Mechanochemical halogenation of unsymmetrically substituted azobenzenes

• Dajana Barišić,
• Mario Pajić,
• Ivan Halasz,
• Darko Babić and
• Manda Ćurić

Beilstein J. Org. Chem. 2022, 18, 680–687, doi:10.3762/bjoc.18.69

• protocol for the ortho-halogenation of acetanilide with NXS (X = Cl, Br, I) using Pd(OAc)2 as precatalyst in the presence of p-toluenesulfonic acid (TsOH) as an additive under solvent-free conditions [49]. Recently, Mal and Bera reported the utilization of NXS (X = Br, Cl) as bifunctional reagents for the

Development of N-F fluorinating agents and their fluorinations: Historical perspective

• Teruo Umemoto,
• Yuhao Yang and
• Gerald B. Hammond

Beilstein J. Org. Chem. 2021, 17, 1752–1813, doi:10.3762/bjoc.17.123

• high yields. Although aromatics such as anisole, toluene, and acetanilide could also be fluorinated by NFSI, these reactions required neat conditions and high temperatures, indicating that NFSI was not so powerful. 1-15. N-Fluorosaccharin and N-fluorophthalimide In 1991, Gakh et al. reported the

When metal-catalyzed C–H functionalization meets visible-light photocatalysis

• Lucas Guillemard and
• Joanna Wencel-Delord

Beilstein J. Org. Chem. 2020, 16, 1754–1804, doi:10.3762/bjoc.16.147

• system merging C–H activation and photoredox catalysis was also applied to C(sp2)–H acylation reactions via the generation of acyl radicals. In 2015, Li, Wang and co-workers reported the ortho-acylation of acetanilide derivatives using α-ketoacids as coupling partners and employing synergistic catalysis

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

• step, photon energy caused an electron transition from the valence to the conduction band in gCN. In the next step, hot electron acted as a scavenger of the terminal proton of the alkyl-/arylacetylenes in order to facilitate the construction of the copper acetanilide species. In the next example

Recent developments in photoredox-catalyzed remote ortho and para C–H bond functionalizations

• Rafia Siddiqui and
• Rashid Ali

Beilstein J. Org. Chem. 2020, 16, 248–280, doi:10.3762/bjoc.16.26

• transition metal catalysis. Mechanism for the formation of 21 from 19 using photoredox catalyst 11. Mechanism for the formation of 30 from acetanilide derivatives. Mechanism for the photoredox-catalyzed synthesis of fluorenone derivatives. Plausible mechanism for the construction of benzothiazoles from

An overview on recent advances in the synthesis of sulfonated organic materials, sulfonated silica materials, and sulfonated carbon materials and their catalytic applications in chemical processes

• Hashem Sharghi,
• Pezhman Shiri and
• Mahdi Aberi

Beilstein J. Org. Chem. 2018, 14, 2745–2770, doi:10.3762/bjoc.14.253

• intermediate IV. Finally, this intermediate is split by a nucleophilic attack of hydroxyl radicals to afford byproducts (including acetic acid, acetanilide, and formic acid) and desired product. The proposed mechanism was confirmed by EPR spectrum. The SSA catalyst is an inexpensive and reusable solid acid

A challenging redox neutral Cp*Co(III)-catalysed alkylation of acetanilides with 3-buten-2-one: synthesis and key insights into the mechanism through DFT calculations

• Andrew Kenny,
• Alba Pisarello,
• Arron Bird,
• Paula G. Chirila,
• Alex Hamilton and
• Christopher J. Whiteoak

Beilstein J. Org. Chem. 2018, 14, 2366–2374, doi:10.3762/bjoc.14.212

• functionalisation approach in 43% yield from the Cp*Rh(III)-catalysed coupling of allylic alcohols with acetanilide through a redox-active mechanism (Scheme 1b) [21], thus requiring stoichiometric oxidant (Cu(OAc)2), whereas the new protocol described in this report is intended to provide a more attractive redox

• as substrates. Results and Discussion Initial investigations into the Cp*Co(III)-catalysed coupling of acetanilide (1a) with 3-buten-2-one, using the optimised conditions for the same coupling previously reported with benzamides, provided poor yields (18%; Scheme 2a). Subsequent reaction condition

• of acetanilide with ethyl acrylate under Cp*Co(III) catalysis [14]. To the best of our knowledge, this is the first time that 3-buten-2-one has been successfully coupled to acetanilide through metal-mediated C–H functionalisation and provides a redox-neutral alternative, with enhanced yield, to the

Palladium-catalyzed ortho-halogenations of acetanilides with N-halosuccinimides via direct sp² C–H bond activation in ball mills

