Solvent-free and room temperature synthesis of 3-arylquinolines from different anilines and styrene oxide in the presence of Al₂O₃/MeSO₃H

• Hashem Sharghi,
• Mahdi Aberi,
• Mohsen Khataminejad and
• Pezhman Shiri

Beilstein J. Org. Chem. 2017, 13, 1977–1981, doi:10.3762/bjoc.13.193

• been developed in the presence of Al2O3/MeSO3H via one-pot reaction of anilines and styrene oxide. This methodology provides very rapid access to 3-arylquinolines in good to excellent yields under solvent-free conditions at room temperature in air. Keywords: 3-arylquinolines; Al2O3; MeSO3H; one-pot

• anilines with styrene oxide via C–C cleavage is the efficient synthetic route to quinolones [1]. The reaction was performed using FeCl3 as catalyst in 1,4-dioxane as solvent at 110 °C for 12 h. According to the significance of this progress, we have decided to re-optimize it. The mixture of Al2O3 and

• optimized conditions for the synthesis of quinolines, the reaction of 3,4-dimethylaniline (1, 1.0 mmol) and styrene oxide (2, 2.0 mmol) in an open atmosphere was chosen as a model reaction (Table 1). Control experiments showed that in the absence of Al2O3 and MeSO3H, no quinoline 3a was observed (Table 1

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

• triazole moiety (Scheme 37a) using benzyl halides, sodium azide and a terminal alkyne via an alumina-supported copper catalyst. Using 10 mol % of Cu/Al2O3, differently substituted phenyl acetylenes and aliphatic alkynes led to 70–96% yield of triazoles [152]. Phenyl boronic acids were also used to

• dialkyl carbonates [90]. Mechanochemical transesterification reaction using basic Al2O3 [91]. Mechanochemical carbamate synthesis [92]. Mechanochemical bromination reaction using NaBr and oxone [96]. Mechanochemical aryl halogenation reactions using NaX and oxone [97]. Mechanochemical halogenation

Solvent-free sonochemistry: Sonochemical organic synthesis in the absence of a liquid medium

• Deborah E. Crawford

Beilstein J. Org. Chem. 2017, 13, 1850–1856, doi:10.3762/bjoc.13.179

• presence of KCN/Al2O3, is an example of organic synthesis employing ultrasound [17]. Interestingly, the conventional solution method results in the alkylation of the toluene aromatic ring, however, when sonication is employed, a reaction between benzyl bromide and KCN occurs producing PhCH2CN, indicating

Encaging palladium(0) in layered double hydroxide: A sustainable catalyst for solvent-free and ligand-free Heck reaction in a ball mill

• Wei Shi,
• Jingbo Yu,
• Zhijiang Jiang,
• Qiaoling Shao and
• Weike Su

Beilstein J. Org. Chem. 2017, 13, 1661–1668, doi:10.3762/bjoc.13.160

• silica gel is considered as the most effective choice for the reaction (Table 2, entry 1), but MgAl-LDHs gave also a good result (Table 2, entry 5). With NaCl, α-Al2O3 and γ-Al2O3, the yields were unsatisfactory (Table 2, entries 2–4). Increasing or decreasing the amount of silica gel would led to a

Sugar-based micro/mesoporous hypercross-linked polymers with in situ embedded silver nanoparticles for catalytic reduction

• Qing Yin,
• Qi Chen,
• Li-Can Lu and
• Bao-Hang Han

Beilstein J. Org. Chem. 2017, 13, 1212–1221, doi:10.3762/bjoc.13.120

• or embed the AgNPs into a supporting matrix. The loading of AgNPs on different substrates has been reported, for instance, SiO2 [23], TiO2 [24], Al2O3 [25], porous carbon [26], carbonaceous matrix [27], carboxymethyl chitosan [28], zeolite [29], cellulose [30], ZnO paper [31] and polymers such as PVP

Continuous-flow processes for the catalytic partial hydrogenation reaction of alkynes

