacant site to coordinate a proton (then following an H2 evolution path) or a molecule of CO2 [46]. The adduct with CO2 is further reduced (by PS− or BI
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Published 17 Nov 2023

Unprecedented synthesis of a 14-membered hexaazamacrocycle

  • Anastasia A. Fesenko and
  • Anatoly D. Shutalev

Beilstein J. Org. Chem. 2023, 19, 1728–1740, doi:10.3762/bjoc.19.126

Graphical Abstract
  • the most electrophilic C2 carbon of the pyrimidine ring in 8 to give intermediate A. Cleavage of the C2–N3 bond in the latter followed by proton transfer in the formed zwitterion B affords bis-amidrazone C. Next, two molecules of bis-amidrazone C react with each other forming adduct D, which either
  • geometry of this structure favors the formation of adduct D and then macrocycle 5. All these data explain the formation of macrocycle 5 from pyrazolopyrimidine 8 in acceptable yields (see Table 1), despite the multistep transformation (Scheme 6), rather harsh reaction conditions (>1.5 equivalents of N2H4
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Published 15 Nov 2023

Sulfur-containing spiroketals from Breynia disticha and evaluations of their anti-inflammatory effect

  • Ken-ichi Nakashima,
  • Naohito Abe,
  • Masayoshi Oyama,
  • Hiroko Murata and
  • Makoto Inoue

Beilstein J. Org. Chem. 2023, 19, 1604–1614, doi:10.3762/bjoc.19.117

Graphical Abstract
  • the ethyl acetate fraction (Figure 1). The structures of known compounds 5–7 were identified based on 1H and 13C NMR data [2][3][10]. Breynin J (1) was isolated as an amorphous, colorless powder. The HRESIMS spectrum exhibited a sodium adduct ion peak at m/z 1107.3177, consistent with a molecular
  • isolated as an amorphous, colorless powder. Because the sodium adduct ion peak at m/z 1107.3178 in the HRESIMS spectrum gave the same molecular formula as that of 1 (C45H64O28SNa, calcd 1107.3197), compounds 1 and 2 were determined to be isomers. The 1D and 2D NMR spectroscopic data indicated that the
  • compounds 2 and 7 were determined to be 1S,3R,4R,6S,7R,9S,11S,12R,16S,17S (Figure 3c). Probreynogenin (3) was isolated as an amorphous, colorless solid. The molecular formula of 3 was determined to be C23H27NO11S based on the sodium adduct ion peak at m/z 548.1197 [M + Na]+ (calcd 548.1197) observed by
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Published 19 Oct 2023

Morpholine-mediated defluorinative cycloaddition of gem-difluoroalkenes and organic azides

  • Tzu-Yu Huang,
  • Mario Djugovski,
  • Sweta Adhikari,
  • Destinee L. Manning and
  • Sudeshna Roy

Beilstein J. Org. Chem. 2023, 19, 1545–1554, doi:10.3762/bjoc.19.111

Graphical Abstract
  • their 3JH−F coupling constants in the 1H NMR spectra, circa 32.0 Hz for Z-isomers and 8.0 Hz for E-isomers [33]. A peak was observed at −158.2 ppm in the 19F NMR spectrum after 2 h of the reaction, which could be the fluoride salt of the dimorpholine adduct. This peak was also found when the reaction
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Published 05 Oct 2023

Synthesis and biological evaluation of Argemone mexicana-inspired antimicrobials

  • Jessica Villegas,
  • Bryce C. Ball,
  • Katelyn M. Shouse,
  • Caleb W. VanArragon,
  • Ashley N. Wasserman,
  • Hannah E. Bhakta,
  • Allen G. Oliver,
  • Danielle A. Orozco-Nunnelly and
  • Jeffrey M. Pruet

Beilstein J. Org. Chem. 2023, 19, 1511–1524, doi:10.3762/bjoc.19.108

Graphical Abstract
  • effects of each modification. It was found that the acetone adduct B9 and the partially reduced variant B10 were more potent, while the fully reduced variant B11 was significantly less active (Table 2). These results suggested the activity of B1 could be similarly altered by the same modifications to the
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Published 29 Sep 2023

α-(Aminomethyl)acrylates as acceptors in radical–polar crossover 1,4-additions of dialkylzincs: insights into enolate formation and trapping

  • Angel Palillero-Cisneros,
  • Paola G. Gordillo-Guerra,
  • Fernando García-Alvarez,
  • Olivier Jackowski,
  • Franck Ferreira,
  • Fabrice Chemla,
  • Joel L. Terán and
  • Alejandro Perez-Luna

