Cs₂CO₃-Promoted reaction of tertiary bromopropargylic alcohols and phenols in DMF: a novel approach to α-phenoxyketones

• Ol'ga G. Volostnykh,
• Olesya A. Shemyakina,
• Anton V. Stepanov and
• Igor' A. Ushakov

Beilstein J. Org. Chem. 2022, 18, 420–428, doi:10.3762/bjoc.18.44

• 1b with p-nitrophenol (2d, DMF/H2O, 50–55 °C, 3 h) furnished product 8b (14% yield) along with phenoxyhydroxyketone 4k (78% isolated yield). Bromopropargylic alcohol 1c having a tert-butyl group reacted with phenol (2a) in DMF for 3 h to give phenoxyhydroxyketone 4l in only 34% yield, 5

• acidic than phenols 2a–c,f–i (pKa values: 9.99 [25][26] phenol (2a), 9.40 [27] α-naphthol (2b), 9.57 [27] β-naphthol (2c), 7.18 [25][26] p-nitrophenol (2d), 7.23 [25][26] o-nitrophenol (2e), 10.28 [25][26] p-cresol (2f), 10.27 [25][26] p-methoxyphenol (2g), 9.36 [25][26] p-bromophenol (2h), 10.19 eugenol

Regioselective chemoenzymatic syntheses of ferulate conjugates as chromogenic substrates for feruloyl esterases

• Olga Gherbovet,
• Fernando Ferreira,
• Apolline Clément,
• Mélanie Ragon,
• Julien Durand,
• Sophie Bozonnet,
• Michael J. O'Donohue and
• Régis Fauré

Beilstein J. Org. Chem. 2021, 17, 325–333, doi:10.3762/bjoc.17.30

• natural or synthetic compounds [9][10]. The latter, which are used in high-throughput screening (HTS) assays, fall into three categories. The simplest are feruloyl esters of chromogenic moieties [11][12][13][14], such as p-nitrophenol or short-chain alkyl groups (e.g., methyl ferulate). More elaborate and

Synthesis of aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers through the base-mediated reaction between phenols and halothane

• Yukiko Karuo,
• Ayaka Kametani,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2021, 17, 89–96, doi:10.3762/bjoc.17.9

• phenol, p-methoxyphenol (1b) was used, the reaction proceeded to afford ether 2b in 79% yield (Table 2, entry 1). An ortho-substitution with the bulkier tert-butyl group slightly affected the reaction giving product 2c in still acceptable yield (47%, Table 2, entry 2). p-Nitrophenol (1d), which is an

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

Anomeric modification of carbohydrates using the Mitsunobu reaction

• Julia Hain,
• Patrick Rollin,
• Werner Klaffke and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2018, 14, 1619–1636, doi:10.3762/bjoc.14.138

• photoswitchable azobenzene α-D-mannoside 47 (Scheme 9) [46]. Notably, in this reaction, traces of an anomeric mixture of the respective furanoside 48 were detected. The Mitsunobu synthesis of aryl glycosides was also applied to p-nitrophenol [47], naphthols [48][49], or multifunctional phenols [27][50]. Such

Phosphodiester models for cleavage of nucleic acids

• Satu Mikkola,
• Tuomas Lönnberg and
• Harri Lönnberg

Beilstein J. Org. Chem. 2018, 14, 803–837, doi:10.3762/bjoc.14.68

Structure–efficiency relationships of cyclodextrin scavengers in the hydrolytic degradation of organophosphorus compounds

• Sophie Letort,
• Michaël Bosco,
• Benedetta Cornelio,
• Frédérique Brégier,
• Sébastien Daulon,
• Géraldine Gouhier and
• François Estour

Beilstein J. Org. Chem. 2017, 13, 417–427, doi:10.3762/bjoc.13.45

• organophosphorus compound into p-nitrophenol compared to IBA alone. Compound 2 was the most effective, while the slowest pesticide hydrolysis was observed in the presence of derivative 3. These results provided evidence that the relative position of the reactive group towards the phosphorus atom and the vicinity

• . For both studied concentrations (0.25 and 0.5 mM), the catalysts 1–3 were poisoned by the formed p-nitrophenol after a determined time. This phenomenon was already observed: the inclusion of the hydrolysis product in the cyclodextrin cavity limits the catalyst regeneration [27]. Additional

• –4 are fully active over the first 4 minutes. The absorbance increases linearly, thus indicating that no competitive inclusion of p-nitrophenol occurs as a side reaction and the catalyst is prevented from poisoning. In the presence of the most active compound 2, 19.6% of paraoxon were hydrolyzed

Interactions between cyclodextrins and cellular components: Towards greener medical applications?

