Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles

• Periklis X. Kolagkis,
• Eirini M. Galathri and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36

A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

• Kathryn M. Wolfe,
• Shahidul Alam,
• Eva German,
• Fahad N. Alduayji,
• Maryam Alqurashi,
• Frédéric Laquai and
• Gregory C. Welch

Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119

• deviation. All of the devices are comparable to the PFN-Br CIL, which is the one that is employed the most for PM6:Y6 OPVs. PFN-Br is most often processed from methanol [32], which is a solvent that is not well suited for the production of large-area or environmentally friendly devices owing to a high vapor

• pressure that can lead to precipitation during coating and due to being a highly flammable and toxic solvent [20][33][34]. Figure S33 in Supporting Information File 1 compares the J–V characteristics of all N-annulated perylene diimides-based CILs cast from ethyl acetate and PFN-Br cast from methanol

Friedel–Crafts acylation of benzene derivatives in tunable aryl alkyl ionic liquids (TAAILs)

• Swantje Lerch,
• Stefan Fritsch and
• Thomas Strassner

Beilstein J. Org. Chem. 2023, 19, 212–216, doi:10.3762/bjoc.19.20

• proved to be a remarkable class of compounds due to their high thermal and chemical stability, their negligible vapor pressure and high versatility in terms of chemical structure and usage [21][22][23][24]. Successive research for the Friedel–Crafts acylation lead to the development of various reaction

First example of organocatalysis by cathodic N-heterocyclic carbene generation and accumulation using a divided electrochemical flow cell

• Daniele Rocco,
• Ana A. Folgueiras-Amador,
• Richard C. D. Brown and
• Marta Feroci

Beilstein J. Org. Chem. 2022, 18, 979–990, doi:10.3762/bjoc.18.98

• coordinated cations and anions, usually bulky organic cations and inorganic or organic anions such as −BF4, −PF6, −N(CF3SO2)2, etc. [2][3]. The physicochemical properties of RTILs (room temperature ionic liquids) are reported in the literature and include very low vapor pressure, and thus the possibility to

• To investigate the possibility to recycle BMImBF4, the experiment reported in Table 3, entry 1, was replicated, using the same reagents and conditions. Exploiting the low vapor pressure of BMImBF4, (and of ILs in general), the organic solvent was removed under reduced pressure, and after the

Synthesis of odorants in flow and their applications in perfumery

• Merlin Kleoff,
• Paul Kiler and
• Philipp Heretsch

Beilstein J. Org. Chem. 2022, 18, 754–768, doi:10.3762/bjoc.18.76

• classification; most odorants belong to multiple categories. Depending on the vapor pressure and consequently the perceptibility of an odorant on a paper strip (the so called “substantivity”), it can be ordered in a pyramid (Figure 2) as a “top note” (substantivity of up to a few hours), a “middle note

Metal-free glycosylation with glycosyl fluorides in liquid SO₂

• Krista Gulbe,
• Jevgeņija Lugiņina,
• Edijs Jansons,
• Artis Kinens and
• Māris Turks

Beilstein J. Org. Chem. 2021, 17, 964–976, doi:10.3762/bjoc.17.78

• related concept by applying liquid SO2. In contrast to scCO2, liquid SO2 is a polar Lewis acidic solvent and due to its relatively high boiling point (bp −10 °C) and low vapor pressure (ca. 3 bar at 20 °C) it can be easily liquefied and handled in its liquid state [38]. Advantages of liquid SO2 over

Ultrasound-assisted Strecker synthesis of novel 2-(hetero)aryl-2-(arylamino)acetonitrile derivatives

• Emese Gal,
• Luiza Gaina,
• Hermina Petkes,
• Alexandra Pop,
• Castelia Cristea,
• Gabriel Barta,
• Dan Cristian Vodnar and
• Luminiţa Silaghi-Dumitrescu

Beilstein J. Org. Chem. 2020, 16, 2929–2936, doi:10.3762/bjoc.16.242

• using “green” solvents, for example, low vapor pressure solvents such as ionic liquids [3], low volatile solvents such as glycerol, ethylene glycol and its oligomers, or nontoxic water solvent, as well as in heterogeneous media under solvent-free conditions [4]. Other advantages induced by sonication