Beilstein J. Org. Chem. 2023, 19, 1443–1451, doi:10.3762/bjoc.19.103

Graphical Abstract
  • protodemetalation to provide ultimately the 1,4-addition adduct. In the presence of carbonyl acceptors, aldol condensation occurs providing overall a tandem 1,4-addition–aldol process. When a tert-butanesulfinyl moiety is present on the nitrogen atom, these electrophilic substitution reactions occur with good
  • )acrylates in hands, we carried out an initial survey of their reaction with Et2Zn in CH2Cl2 at −33 °C on addition of air. In these conditions, acrylate 10 led to the recovery (following aqueous work-up) of sulfinamide 9 without traces of formation of the 1,4-adduct (Scheme 4). By contrast, 1,4-addition
  • without subsequent fragmentation was observed starting from α-(aminomethyl)acrylates having free N–H bonds (Table 2). The reaction of Et2Zn with acrylates 5–7 afforded the desired 1,4-addition products 11–13 in 42–55% yield. Better results were obtained starting from 8a, which delivered adduct 14a in 79
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Published 21 Sep 2023

Metal catalyst-free N-allylation/alkylation of imidazole and benzimidazole with Morita–Baylis–Hillman (MBH) alcohols and acetates

  • Olfa Mhasni,
  • Jalloul Bouajila and
  • Farhat Rezgui

Beilstein J. Org. Chem. 2023, 19, 1251–1258, doi:10.3762/bjoc.19.93

Graphical Abstract
  • , the use of DABCO, commonly used as a powerful catalyst or a nucleophilic additive in the reaction of acyclic MBH adducts with various nucleophiles [21][34][35][36][37], did not afford the SN2/SN2’ products but provided the 1,4-adduct 8a in 84% yield (Table 2, entry 4). Alternatively, we also
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Published 01 Sep 2023

Selective construction of dispiro[indoline-3,2'-quinoline-3',3''-indoline] and dispiro[indoline-3,2'-pyrrole-3',3''-indoline] via three-component reaction

  • Ziying Xiao,
  • Fengshun Xu,
  • Jing Sun and
  • Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 1234–1242, doi:10.3762/bjoc.19.91

Graphical Abstract
  • as Michael acceptors, 1,3-dipolarophiles, 1,4-dienophiles and other multiple substrates. They have been widely employed as key component to finish many multicomponent and domino reactions [26][27][28][29][30][31][32][33][34][35]. Recently, the Michael adduct of 3-methyleneoxindoles with various
  • nucleophiles, especially active methylene compounds, have attracted much attentions [36][37][38][39][40][41]. This kind of Michael adduct has more than one reactive site and could proceed domino reactions with various electrophiles [42][43][44][45][46][47][48][49]. In this respect, several elegant domino or
  • spirooxindoles, in which the in situ-generated Michael adduct of 3-ethoxycarbonylmethyleneoxindole underwent a Mannich reaction and annulation reaction with in situ-generated aldimines (reaction 1 in Scheme 1) [50][51]. Tanaka reported chiral quinidine derivative-catalyzed Michael–Henry cascade reactions of
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Published 22 Aug 2023

Exploring the role of halogen bonding in iodonium ylides: insights into unexpected reactivity and reaction control

  • Carlee A. Montgomery and
  • Graham K. Murphy

Beilstein J. Org. Chem. 2023, 19, 1171–1190, doi:10.3762/bjoc.19.86

Graphical Abstract
  • , they believed that the reaction was likely initiated by either single electron transfer between the reagents (not shown), or by electrophilic addition of the olefin onto the ylide, forming intermediate adduct 17. This was followed by formation of iodocycle 18, from which reductive elimination of
  • direct cycloaddition between the ylide and alkene. Murphy’s report of formal X–H insertions with iodonium ylides was similarly proposed to initiate upon complex formation with a Lewis base. Adduct formation was believed to both increase the acidity of halogen bond acceptor’s attached protons, as well as
  • -derived iodonium ylide (60/I-13) (Figure 12, inset), which showed a 5.1 kcal/mol energy difference between rapidly equilibrating halogen-bonded fluoride adducts. The lower energy adduct IntA had fluoride residing in the stronger σ-hole opposite the β-dicarbonyl (syn to the arene), whereas the higher
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Published 07 Aug 2023

Two new lanostanoid glycosides isolated from a Kenyan polypore Fomitopsis carnea

  • Winnie Chemutai Sum,
  • Sherif S. Ebada,
  • Didsanutda Gonkhom,
  • Cony Decock,
  • Rémy Bertrand Teponno,
  • Josphat Clement Matasyoh and
  • Marc Stadler