• Zi Liu,
• Hui Xu and
• Guan-Wu Wang

Beilstein J. Org. Chem. 2018, 14, 430–435, doi:10.3762/bjoc.14.31

• corresponding N-halosuccinimides. Keywords: acetanilide; ball milling; C–H activation; halogenation; mechanochemistry; N-halosuccinimide; palladium catalysis; Introduction Aryl halides have been widely utilized in organic syntheses, which give access to a range of complex natural products [1][2]. However

• hindered ortho-position and gave product 2c in 85% yield (Table 2, entry 3). The unsubstituted acetanilide provided the desired product 2d in 77% yield (Table 2, entry 4). It is worth mentioning that the presence of a potentially reactive group, such as fluoro, chloro, and bromo substituents in the

• acetanilides was tolerable, and products 2e–i were isolated in 51–94% yields (Table 2, entries 5–9), highlighting the functional group compatibility of the current protocol. The presence of an acetyl group at the para-position of the phenyl ring of acetanilide 1j decreased the yield of the corresponding

CF₃SO₂X (X = Na, Cl) as reagents for trifluoromethylation, trifluoromethylsulfenyl-, -sulfinyl- and -sulfonylation. Part 1: Use of CF₃SO₂Na

• Hélène Guyon,
• Hélène Chachignon and
• Dominique Cahard

Beilstein J. Org. Chem. 2017, 13, 2764–2799, doi:10.3762/bjoc.13.272

A novel synthetic approach to hydroimidazo[1,5-b]pyridazines by the recyclization of itaconimides and HPLC–HRMS monitoring of the reaction pathway

• Dmitry Yu. Vandyshev,
• Khidmet S. Shikhaliev,
• Andrey Yu. Potapov,
• Michael Yu. Krysin,
• Fedor I. Zubkov and
• Lyudmila V. Sapronova

Beilstein J. Org. Chem. 2017, 13, 2561–2568, doi:10.3762/bjoc.13.252

• ). To confirm the presence of the last six-membered pyridazine ring in the structure and, accordingly, the exocyclic acetanilide residue, it is first of all necessary to make a strict assignment of the carbonyl carbon atom signals at around 170 ppm. In the 1H NMR spectra of imidazopyridazines 9a–g

• water present in the solvent. As no cross-peaks with protons of another methylene group are observed due to a significant number of bonds between them, the acetanilide moiety must be in the exo-position to the pyridazine ring. One of the remaining protons (3.32 ppm) correlates with the carbonyl C atom

Homologated amino acids with three vicinal fluorines positioned along the backbone: development of a stereoselective synthesis

• Raju Cheerlavancha,
• Ahmed Ahmed,
• Yun Cheuk Leung,
• Aggie Lawer,
• Qing-Quan Liu,
• Marina Cagnes,
• Hee-Chan Jang,
• Xiang-Guo Hu and
• Luke Hunter

Beilstein J. Org. Chem. 2017, 13, 2316–2325, doi:10.3762/bjoc.13.228

• reductions to arylamines were successful, an alternative approach was investigated in which the nitroarene group would be converted into the corresponding acetanilide 43. If this approach were successful, it was envisaged that the acetanilide 43 could be directly oxidised to carboxylic acid 44, thereby

• bypassing any diazotization process. Hydrogenation of 41 with 10% Pd/C in the presence of acetic anhydride allowed the isolation of acetanilide 43 in moderate yields (Table 2, entries 4−6). It was found that the acetic anhydride solvent needed to be freshly distilled in every case in order for the reaction

• ). Thus, compound 40a was dissolved in freshly distilled acetic anhydride and subjected to hydrogenation over Pd/C (Scheme 4). The reaction was monitored by TLC at short time intervals in order to avoid over-reduction. The starting material was consumed within 5 h, but the expected acetanilide product

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

• developed a mechanochemical synthesis of an indole moiety via a Rh-catalyzed C–H functionalization strategy under planetary ball mill [187]. Using acetanilide and diphenylacetylene as the alkyne component in presence of 5 mol % Rh catalyst and 2.5 mol % Cu(OAc)2 and 1 atm O2 as terminal oxidant they could

TBHP-mediated highly efficient dehydrogenative cross-oxidative coupling of methylarenes with acetanilides

• Cui Chen,
• Weibing Liu and
• Peng Zhou

Beilstein J. Org. Chem. 2016, 12, 2250–2255, doi:10.3762/bjoc.12.217

• ). Results and Discussion We began by studying the reaction of toluene (1a) and acetanilide (2a) as model substrates to identify the optimal conditions (Table 1). In the presence of I2 (0.1 equiv) and tert-butyl hydroperoxide (TBHP, 2.0 equiv), the study commenced to optimize the reaction time (Table 1