Oligomeric ricinoleic acid preparation promoted by an efficient and recoverable Brønsted acidic ionic liquid

• Fei You,
• Xing He,
• Song Gao,
• Hong-Ru Li and
• Liang-Nian He

Beilstein J. Org. Chem. 2020, 16, 351–361, doi:10.3762/bjoc.16.34

• designable structure, tunable properties as well as superior solubility [26][27]. Furthermore, the thermal stability and negligible vapor pressure of ILs can facilitate the product separation after reaction. To the best of our knowledge, the IL 1-butylsulfonic-3-methylimidazolium tosylate ([HSO3-BMim]TS) can

Palladium-catalyzed Sonogashira coupling reactions in γ-valerolactone-based ionic liquids

• László Orha,
• József M. Tukacs,
• László Kollár and
• László T. Mika

Beilstein J. Org. Chem. 2019, 15, 2907–2913, doi:10.3762/bjoc.15.284

• arylacetylenes [7][8] having great importance in organic synthetic schemes of the pharmaceutical industry. From the environmental point of view, the Sonogashira reactions are usually performed in fossil-based common organic reaction media having high vapor pressure even at higher temperatures, toxicity

• recently γ-valerolactone [19]. The series of these alternative media can implicitly be continued by ionic liquids (ILs) [20], which have attracted considerable attention, due to their extremely low vapor pressure, good solvating properties, reasonable thermal stability, and easily tuneable physical

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

• handling, and even reusability [34]. Ionic liquids (ILs) have been extensively reported as green solvents in organic transformations, owing to their considerable properties such as the ability to dissolve a wide range of substances, very low vapor pressure, high thermal stability, recyclability, non

Bi-mediated allylation of aldehydes in [bmim][Br]: a mechanistic investigation

• Mrunesh Koli,
• Sucheta Chatterjee,
• Subrata Chattopadhyay and
• Dibakar Goswami

Beilstein J. Org. Chem. 2018, 14, 2198–2203, doi:10.3762/bjoc.14.193

• addressed. In modern era, the development of green chemical routes has become inevitable for sustainable technologies. To this end, RTILs are conceived as eco-friendly solvents due to their low vapor pressure, high stability towards air, moisture and heat, ability to dissolve various substrates, and their

The phenyl vinyl ether–methanol complex: a model system for quantum chemistry benchmarking

• Dominic Bernhard,
• Fabian Dietrich,
• Mariyam Fatima,
• Cristóbal Pérez,
• Hannes C. Gottschalk,
• Axel Wuttke,
• Ricardo A. Mata,
• Martin A. Suhm,
• Melanie Schnell and
• Markus Gerhards

Beilstein J. Org. Chem. 2018, 14, 1642–1654, doi:10.3762/bjoc.14.140

• reservoir close to the valve orifice, operating at 8 Hz. PVE was synthesized as described above and used without further purification. The liquid sample was held in the reservoir at room temperature, which resulted in sufficient vapor pressure (standard boiling point of about 155 °C) for recording the

Steric “attraction”: not by dispersion alone

• Ganna Gryn’ova and
• Clémence Corminboeuf

Beilstein J. Org. Chem. 2018, 14, 1482–1490, doi:10.3762/bjoc.14.125

• would lead to elongated intermolecular distances. This might potentially be one of the reasons why the molecular mechanics force fields, commonly applied to aliphatics (see Introduction), significantly underestimate the liquid density and vapor pressure for long chain linear alkanes [70] and branched

Block copolymers from ionic liquids for the preparation of thin carbonaceous shells

• Sadaf Hanif,
• Bernd Oschmann,
• Dmitri Spetter,
• Muhammad Nawaz Tahir,
• Wolfgang Tremel and
• Rudolf Zentel

Beilstein J. Org. Chem. 2017, 13, 1693–1701, doi:10.3762/bjoc.13.163

• energy is needed to overcome the lattice energy and melt the salt. Ion liquids are also called “green solvents”, because of their low vapor pressure, fire resistance and thermal stability [4]. Beside this, they have a high ionic conductivity, large heat capacity and good thermal and chemical stability [5