Beilstein J. Org. Chem. 2023, 19, 1161–1169, doi:10.3762/bjoc.19.84

Graphical Abstract
  • ]. Results Structure elucidation Compound 1 was isolated as an off-white solid powder. Its molecular formula was determined to be C43H68O12 based on HRESIMS results that revealed a sodium adduct ion peak at m/z 799.4604 ([M + Na]+ calcd for C43H68O12Na+, 799.4603) indicating the presence of ten degrees of
  • trivially named as forpinioside B. Compound 2 was obtained as a colourless oil and its molecular formula was determined to be C43H68O13 according to its HRESIMS spectrum that revealed a sodium adduct ion peak at m/z 815.4550 ([M + Na]+ calcd for C43H68O13Na+, 815.4552) indicating the presence of an
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Published 02 Aug 2023

Photoredox catalysis harvesting multiple photon or electrochemical energies

  • Mattia Lepori,
  • Simon Schmid and
  • Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

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Published 28 Jul 2023

The unique reactivity of 5,6-unsubstituted 1,4-dihydropyridine in the Huisgen 1,4-diploar cycloaddition and formal [2 + 2] cycloaddition

  • Xiu-Yu Chen,
  • Hui Zheng,
  • Ying Han,
  • Jing Sun and
  • Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 982–990, doi:10.3762/bjoc.19.73

Graphical Abstract
  • gives the well-known Huisgen 1,4-dipole A. Secondly, Michael addition of the 1,4-dipole A to 5,6-unsubstituted 1,4-dihydropyridine gives the adduct intermediate B. At last, the intramolecular coupling of the negative and the positive charges in intermediate B directly affords isoquinolino[1,2-f][1,6
  • acetylenedicarboxylate to give the adduct C. Then, the direct coupling of the positive charge and the negative charge affords the 2-azabicyclo[4.2.0]octa-3,7-diene 5. On the other hand, a carbenium ion D can be formed by migration of a hydrogen atom in intermediate C, which in turn converts into a fused bicyclic
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Published 29 Jun 2023

First synthesis of acylated nitrocyclopropanes

  • Kento Iwai,
  • Rikiya Kamidate,
  • Khimiya Wada,
  • Haruyasu Asahara and
  • Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2023, 19, 892–900, doi:10.3762/bjoc.19.67

Graphical Abstract
  • ) halogenation, and 3) ring closure (Scheme 2). β-Nitrostyrene 2 serves as an appropriate acceptor for conjugate addition by diethyl malonate (3a) to afford adduct 4a, in which the methine group flanked by two carbonyl groups is readily halogenated, and the subsequent intramolecular nucleophilic substitution by
  • substrates, almost equal amounts of diastereomers were formed. Whereas 4b was isolated by recrystallization of the reaction mixture from ethanol, the other adducts 4c–g were easily isolated by column chromatography. For comparison with previously reported results, adduct 4b, derived from acetylacetone (3b
  • ), was subjected to cyclopropanation according to a method described in the literature [13]. To a solution of adduct 4b in toluene, (diacetoxyiodo)benzene and tetrabutylammonium iodide were added, and the resulting mixture was stirred at room temperature for 14 h. Unexpectedly, from the reaction mixture
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Published 21 Jun 2023

Pyridine C(sp2)–H bond functionalization under transition-metal and rare earth metal catalysis

  • Haritha Sindhe,
  • Malladi Mounika Reddy,
  • Karthikeyan Rajkumar,
  • Akshay Kamble,
  • Amardeep Singh,
  • Anand Kumar and
  • Satyasheel Sharma

Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62

Graphical Abstract
  • regioselectively at the C4 position of the organoborate intermediate 60 delivering the σH-adduct intermediates 62 and 63. Subsequently, hydride elimination with the help of the organoborane gave the desired alkylated product 59 and regenerates the hydride catalyst. Further enantioselective pyridine C–H alkylation
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Published 12 Jun 2023

Photocatalytic sequential C–H functionalization expediting acetoxymalonylation of imidazo heterocycles

  • Deepak Singh,
  • Shyamal Pramanik and
  • Soumitra Maity

Beilstein J. Org. Chem. 2023, 19, 666–673, doi:10.3762/bjoc.19.48

Graphical Abstract
  • (Scheme 3A). Upon analyzing the reaction mixture of 1a and 2a under standard conditions in the presence of TEMPO, we found only a trace of the desired product 4a. At the same time, a TEMPO-DEM adduct 7 and TEMPO-OAc adduct 8 were identified by the HRMS analysis of the crude reaction mixture, indicating
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Published 12 May 2023

Cassane diterpenoids with α-glucosidase inhibitory activity from the fruits of Pterolobium macropterum

  • Sarot Cheenpracha,
  • Ratchanaporn Chokchaisiri,
  • Lucksagoon Ganranoo,
  • Sareeya Bureekaew,
  • Thunwadee Limtharakul and
  • Surat Laphookhieo