• Loïc Leclercq

Beilstein J. Org. Chem. 2016, 12, 2644–2662, doi:10.3762/bjoc.12.261

• and Pitha reported a study on the interaction of CDs with peptides containing aromatic amino acids [87]. From competitive spectrophotometry measurements, with p-nitrophenol as a competing reagent at pH 7.4, the authors determined the stability constants of aromatic amino acids and their oligopeptides

p-Nitrophenyl carbonate promoted ring-opening reactions of DBU and DBN affording lactam carbamates

• Madhuri Vangala and
• Ganesh P Shinde

Beilstein J. Org. Chem. 2016, 12, 2086–2092, doi:10.3762/bjoc.12.197

• corresponding carbonates (Table 1, 2a–5a) in good to excellent yields. Subsequently, the purified carbonates dissolved in THF were treated with 2 equiv of DBU. Heating the reaction mixture to 60 °C for 1 h gave the caprolactam carbamate products 2b–5b along with p-nitrophenol as byproduct. In case of the ε

• if the reaction favors both – nucleophilic addition as well as substitution – at lower temperature, the reaction was performed at room temperature for 1.5 h. Although both products were observed the substitution product was minor product, as seen by the integration of p-nitrophenol peaks in the 1H

Scope and limitations of the dual-gold-catalysed hydrophenoxylation of alkynes

• Adrián Gómez-Suárez,
• Yoshihiro Oonishi,
• Anthony R. Martin and
• Steven P. Nolan

Beilstein J. Org. Chem. 2016, 12, 172–178, doi:10.3762/bjoc.12.19

• phenol to 1j (1:0.18), but better than the addition of p-nitrophenol (2v, 1:0.35), both reported in our previous study (3jt and 3jv, Scheme 4) [24]. Finally, we tested whether terminal alkynes were tolerated by our methodology. Phenylacetylene (1k) was reacted with phenol (2t) under our standard reaction

Orthogonal dual-modification of proteins for the engineering of multivalent protein scaffolds

• Michaela Mühlberg,
• Michael G. Hoesl,
• Christian Kuehne,
• Jens Dernedde,
• Nediljko Budisa and
• Christian P. R. Hackenberger

Beilstein J. Org. Chem. 2015, 11, 784–791, doi:10.3762/bjoc.11.88

• lectin binding studies To ensure the stability of TTL throughout the dual-labeling process, we performed a lipase activity assay to demonstrate that the enzymatic activity could be retained. All protein samples thereby showed similar lipase activity, as determined by the colorimetric p-nitrophenol assay

• the same volume of 50 mM Tris·HCl pH 8.0 instead of enzyme (background measurement). The samples were shaken at 50 °C for 1 h. Absorbance of released p-nitrophenol was measured at λ = 410 nm (Figure S10, Supporting Information File 1). Surface-plasmon-resonance (SPR). SPR measurements were performed

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

• Véronique Nardello-Rataj and
• Loïc Leclercq

Beilstein J. Org. Chem. 2014, 10, 2603–2622, doi:10.3762/bjoc.10.273

• and silver nanoparticles. The resulting material was fully characterized and the antibacterial properties using spiked water samples containing E. coli and Salmonella typhi were evaluated in the presence of p-nitrophenol (organic pollutant). The material based on polyurethanes reduced up to 3 logs of

• bacteria and adsorbed up to 55% of p-nitrophenol pollutant. It is worth mentioning that single-walled carbon nanotubes already exhibit a strong antimicrobial activity because of the piercing of the bacterial cell membranes (Scheme 10) [94]. Therefore, their combination with biocidal nanoparticles allows a

Continuous flow nitration in miniaturized devices

• Amol A. Kulkarni

Beilstein J. Org. Chem. 2014, 10, 405–424, doi:10.3762/bjoc.10.38

• , pharmaceuticals, fuel additives, antioxidants, and rubber accelerators. In the leather industry m-nitrophenol is used as a fungicide and p-nitrophenol as a chemical intermediate for leather preservatives. 2,4-Dinitrophenol is useful for the manufacturing of photographic developers and serves as a wood

Simple and rapid hydrogenation of p-nitrophenol with aqueous formic acid in catalytic flow reactors

• Rahat Javaid,
• Shin-ichiro Kawasaki,
• Akira Suzuki and
• Toshishige M. Suzuki

Beilstein J. Org. Chem. 2013, 9, 1156–1163, doi:10.3762/bjoc.9.129

• produced a porous Pd surface. Hydrogenation of p-nitrophenol was examined in the presence of formic acid simply by passing the reaction solution through the catalytic tubular reactors. p-Aminophenol was the sole product of hydrogenation. No side reaction occurred. Reaction conversion with respect to p

• -nitrophenol was dependent on the catalyst layer type, the temperature, pH, amount of formic acid, and the residence time. A porous and oxidized Pd (PdO) surface gave the best reaction conversion among the catalytic reactors examined. p-Nitrophenol was converted quantitatively to p-aminophenol within 15 s of

