Functional panchromatic BODIPY dyes with near-infrared absorption: design, synthesis, characterization and use in dye-sensitized solar cells

• Quentin Huaulmé,
• Cyril Aumaitre,
• Outi Vilhelmiina Kontkanen,
• David Beljonne,
• Alexandra Sutter,
• Gilles Ulrich,
• Renaud Demadrille and
• Nicolas Leclerc

Beilstein J. Org. Chem. 2019, 15, 1758–1768, doi:10.3762/bjoc.15.169

• were investigated using UV–vis spectroscopy, and we show that they can absorb light up to 900 nm in solution and 1000 nm in solid state, after grafting on anatase-TiO2 mesoporous films. The cyclic voltammetry (CV) measurements indicate that the compounds have HOMO and LUMO energy levels suitable for an

Synthesis, photophysical and electrochemical properties of pyridine, pyrazine and triazine-based (D–π–)₂A fluorescent dyes

• Keiichi Imato,
• Toshiaki Enoki,
• Koji Uenaka and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2019, 15, 1712–1721, doi:10.3762/bjoc.15.167

• solvents are much larger than those in nonpolar solvents (Table 1). In order to investigate the solid-state photophysical properties of OUY-2, OUK-2 and OUJ-2, we have measured the solid-state fluorescence spectra of the solids (Figure 4). The λmax,fl of the as-recrystallized dyes appears at 550 nm for OUY

• -2, 592 nm for OUK-2, and 557 nm for OUJ-2, which showed a significant bathochromic shift by 97 nm, 112 nm, and 48 nm, respectively, compared with those in toluene. The solid-state Φf value is below 0.02 for OUY-2 and OUK-2 and 0.09 for OUJ-2, which are much lower than those in toluene. It is well

• known that D–π–A fluorescent dyes show bathochromic shifts of the λmax,fl and lower Φf values by changing from the solution state to the solid state. This fact is attributed to the delocalization of excitons or excimers due to the formation of intermolecular π–π interactions [48][49][50][51] between the

Reaction of oxiranes with cyclodextrins under high-energy ball-milling conditions

• László Jicsinszky,
• Federica Calsolaro,
• Katia Martina,
• Fabio Bucciol,
• Maela Manzoli and
• Giancarlo Cravotto

Beilstein J. Org. Chem. 2019, 15, 1448–1459, doi:10.3762/bjoc.15.145

• chemistry. The restricted mobility of solid-state components further reduces the aforementioned side-reactions and enhances the utilization in the CD substitution. Although many side reactions are suppressed in ball milling, they cannot be completely eliminated when alkaline hydroxides are used to activate

• toward MO, as seen in the UV spectra in Figure 6 and Figure 7. However, unlike the epichlorohydrin polymers, their “concentration-dependency” was not linear. The solution and solid state reactions showed similar yields, as can be concluded from Table 5. A significant difference was found between GPTS-β

• -synthesised CD derivatives was simpler in the (2-hydroxy)propylated cases, it does not seem possible to alter the current industrial method to make it more green. Preparations of water-insoluble CD derivatives were more effective than the solution reactions, but the particle size of the solid state reaction

Selenophene-containing heterotriacenes by a C–Se coupling/cyclization reaction

• Pierre-Olivier Schwartz,
• Sebastian Förtsch,
• Astrid Vogt,
• Elena Mena-Osteritz and
• Peter Bäuerle

Beilstein J. Org. Chem. 2019, 15, 1379–1393, doi:10.3762/bjoc.15.138

• crucial cyclization steps to the stable and soluble fused systems were achieved by copper-catalyzed C–S and C–Se coupling/cyclization reactions. Structures and packing motifs in the solid state were elucidated by single crystal X-ray analysis and XRD powder measurements. Comparison of the optoelectronic

• starting material, but also ring fusion to selenophene was achieved by Cu-catalyzed C–Se cross-coupling reaction [28]. The detailed geometric structure and the packing behaviour in the solid state of triacenes 2–4 have been elucidated by single crystal X-ray structure analysis and X-ray diffraction on

Synthesis of dipolar molecular rotors as linkers for metal-organic frameworks

• Sebastian Hamer,
• Fynn Röhricht,
• Marius Jakoby,
• Ian A. Howard,
• Xianghui Zhang,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2019, 15, 1331–1338, doi:10.3762/bjoc.15.132