Beilstein J. Org. Chem. 2023, 19, 658–665, doi:10.3762/bjoc.19.47

Graphical Abstract
  • a Diels–Alder adduct, thus displaying the same relative configuration found in pterolobirin B [11]. The absolute configuration of 3 was thus elucidated as 5S,6R,8R,9S,10R,15R,5′S,6′R,8′R,9′S,10′R,12′S,13′R,14′R,15′S,16′S and the measured ECD spectrum (Figure 4b) with the positive at 243 nm and
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Published 11 May 2023

Enolates ambushed – asymmetric tandem conjugate addition and subsequent enolate trapping with conventional and less traditional electrophiles

  • Péter Kisszékelyi and
  • Radovan Šebesta

Beilstein J. Org. Chem. 2023, 19, 593–634, doi:10.3762/bjoc.19.44

Graphical Abstract
  • reaction with the α-aminoether 118. This reagent released an iminium ion into the reaction medium that reacted with the Al enolate 117 [66]. Furthermore, the Mannich adduct was then reacted with Grignard reagents that replaced the dimethylamino group (Scheme 30). Alexakis and co-workers also investigated
  • acryloyloxazolidinone 183, the reaction gave the expected aldol product 184 in good yields and diastereomeric ratios with a preference toward the syn-adduct (Scheme 47A). Interestingly, when they used methacryloyloxazolidinone 185 as a Michael acceptor, the X-ray analysis of the product showed a rearranged structure
  • silylation/aldol cyclization sequence where the diastereoselectivity of the reaction is determined by the Si nucleophile used [90]. Using Me2PhSiZnX·2LiX in combination with ligand L21 leads to the trans adduct, while Me2PhSiBpin together with L30 provides the cis product. Consequently, the authors have
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Published 04 May 2023

Transition-metal-catalyzed domino reactions of strained bicyclic alkenes

  • Austin Pounder,
  • Eric Neufeld,
  • Peter Myler and
  • William Tam

Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38

Graphical Abstract
  • undergoing reductive elimination to afford to [2 + 2] adduct, β-oxygen elimination followed by E/Z isomerization and intramolecular lactonization generates the annulated coumarin scaffold. In 2003, the Cheng lab extended on this Ni-catalyzed ring-opening strategy [31]. It was noted the addition of 1.5
  • final ring-opened adduct 37. Copper-catalyzed reactions In 2009, Pineschi and co-workers explored the Cu-catalyzed rearrangement/allylic alkylation of 2,3-diazabicyclo[2.2.1]heptenes 47 with Grignard reagents 48 (Scheme 8) [41]. The reaction is thought to proceed via the Lewis acid-catalyzed [3,4
  • derivatives 85. The reaction was amenable for both electron-rich and deficient indoles. When the reaction was attempted on electron-deficient oxabicyclic alkene derivatives, it was observed the reaction did not undergo dehydration to give the 2-naphthyl product, rather the ring-opened 1,2-hydroxy adduct. When
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Published 24 Apr 2023

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

Graphical Abstract
  • of adduct J. The product 26 is released via a reductive elimination step, generating at the same time the reduced cobalt Cp*Co(I), which is converted to the active catalyst after oxidation. The same year, Yoshino and Matsunaga described a similar methodology, using the cobalt(III) complex [Cp*Co
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Published 17 Apr 2023

Mechanochemical solid state synthesis of copper(I)/NHC complexes with K3PO4

  • Ina Remy-Speckmann,
  • Birte M. Zimmermann,
  • Mahadeb Gorai,
  • Martin Lerch and
  • Johannes F. Teichert

Beilstein J. Org. Chem. 2023, 19, 440–447, doi:10.3762/bjoc.19.34

Graphical Abstract
  • such as n-BuLi or NaOt-Bu (in various equivalents, Table 1, entries 1 and 2) or weak bases (Et3N, K2CO3 or K3PO4, Table 1, entries 3–5) either did give no conversion to 5 at all or delivered a catalytically inactive complex, which we assign to a CO2 adduct of 5 (Table 1, entry 4) [51][52]. We
  • hypothesize that in this CO2 adduct, the guanidine moiety is unavailable to perform its assisting part in catalysis through hydrogen-bonding interaction [48]. As additional evidence to support the formation of the CO2 adduct of 5, we can show that bubbling of CO2 through a solution of 5 leads to catalytically
  • inactive complexes (see Supporting Information File 1 for details). This also supports the notion that during catalytic ester hydrogenation, the guanidinium moiety acts as a hydrogen bond donor to the esters [48]. The formation of a CO2 adduct hinders the ability to form hydrogen bonds. Furthermore
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Published 14 Apr 2023
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