• conductivity [16]. There are many different morphologies of carbon achievable, like hallow carbon spheres [17], nanotubes, membranes and fibers [18]. Due to their charged nature the PILs show a low vapor pressure and are non-volatile, leading to high carbon yields [19]. Furthermore, PILs offer the possibility

Identification, synthesis and mass spectrometry of a macrolide from the African reed frog Hyperolius cinnamomeoventris

• Markus Menke,
• Pardha Saradhi Peram,
• Iris Starnberger,
• Walter Hödl,
• Gregory F.M. Jongsma,
• David C. Blackburn,
• Mark-Oliver Rödel,
• Miguel Vences and
• Stefan Schulz

Beilstein J. Org. Chem. 2016, 12, 2731–2738, doi:10.3762/bjoc.12.269

• acid precursor is often oxidized near the end of the chain to form a polar hydroxy acid. The following ring-closure reduces the hydrophilicity of the compound and increases its vapor pressure, making the resulting macrocycle well-suited to serve as a signal [1]. Fatty acid derived macrolactones were

Ionic liquids as transesterification catalysts: applications for the synthesis of linear and cyclic organic carbonates

• Maurizio Selva,
• Alvise Perosa,
• Sandro Guidi and
• Lisa Cattelan

Beilstein J. Org. Chem. 2016, 12, 1911–1924, doi:10.3762/bjoc.12.181

• reactions, Friedel–Crafts alkylations and acylations are successfully promoted by ILs [25][26]. The key to such a flourishing research lies in the unique physical properties (negligible vapor pressure, wide liquid range, and non-flammability) of ILs, but mostly on the virtually infinite number of different

Conjugates of methylated cyclodextrin derivatives and hydroxyethyl starch (HES): Synthesis, cytotoxicity and inclusion of anaesthetic actives

• Lisa Markenstein,
• Antje Appelt-Menzel,
• Marco Metzger and
• Gerhard Wenz

Beilstein J. Org. Chem. 2014, 10, 3087–3096, doi:10.3762/bjoc.10.325

• measurement of the vapor pressure of the sevoflurane by gas chromatography as a function of the CD concentration as already described previously [14][52]. The respective occupancies of the hosts occupancies (the molar ratios of complexed guest vs. host) are listed in Table 2. While native β-CD shows only a

• sevoflurane. The vapor pressure of sevoflurane was determined by head space gas chromatography with a Shimadzu GC-17A GC equipped with a head space unit from Shimadzu, Japan. Vials of 5 mL volume were used, the ratio between gas (V = 3.2 mL) and aqueous (V = 1.8 mL) phase was f = 1.77. Occupancies were

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

• biocides (e.g., increased aqueous solubility and wettability, reduced vapor pressure, etc.), ii) the controlled release and bioavailability, iii) the shelf-life, iv) the storage conditions and the environmental toxicity, and v) the biocidal property of textiles which is one of the main fields of

Electrocarboxylation: towards sustainable and efficient synthesis of valuable carboxylic acids

• Roman Matthessen,
• Jan Fransaer,
• Koen Binnemans and
• Dirk E. De Vos

Beilstein J. Org. Chem. 2014, 10, 2484–2500, doi:10.3762/bjoc.10.260

• ]. Their negligible vapor pressure, large electrochemical window, good intrinsic conductivity and high CO2 solubility make them interesting solvents for electrochemical CO2 valorization [81][82][83][99][100][101]. Under similar conditions, ketones are carboxylated with higher selectivity for the α-hydroxy

Efficient CO₂ capture by tertiary amine-functionalized ionic liquids through Li⁺-stabilized zwitterionic adduct formation

• Zhen-Zhen Yang and
• Liang-Nian He

Beilstein J. Org. Chem. 2014, 10, 1959–1966, doi:10.3762/bjoc.10.204

• . These efforts include the development of liquid and solid absorbents and membranes [2][3][4][5][6][7]. Ionic liquids (ILs), which have attractive properties such as negligible vapor pressure, a wide liquid temperature ranges, good thermal stability, high ionic conductivity, and versatile solvation