• also been pursued to implement molecular rotors in the solid state. Crystals of linear molecular rotors [8][9][10][11][12][13], caged rotor crystals and gyroscope like molecules [14][15][16][17][18][19][20] as well as organosilicates [21] and metal-organic frameworks [22][23][24][25] containing

Mechanochemical Friedel–Crafts acylations

• Mateja Đud,
• Anamarija Briš,
• Iva Jušinski,
• Davor Gracin and
• Davor Margetić

Beilstein J. Org. Chem. 2019, 15, 1313–1320, doi:10.3762/bjoc.15.130

• temperature without the use of solvents, which are usually highly toxic (halogenated hydrocarbons) will improve the eco-friendliness of the process. Until now, FCRs have been rarely applied to organic functionalizations which are carried out in solid state by mortar and pestle [3][4][5]. We are aware of only

• forced conditions (by melting at 200 °C) reacted sluggishly with pyrene affording mixture of regioisomeric products 6 and 7. The advantage of the employment of mechanochemical conditions is evidenced by solid state milling of pyrene with succinic anhydride which showed remarkably better performance than

• (<5%) of 22. This result indicates that rapid [4π – 4π] cycloreversion of 19 takes place, even in solid state ball-milling conditions at room temperature. Produced anthracene then subsequently participates in FCR. In control reaction of milling of photodimer 19 itself for 1 h was converted to

Understanding the unexpected effect of frequency on the kinetics of a covalent reaction under ball-milling conditions

• Ana M. Belenguer,
• Adam A. L. Michalchuk,
• Giulio I. Lampronti and
• Jeremy K. M. Sanders

Beilstein J. Org. Chem. 2019, 15, 1226–1235, doi:10.3762/bjoc.15.120

• crystals into smaller particles followed by the accumulation of energy in crystal defects. In recent years, manual and ball-mill grinding have become increasingly routine solid-state synthesis tools [1]. Generally referred to as mechanochemistry, these methods are more environmentally friendly and usually

• developing a fundamental understanding of these solid-state processes. The validation of reaction kinetic models has been a powerful approach for investigating fundamental processes in chemistry and physics. This has led to significant advancement in the understanding of molecular and submolecular phenomena

• ) is the Arrhenius-type rate constant, and f(α) is the functional form of rate, dependent on the specific mechanism of the transformation. Many of the traditional kinetic equations for solid-state transformations (e.g., the Avrami–Erofeyev and Prout–Tompkins models) are derived for single phase solid

Molecular recognition using tetralactam macrocycles with parallel aromatic sidewalls

• Dong-Hao Li and
• Bradley D. Smith

Beilstein J. Org. Chem. 2019, 15, 1086–1095, doi:10.3762/bjoc.15.105

• -conformational motion such as macrocycle pirouetting around the encapsulated guest [50][51]. The Smith group has found that an organic soluble version of anthracene-containing tetralactam B is able to encapsulate squaraine, thiosquaraine and croconaine dyes [33][57][58][59]. Solid-state structures of various

• (left) with anionic square planar metal halide complexes (right). (b) Solid-state structures of B·AuBr4− (X = CH, Z = t-Bu, left) and C·AuBr4− (X = CH, Z = t-Bu, right). (c) Electrostatic potential maps of the interior surfaces of (left) B and (right) C obtained by DFT calculations at the B3LYP/631G

• -Bu). a) Chemical structure of β-D-glucopyranose and the solid-state structure of its complexes with macrocycle B (X = CH). b) Schematic view of tetralactam B encapsulating glucose (R = O) or glucosammonium (R = NH2+) with stabilizing secondary interactions provided by back-folding of a peripherally

Mechanochemical synthesis of poly(trimethylene carbonate)s: an example of rate acceleration

• Sora Park and
• Jeung Gon Kim

Beilstein J. Org. Chem. 2019, 15, 963–970, doi:10.3762/bjoc.15.93

• added. All reagents were placed in a 10 mL stainless-steel milling jar with three 7 mm diameter stainless-steel balls. The solid-state reaction mixture was placed into a high-speed vibration ball mill. After 30 min of high-speed vibration (30 Hz), 43% conversion was recorded, and PTMC with an Mn of 3930

Halogen bonding and host–guest chemistry between N-alkylammonium resorcinarene halides, diiodoperfluorobutane and neutral guests

• Fangfang Pan,
• Mohadeseh Dashti,
• Michael R. Reynolds,
• Kari Rissanen,
• John F. Trant and
• Ngong Kodiah Beyeh