• desired N-arylbenzamides in moderate yields, from 51% to 69% (Table 2, entries 12–14). It is noteworthy that the reactions did not result in the desired product when using aniline and diethylamine as the partners of acetanilide. In order to gain insight into the nature of this conversion, two experiments

Cationic Pd(II)-catalyzed C–H activation/cross-coupling reactions at room temperature: synthetic and mechanistic studies

• Takashi Nishikata,
• Alexander R. Abela,
• Shenlin Huang and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2016, 12, 1040–1064, doi:10.3762/bjoc.12.99

• . Although the combination of acetanilide together with a palladium(II) catalyst lead to the corresponding palladacycle, as reported by Tremont [172], in the presence of 2a, Pd(OAc)2, HBF4 and AgOAc at room temperature, acetyl or isopropyl anilides afford essentially no product. Only after heating to 50 °C

Cross-dehydrogenative coupling for the intermolecular C–O bond formation

• Igor B. Krylov,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2015, 11, 92–146, doi:10.3762/bjoc.11.13

• the selective replacement of one of the two hydrogen atoms in the ortho-position of acetanilide; the molar ratio of the C- and O-reagents is close to stoichiometric. The acetoxylation (product 42) and methoxylation (product 43) of N-(2-benzoylphenyl)benzamides 41 at the ortho-position of the benzamide

Improving the reactivity of phenylacetylene macrocycles toward topochemical polymerization by side chains modification

• Simon Rondeau-Gagné,
• Jules Roméo Néabo,
• Maxime Daigle,
• Katy Cantin and
• Jean-François Morin

Beilstein J. Org. Chem. 2014, 10, 1613–1619, doi:10.3762/bjoc.10.167

• supramolecular nanotubular structures [33][34][35][36][37][38]. Among other things, we have shown that inversion of the amide group configuration (acetanilide vs benzamide) at two different positions on phenylacetylene macrocycles (PAMs) leads to significant changes of the gelation properties and, consequently

• , on the critical parameters needed for polymerization through 1,4-addition reaction [38]. In fact, the acetanilide configuration provides macrocycles which can barely self-assemble in organic solvents while the benzamide configuration yields macrocycles with much greater gelation properties that allow

On the mechanism of photocatalytic reactions with eosin Y

• Michal Majek,
• Fabiana Filace and
• Axel Jacobi von Wangelin

Beilstein J. Org. Chem. 2014, 10, 981–989, doi:10.3762/bjoc.10.97

• reaction with ethyl propiolate according to the literature protocol [19] but in the absence of eosin Y did not afford any phenanthrene product (Scheme 5). Instead, a Ritter-type reaction proceeded to give the corresponding acetanilide after aqueous work-up which is consistent with the original report by

Recent advances in transition metal-catalyzed Csp²-monofluoro-, difluoro-, perfluoromethylation and trifluoromethylthiolation

• Grégory Landelle,
• Armen Panossian,
• Sergiy Pazenok,
• Jean-Pierre Vors and
• Frédéric R. Leroux

Beilstein J. Org. Chem. 2013, 9, 2476–2536, doi:10.3762/bjoc.9.287

• trifluoromethoxy group meta to the directing group shuts down the reaction completely. Other directing groups were investigated. When hydrogen was replaced by methyl on nitrogen in the starting acetanilide, no reaction occurred; on the other hand, N-pivaloyl- and N-benzoylanilines were trifluoromethylated, albeit

• with lower yields than acetanilide. From the study of kinetic isotope effects in several experiments as well as of a Pd-insertion complex similarly to the work of J.-Q. Yu et al., the authors proposed a Pd(II)/Pd(IV) catalytic cycle starting with C–H activation of the substrate followed by oxidation of

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

• trapping of diastereomers of an N-(2-cyclohexenyl)acetanilide derivative is interesting (Scheme 19). One isomer undergoes direct phosphination while the other cyclizes prior to phosphination. Intermolecular phosphinative radical addition of alkyl iodides to activated alkenes proceeds in the presence of

Use of 3-[¹⁸F]fluoropropanesulfonyl chloride as a prosthetic agent for the radiolabelling of amines: Investigation of precursor molecules, labelling conditions and enzymatic stability of the corresponding sulfonamides

• Reik Löser,
• Steffen Fischer,
• Achim Hiller,
• Martin Köckerling,
• Uta Funke,
• Aurélie Maisonial,
• Peter Brust and
• Jörg Steinbach

Beilstein J. Org. Chem. 2013, 9, 1002–1011, doi:10.3762/bjoc.9.115

• restricted to amides derived from aromatic amines [47]. This catalytic activity is crucial for the bioactivation of the acetanilide class of analgesic agents represented by paracetamol as the most important member [48]. Metabolic instability was also observed for aliphatic 18F-labelled fluoroacetamides [13