• Carmen Moreno-Marrodan,
• Francesca Liguori and
• Pierluigi Barbaro

Beilstein J. Org. Chem. 2017, 13, 734–754, doi:10.3762/bjoc.13.73

• ” 1% Pd@Al2O3 (Table 1, entry 5) showed to be poorly selective (67%), resulting in considerable amounts of oligomers and over-hydrogenated product 1b [121]. The performance of the above systems was compared with that of a single-site catalyst based on Pd atoms confined into the “six-fold cavities” of

• rate for 1a (0.9 mol gPd−1 h−1) (Table 1, entry 9) [124], that confirms the effectiveness of the strategy. The continuous flow partial hydrogenation of 1-heptyne (2) to 1-heptene (2a), an additive for lubricants and a surfactant [125], was also reported using packed 2% Pd@Al2O3 catalyst, showing 49

• was investigated in detail by comparing the selectivity of diverse Pd packed-bed catalysts at the same substrate conversion level (30%). The study confirmed the efficiency of the catalysts to decrease in the order Pd(HHDMA)@C > Pd(HHDMA)@TiS > Lindlar > Pd@Al2O3 (from 100 to 67%) [121]. This

Continuous N-alkylation reactions of amino alcohols using γ-Al₂O₃ and supercritical CO₂: unexpected formation of cyclic ureas and urethanes by reaction with CO₂

• Emilia S. Streng,
• Darren S. Lee,
• Michael W. George and
• Martyn Poliakoff

Beilstein J. Org. Chem. 2017, 13, 329–337, doi:10.3762/bjoc.13.36

• 10.3762/bjoc.13.36 Abstract The use of γ-Al2O3 as a heterogeneous catalyst in scCO2 has been successfully applied to the amination of alcohols for the synthesis of N-alkylated heterocycles. The optimal reaction conditions (temperature and substrate flow rate) were determined using an automated self

• alcohols using γ-Al2O3 with scCO2 as the solvent and employed self-optimisation [45][46] to explore the defined parameter space to effectively identify the highest yielding and optimal conditions in a relatively short timeframe. Results and Discussion To investigate our hypothesis that γ-Al2O3 with scCO2

• (Scheme 3b, 380 °C at 1 mL min−1), and no imidazolidinone 16 was detected. Conclusion Using a self-optimising reactor and a simple heterogeneous catalyst, γ-Al2O3, moderate to high yields of several alkylated cyclic amines, formed in a two-step intramolecular cyclisation/N-alkyation reaction, using amino

The reductive decyanation reaction: an overview and recent developments

• Jean-Marc R. Mattalia

Beilstein J. Org. Chem. 2017, 13, 267–284, doi:10.3762/bjoc.13.30

• second part of their work, they developed adequate conditions to carry out the decyanation reaction without olefin isomerization [18]. They explored several methods for the preparation of 12-butyltricosa-1,22-diene 3 (R = n-C4H9). The reaction was carried out in a slurry of K/Al2O3 in hexane, hexane

• -BuOH could act as a proton donor and so prevent the olefin isomerization. Alkali metals can also be used in suspension. As mentioned above, highly dispersed potassium over neutral alumina (K/Al2O3) in hexane is able to effect the reductive cleavage of alkylnitriles [18][34]. Zárraga et al. described an

Benzothiadiazole oligoene fatty acids: fluorescent dyes with large Stokes shifts

• Lukas J. Patalag and
• Daniel B. Werz

Beilstein J. Org. Chem. 2016, 12, 2739–2747, doi:10.3762/bjoc.12.270

• , 192.03573; found, 192.03451. (10E,12E)-13-(Benzo[c][1,2,5]thiadiazol-4-yl)tridec-10,12-dienoic acid (7): To a solution of alcohol 6 (160 mg, 0.832 mmol, 1.0 equiv) in DCM (8 mL) was added MnO2 (1.5 g, 16.6 mmol, 20 equiv) at rt. Stirring was continued for 45 min. A mixture of SiO2/Al2O3 (1:1) was added and