Space filling of β-cyclodextrin and β-cyclodextrin derivatives by volatile hydrophobic guests

• Sophie Fourmentin,
• Anca Ciobanu,
• David Landy and
• Gerhard Wenz

Beilstein J. Org. Chem. 2013, 9, 1185–1191, doi:10.3762/bjoc.9.133

• indirectly by the reduction of its vapor pressure due to complexation. This HS-GC method is applicable for a great variety of volatile guests [37]. The aim of this study was to investigate the binding ability of β-CD-thioethers toward hydrophobic VOCs in comparison to commercial β-CDs and to interpret the

• constants strongly increase with the amount of space filling of the CD cavity and the salt concentration. β-CD thioethers show a 3–10 times higher binding potential than native β-CD. Keywords: cyclodextrins; inclusion compound; molecular modelling; space filling; static headspace gas chromatography; vapor

• pressure; Introduction β-Cyclodextrin (β-CD, 1), the cyclic α(1→4) heptamer of glucose, is known to form inclusion compounds with a great variety of guests [1], such as derivatives of benzene [2][3], cyclohexane [4], adamantane [5][6], other alicyclic guests [7], and also inorganic molecules or ions [1][8

Polysiloxane ionic liquids as good solvents for β-cyclodextrin-polydimethylsiloxane polyrotaxane structures

• Narcisa Marangoci,
• Rodinel Ardeleanu,
• Laura Ursu,
• Constanta Ibanescu,
• Maricel Danu,
• Mariana Pinteala and
• Bogdan C. Simionescu

Beilstein J. Org. Chem. 2012, 8, 1610–1618, doi:10.3762/bjoc.8.184

• damaging them, through the use of partial water vapor pressure in the microscope specimen chamber. Samples preparation A holey-carbon-coated copper grid was placed on a TEM sample holder and positioned on a Peltier cooling stage. The samples were diluted in THF, and then a small amount of solution was

Intramolecular hydroxycarbene C–H-insertion: The curious case of (o-methoxyphenyl)hydroxycarbene

• Dennis Gerbig,
• David Ley,
• Hans Peter Reisenauer and
• Peter R. Schreiner

Beilstein J. Org. Chem. 2010, 6, 1061–1069, doi:10.3762/bjoc.6.121

• used without further purification. For matrix isolation studies, the sample was cooled to −35 °C to reduce its vapor pressure. Computational methods All computations were performed with the Gaussian09 [27] or Cfour suite [28] of programs. All structures were computed employing the M06 density

Insights into the mechanical properties of a silicone oil gel with a ‘latent’ gelator, 1-octadecylamine, and CO₂ as an ‘activator’

• Emiliano Carretti,
• Mathew George and
• Richard G. Weiss

Beilstein J. Org. Chem. 2010, 6, 984–991, doi:10.3762/bjoc.6.111

• LMOG, 1-octadecylamine (ODA), and a triatomic molecular ‘activator’, carbon dioxide, with silicone oil, tetramethyltetraphenyltrisiloxane, as the liquid component [10][11]. This liquid has been selected because its very low vapor pressure avoids a potential complication, i.e., evaporation of a portion

Flow through reactors for organic chemistry: directly electrically heated tubular mini reactors as an enabling technology for organic synthesis

• Ulrich Kunz and
• Thomas Turek

Beilstein J. Org. Chem. 2009, 5, No. 70, doi:10.3762/bjoc.5.70

• ][20][21][22][23][24]. The reaction scheme for the model reaction is given in Scheme 1. This reaction was chosen for several reasons: Due to the low boiling point of the ester (32 °C) kinetic measurements in traditional equipment are limited to an upper temperature of about 25 °C, otherwise the vapor

• pressure would lead to loss of reactant in an open system. Measurements at temperatures higher than 32 °C are not possible at all. The progress of the reaction can be measured easily online by determining the electrical conductivity of the reaction mixture leaving the reactor. Electrical conductivity is