• residence time in the porous PdO reactor at 40 °C. Evolution of carbon dioxide (CO2) was observed during the reaction, although hydrogen (H2) was not found in the gas phase. Dehydrogenation of formic acid did not occur to any practical degree in the absence of p-nitrophenol. Consequently, the nitro group

Inclusion of the insecticide fenitrothion in dimethylated-β-cyclodextrin: unusual guest disorder in the solid state and efficient retardation of the hydrolysis rate of the complexed guest in alkaline solution

• Dyanne L. Cruickshank,
• Natalia M. Rougier,
• Raquel V. Vico,
• Susan A. Bourne,
• Elba I. Buján,
• Mino R. Caira and
• Rita H. de Rossi

Beilstein J. Org. Chem. 2013, 9, 106–117, doi:10.3762/bjoc.9.14

• the presence of OH in the rim of the cavity has an important role in determining the orientation of the included guest molecule. Based on the fact that the ICD spectra of p-nitrophenol and fenitrothion are similar, Kamiya [21] suggested that the inclusion of both compounds should be similar. This is

Facile synthesis of nitrophenyl 2-acetamido-2-deoxy-α-D-mannopyranosides from ManNAc-oxazoline

• Karel Křenek,
• Petr Šimon,
• Lenka Weignerová,
• Barbora Fliedrová,
• Marek Kuzma and
• Vladimír Křen

Beilstein J. Org. Chem. 2012, 8, 428–432, doi:10.3762/bjoc.8.48

• ] affording oxazoline 3 in 75% yield. The glycosylation of phenol and p-nitrophenol with oxazoline 3 was extensively tested. We tested a large array of reaction conditions, including variation of catalyst (copper(II) chloride [12][15], 2,2-diphenyl-1-picrylhydrazyl, zinc chloride, tin(IV) chloride) and

• also tested with p-nitrophenol; however, the required p-nitrophenyl glycoside 6 was produced under these conditions only in trace amounts (observed by TLC). Our and previously published results [11] indicate that the deactivation of phenol by the electron-withdrawing nitro group substantially decreases

Kinetic studies and predictions on the hydrolysis and aminolysis of esters of 2-S-phosphorylacetates

• Milena Trmčić and
• David R. W. Hodgson

Beilstein J. Org. Chem. 2010, 6, 732–741, doi:10.3762/bjoc.6.87

• (5 mL) was added dropwise to a stirred solution of bromoacetyl bromide (0.38 mL, 4.3 mmol) in dry DCM (5 mL) cooled in an ice bath. Following the careful addition of p-nitrophenol (0.6 g, 4.3 mmol), the reaction mixture was stirred for 1 h. Saturated sodium bicarbonate solution (5 mL) was added, the

• (125 MHz; CDCl3) 165.2 (C=O), 155.1 (CO), 145.9 (CNO2), 125.6 (NO2CCH), 122.4 (CHCO), 25.3 (CH2Br); m/z (EI) 258.9 and 260.9. m-Nitrophenyl 2-bromoacetate 1 (R = mNP) The procedure for p-nitrophenyl 2-bromoacetate 1 (R = pNP) was followed except p-nitrophenol was replaced by m-nitrophenol (0.6 g, 4.3

(Pseudo)amide-linked oligosaccharide mimetics: molecular recognition and supramolecular properties

• José L. Jiménez Blanco,
• Fernando Ortega-Caballero,
• Carmen Ortiz Mellet and
• José M. García Fernández

Beilstein J. Org. Chem. 2010, 6, No. 20, doi:10.3762/bjoc.6.20

• , Kessler and co-workers have reported the synthesis of cyclic oligomers containing glucopyranosyluronic acid by exploiting standard solid and solution phase coupling procedures [54]. These cyclic homo-oligomers of SAAs behave as host molecules that form inclusion complexes with p-nitrophenol and benzoic

The Elbs and Boyland- Sims peroxydisulfate oxidations

• E. J. Behrman

Beilstein J. Org. Chem. 2006, 2, No. 22, doi:10.1186/1860-5397-2-22

• hydroperoxide forms p-nitrophenol on decomposition. Similarly, Malykhin and Shteingarts found naphthols as products from the reaction of potassium peroxide with several nitronaphthalenes. [19] These findings are then consistent with the hypothesis that aryl hydroperoxides formed by reaction of arylphenoxide

• -like materials. [1] Also, displacement of substituents by ipso attack has been reported for R = -Cl [27], -I[28], -COOH[29], and -NO2 in the case of p-nitrophenol. [16] Future directions Peroxydisulfate is a very versatile oxidant as recent reviews have pointed out. [30][31] An important developing