Beilstein J. Org. Chem. 2019, 15, 947–954, doi:10.3762/bjoc.15.91

• interactions to be used in aqueous or polar environments where HB-based systems are less viable [8][9][10][11][12]. However, we lack the analytical tools to directly examine and determine the precise structure of XB assemblies in solution [13][14][15]. In the solid-state, X-ray diffraction has proven an

• are working in tandem and concertedly to form networks of non-covalent interactions stabilizing the dimeric and capsular structures in the solid state. The inclusion guests affect the geometry of the cavity of the hex-NARBr and cy-NARCl, thus affecting the halogen bonding connection in the final

An anomalous addition of chlorosulfonyl isocyanate to a carbonyl group: the synthesis of ((3aS,7aR,E)-2-ethyl-3-oxo-2,3,3a,4,7,7a-hexahydro-1H-isoindol-1-ylidene)sulfamoyl chloride

• Aytekin Köse,
• Aslı Ünal,
• Ertan Şahin,
• Uğur Bozkaya and
• Yunus Kara

Beilstein J. Org. Chem. 2019, 15, 931–936, doi:10.3762/bjoc.15.89

• changes the stoichiometry. In the solid state, compound 10 is stabilized via effective intramolecular H-bonds. Interactions between C9–H∙∙∙O5 [D∙∙∙A = 3.331(3) Å], C5–H∙∙∙O6 [D∙∙∙A = 3.529(3) Å], C19–H∙∙∙O3 [D∙∙∙A = 3.316(3) Å], C16–H∙∙∙O5 [D∙∙∙A = 3.315(3) Å], and C9–H∙∙∙O4 [D∙∙∙A = 3.313(3) Å

Mechanochemistry of supramolecules

• Anima Bose and
• Prasenjit Mal

Beilstein J. Org. Chem. 2019, 15, 881–900, doi:10.3762/bjoc.15.86

• complexes 30 and 31 upon the addition of Cu(I) tetrafluoroborate (1.5 equiv) and Fe(II) sulfate (1.0 equiv) as shown in Figure 17 [86]. DCL formation was also shown to be possible in the solid-state by grinding or mechanochemical methods by Sanders and co-workers in 2011. They have demonstrated the

• differences in the crystal packing in the solid state. The products 32 were obtained via thermodynamic control (Figure 18) from a dynamic combinatorial library [53][88]. In 2010, Otto and co-workers observed unprecedented product selectivity for the formation of disulfide macromolecules based on mechanical

• -bond formation in supramolecular chemistry which occurs in solution-phase synthesis is almost impossible in solid-state reactions. However, MacGillivray’s group demonstrated several examples of co-crystal formation or supramolecular synthesis in the solid phase through mechano-milling or dry grinding

Coordination chemistry and photoswitching of dinuclear macrocyclic cadmium-, nickel-, and zinc complexes containing azobenzene carboxylato co-ligands

• Jennifer Klose,
• Tobias Severin,
• Peter Hahn,
• Alexander Jeremies,
• Jens Bergmann,
• Daniel Fuhrmann,
• Jan Griebel,
• Bernd Abel and
• Berthold Kersting

Beilstein J. Org. Chem. 2019, 15, 840–851, doi:10.3762/bjoc.15.81

• salts are stable in air both in solution and in the solid state, and are very soluble in a range of common polar organic solvents (CH3CN, EtOH, MeOH). The new compounds gave satisfactory elemental analyses and were characterized by mass spectrometry, spectroscopic methods (IR, UV–vis, 1H and 13C NMR

• azobenzene-carboxylates has been synthesized and characterized in solution and solid state. The diamagnetic Cd(II) and Zn(II) and the paramagnetic Ni(II) complexes were found to be isostructural, with the co-ligands bound via bridging carboxylate functions, a bowl-shaped structure of the supporting [M2L]2

An improved synthesis of adefovir and related analogues

• David J. Jones,
• Eileen M. O’Leary and
• Timothy P. O’Sullivan

Beilstein J. Org. Chem. 2019, 15, 801–810, doi:10.3762/bjoc.15.77

• investigational prodrug strategies is typically measured by derivatising proven therapeutics such as adefovir and comparing the properties of the resulting compounds to the parent substrate [15][19][20][21][22][23][24][25][26][27][28][29][30]. Additionally, the solid state and spectroscopic properties of adefovir