• , 0.183 mmol, 1.0 equiv) in DCM (1.5 mL) was added MnO2 (318 mg, 3.66 mmol, 20 equiv) at rt. Stirring was continued for 45 min. A mixture of SiO2/Al2O3 (1:1) was added and the solvent removed to obtain the adsorbed crude product. A short column filtration (20% EtOAc in pentane) gave 34 mg of the

• freshly prepared aldehyde dissolved in THF (1 mL) was added and stirring continued for 1 h at 0 °C. The reaction was quenched with HCOOH (3 equiv) and directly adsorbed on silica/Al2O3 (1:1). Column chromatography (10% EtOAc in pentane to remove rests of aldehyde, then 5% EtOAc, 0.1% HCOOH → 6% EtOAc

Selective synthesis of thioethers in the presence of a transition-metal-free solid Lewis acid

• Federica Santoro,
• Matteo Mariani,
• Federica Zaccheria,
• Rinaldo Psaro and
• Nicoletta Ravasio

Beilstein J. Org. Chem. 2016, 12, 2627–2635, doi:10.3762/bjoc.12.259

• acids, namely 13% Al2O3 on silica (SiAl 13), 4.7% ZrO2 on silica (SiZr 4.7), 2.3% TiO2 on silica (SiTi 2.3) and 0.6% Al2O3 on silica (SiAl 0.6) whose textural properties are summed up in Supporting Information File 1, Table S1. Results are reported in Table 1. It is worth underlining that under these

• . They allow us to set up very selective processes without producing any waste and avoiding the use of toxic substrates or metals. In particular a 0.6% Al2O3 on silica, can be conveniently used for the green synthesis of thioethers starting from aromatic alcohols and aromatic or aliphatic thiols. The

A new and expeditious synthesis of all enantiomerically pure stereoisomers of rosaprostol, an antiulcer drug

• Wiesława Perlikowska,
• Remigiusz Żurawiński and
• Marian Mikołajczyk

Beilstein J. Org. Chem. 2016, 12, 2234–2239, doi:10.3762/bjoc.12.215

• methyl 5-formylpentanecarboxylate was carried out. The use of a mixture of Al2O3 and KOH as a base in this reaction afforded the corresponding olefination products (−)-(R)-5 and (+)-(S)-5 in high yields. Both of them were formed as mixtures of E and Z-isomers. Although these mixtures were directly used

• cyclopentanone 3. Reagents and conditions: (a) Al2O3, SiO2, MS 5 Å, DCM, rt, 5 d; (b) cation exchanger Dowex 50WX4, MeOH/H2O 5:1, rt, 3 N HCl (drops), column chromatography. Synthesis of rosaprostol stereoisomers 1a and 1c. Reagents and conditions: (a) KOH/Al2O3, OHC(CH2)5CO2Me, C6H6, 3 h rt; (b) Te, NaBH4, EtOH

Enantioselective carbenoid insertion into C(sp³)–H bonds

• J. V. Santiago and
• A. H. L. Machado

Beilstein J. Org. Chem. 2016, 12, 882–902, doi:10.3762/bjoc.12.87

• to perform an enantioselective insertion of the carbenoid into benzylic C(sp3)–H bonds and similar results were observed [49]. In 2011, the same research group developed a new heterogeneous copper catalyst for carbenoid insertion into C(sp3)–H bonds [50]. The solid support was based on SiO2/Al2O3 and

Effective immobilisation of a metathesis catalyst bearing an ammonium-tagged NHC ligand on various solid supports

• Krzysztof Skowerski,
• Jacek Białecki,
• Stefan J. Czarnocki,
• Karolina Żukowska and
• Karol Grela

Beilstein J. Org. Chem. 2016, 12, 5–15, doi:10.3762/bjoc.12.2

• ease of handling and product purification. Lower efficiency was observed in the case of catalyst supported on neutral aluminium oxide (8-Al2O3) which provided product 10 in diminished yield. On the other hand, the catalyst supported on unmodified silica gel (8-SiO2) showed the fastest initiation rate

Cu(I)-catalyzed N,N’-diarylation of natural diamines and polyamines with aryl iodides

• Svetlana P. Panchenko,
• Alexei D. Averin,
• Maksim V. Anokhin,
• Olga A. Maloshitskaya and
• Irina P. Beletskaya

Beilstein J. Org. Chem. 2015, 11, 2297–2305, doi:10.3762/bjoc.11.250

• the literature. One of them employs an iridium-based catalyst with amidophosphonate as the ligand which allows to convert aminoalcohols into N-monoaryl-substituted diamines by the reaction with arylamines [20]. Another method uses a bimetallic catalyst (Pt–Sn/γ-Al2O3) in the reactions of diols with

Selected synthetic strategies to cyclophanes

• Sambasivarao Kotha,
• Mukesh E. Shirbhate and
• Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

Intermolecular addition reactions of N-alkyl-N-chlorosulfonamides to unsaturated compounds

• Gerold Heuger and
• Richard Göttlich

Beilstein J. Org. Chem. 2015, 11, 1226–1234, doi:10.3762/bjoc.11.136

• ], which produced the corresponding N-chloro compounds 2a and 2b in quantitative yield (Scheme 1). Other procedures for the synthesis of these compounds including N-chlorination with an fivefold excess of Oxone® in the presence of NaCl/Al2O3 [35] or deprotonation and reaction with NCS [36][37] did not lead

Indolizines and pyrrolo[1,2-c]pyrimidines decorated with a pyrimidine and a pyridine unit respectively

• Marcel Mirel Popa,
• Emilian Georgescu,
• Mino R. Caira,
• Florentina Georgescu,
• Constantin Draghici,
• Raluca Stan,
• Calin Deleanu and
• Florea Dumitrascu

Beilstein J. Org. Chem. 2015, 11, 1079–1088, doi:10.3762/bjoc.11.121

• acetylenic dipolarophiles 10 (3.5 mmol) were stirred under reflux in 20 mL 1,2-epoxybutane for 24 h. The products were precipitated with ethanol and removed by filtration. Further purification was made by crystallization from ethanol or by column chromatography on Al2O3 using methylene chloride as eluent. 3

• . The products were precipitated with ethanol and removed by filtration. Further purification was performed by crystallization from ethanol or column chromatography on Silicagel-60 (Merck) or neutral Al2O3 by using methylene chloride as an eluent. 1-Acetyl-3-benzoyl-7-(4-pyrimidinyl)indolizine (16a

Functionalized branched EDOT-terthiophene copolymer films by electropolymerization and post-polymerization “click”-reactions

• Miriam Goll,
• Adrian Ruff,
• Erna Muks,
• Felix Goerigk,
• Beatrice Omiecienski,
• Ines Ruff,
• Rafael C. González-Cano,
• Juan T. Lopez Navarrete,
• M. Carmen Ruiz Delgado and
• Sabine Ludwigs

Beilstein J. Org. Chem. 2015, 11, 335–347, doi:10.3762/bjoc.11.39

• for several days). Acetonitrile (Alfa Aesar, supergradient HPLC grade (far-UV), +99.9%) was stored over neutral Al2O3 (activated under vacuum at 120 °C for 24 h) under an argon atmosphere. DMSO was distilled in vacuum, crystallized at 4 °C and the mother liquor was removed. After melting of the

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

• with low-molecular-weight alcohols was performed in the presence of heterogeneous catalysts, such as Au/TiO2 [98][99][100], Au/β-Ga2O3 [101], Au/polymer [102], and AuNiOx/SiO2-Al2O3-MgO [103]. In all the above-mentioned processes in the presence of heterogeneous catalysts, low-molecular-weight alcohols

Modification of physical properties of poly(L-lactic acid) by addition of methyl-β-cyclodextrin

• Toshiyuki Suzuki,
• Ayaka Ei,
• Yoshihisa Takada,
• Hiroki Uehara,
• Takeshi Yamanobe and
• Keiko Takahashi

Beilstein J. Org. Chem. 2014, 10, 2997–3006, doi:10.3762/bjoc.10.318

• mg samples placed in an open Al2O3 pan. For the stability test and accuracy of complex mass ratio, the measurements were carried out from 25 to 800 °C. MeCD was used as received. Tensile drawing test Tensile drawing of samples was carried out at 25, 60, and 100 °C using a Tensilon RTC-1325A tensile

Multicomponent reactions in nucleoside chemistry

• Mariola Koszytkowska-Stawińska and
• Włodzimierz Buchowicz

Beilstein J. Org. Chem. 2014, 10, 1706–1732, doi:10.3762/bjoc.10.179

• min; ii. CuSO4·5H2O, Al2O3, microwave irradiation (90 °C), 3–3.5 min. Reagents and reaction conditions: i. PhI(OAc)2 (3 mol %), microwave irradiation (45 °C), 6–9 min. Reagents and reaction conditions: i. 117, ethyl pyruvate, TiCl4, dichloromethane, −78 °C, 1 h; then 118, −78 °C, 1 h; then 23 °C, 1 h

Addition of H-phosphonates to quinine-derived carbonyl compounds. An unexpected C9 phosphonate–phosphate rearrangement and tandem intramolecular piperidine elimination

• Łukasz Górecki,
• Artur Mucha and
• Paweł Kafarski

Beilstein J. Org. Chem. 2014, 10, 883–889, doi:10.3762/bjoc.10.85

• observed reactivity seemed to be general as formation of compound 13b was evidenced (to a different extent) in other variants of the catalytical addition of diethyl phosphite to quininone/quinidinone, with catalytic systems such as: KF/Al2O3, NH3/EtOH and DBU/EtOH or toluene. Independent of the catalyst

Silver and gold-catalyzed multicomponent reactions

• Giorgio Abbiati and
• Elisabetta Rossi

Beilstein J. Org. Chem. 2014, 10, 481–513, doi:10.3762/bjoc.10.46

• , 25 °C for aldimine formation (first step) in the MM K-10 containing packed-bed capillary reactor (PBCR), and 80 °C for the reaction with phenylacetylene (second step) in Au NP@Al2O3 containing PBCR. The system, tested with some different aryl/heteroaryl/alkylaldehydes and cyclic/acyclic secondary

Synthesis, characterization and initial evaluation of 5-nitro-1-(trifluoromethyl)-3H-1λ³,2-benziodaoxol-3-one

• Nico Santschi,
• Roman C. Sarott,
• Elisabeth Otth,
• Reinhard Kissner and
• Antonio Togni

Beilstein J. Org. Chem. 2014, 10, 1–6, doi:10.3762/bjoc.10.1

• . Consequently in light of these results, DSC measurements of 2 and 3 were carried out in order to assess the thermal stability of the new derivative. These measurements were performed in punctured Al2O3 pans with a heating rate of 10 K/min. For reagent 2, a decomposition energy of 138 kJ/mol (438 J/g, slightly

Investigating the continuous synthesis of a nicotinonitrile precursor to nevirapine

• Ashley R. Longstreet,
• Suzanne M. Opalka,
• Brian S. Campbell,
• B. Frank Gupton and
• D. Tyler McQuade

Beilstein J. Org. Chem. 2013, 9, 2570–2578, doi:10.3762/bjoc.9.292

• included two columns: a packed-bed of Al2O3 to catalyze the reaction and a packed bed of 3 Å molecular sieves to absorb water before the addition of DMF-DMA (Scheme 4). The mass of each solid used (2.00 g of Al2O3 and 1.50 g molecular sieves) was chosen based on the size of the available columns. Assuming

• that the Knoevenagel condensation occurred primarily in the Al2O3 column, we only varied the temperature of the Al2O3 column. The Al2O3 column temperature was initially set to 25 °C which yielded 91% of 5 from acetone and malononitrile (Table 2, entry 2). We observed that the Al2O3 column reactor

• are combined the system stability can become an issue. To measure the stability, we ran the reaction under the optimized conditions and monitored the product distribution. When the aforementioned optimized column temperatures were used (20 °C Al2O3 column, 25 °C 3 Å MS column), the alumina column