Polyaminoazide mixtures for the synthesis of pH-responsive calixarene nanosponges

• Antonella Di Vincenzo,
• Antonio Palumbo Piccionello,
• Alberto Spinella,
• Delia Chillura Martino,
• Marco Russo and
• Paolo Lo Meo

Beilstein J. Org. Chem. 2019, 15, 633–641, doi:10.3762/bjoc.15.59

• our previous work [22], we observed a reduction of the reaction time needed down to 70 h. The latter finding confirms the idea that increasing the number of azide groups on the structure of the reticulating agent enhances its efficacy. Once again, combined FTIR and solid state CP-MAS 13C NMR confirmed

• and 1031 cm−1, which can be attributed to neither the calixarene scaffold nor the polyaminoazide, whereas fingerprint signals at 1377, 1364, 1189 and 994 cm−1 can be attributed to the calixarene, and the signals at 1289 and 1116 cm−1 can be recognized as due to the linker groups In the solid state 13C

• relevant nanosponges CaNS-I and CaNS-II were similarly subjected to spectroscopic characterization (FTIR, solid-state CP-MAS NMR), whereas their pH-dependent absorption abilities were verified towards typical probe guests such as p-nitroaniline derivatives and commercial dyes. Our results indicate an

Synthesis and fluorescent properties of N(9)-alkylated 2-amino-6-triazolylpurines and 7-deazapurines

• Andrejs Šišuļins,
• Jonas Bucevičius,
• Yu-Ting Tseng,
• Irina Novosjolova,
• Kaspars Traskovskis,
• Ērika Bizdēna,
• Huan-Tsung Chang,
• Sigitas Tumkevičius and
• Māris Turks

Beilstein J. Org. Chem. 2019, 15, 474–489, doi:10.3762/bjoc.15.41

• increases with the increase of solvent polarity. Additionally, X-ray analysis of 2,6-diazidopurine 2'-deoxyribonucleoside revealed the exclusive existence of the azido tautomer in the solid state [41]. The discovered ability of the azido group to be substituted with amines at C(2) position was used for the

Study on the regioselectivity of the N-ethylation reaction of N-benzyl-4-oxo-1,4-dihydroquinoline-3-carboxamide

• Pedro N. Batalha,
• Luana da S. M. Forezi,
• Maria Clara R. Freitas,
• Nathalia M. de C. Tolentino,
• Ednilsom Orestes,
• José Walkimar de M. Carneiro,
• Fernanda da C. S. Boechat and
• Maria Cecília B. V. de Souza

Beilstein J. Org. Chem. 2019, 15, 388–400, doi:10.3762/bjoc.15.35

• structure as shown in Figure 6. As can be seen in Figure 6, attached to the central oxoquinoline ring is an ethyl substituent bonded to N1 and the carboxamide group is attached to C3. The solid-state structure confirms the regioselectivity of the reaction. It is important to note from the crystalline

Computational characterization of enzyme-bound thiamin diphosphate reveals a surprisingly stable tricyclic state: implications for catalysis

• Ferran Planas,
• Michael J. McLeish and
• Fahmi Himo

Beilstein J. Org. Chem. 2019, 15, 145–159, doi:10.3762/bjoc.15.15

• for the APH+ form. However, solid-state NMR using 15N and 13C-labeled ThDP has been used to identify APH+ on pyruvate decarboxylase and the E1 component of the pyruvate dehydrogenase complex [18]. In addition to the plethora of experimental investigations, a number of computational studies have

Systematic synthetic study of four diastereomerically distinct limonene-1,2-diols and their corresponding cyclic carbonates

• Hiroshi Morikawa,
• Jun-ichi Yamaguchi,
• Shun-ichi Sugimura,
• Masato Minamoto,
• Yuuta Gorou,
• Hisatoyo Morinaga and
• Suguru Motokucho

Beilstein J. Org. Chem. 2019, 15, 130–136, doi:10.3762/bjoc.15.13

• reported in our previous study [27]. Of these, 1a has already been synthesised by other groups [10][11] as well as our group. Particularly, Kleij et al. revealed the solid-state structure of 1a via X-ray analysis [11], but the isolation and characterisation of 1d has only been reported by our group. Herein

• coupling constants match well the conformations in Figure 5 although the signal c for 1d unfortunately overlaps with other signals. The structure of 1a is in good agreement with the solid-state structure reported previously [11]. Conformations of the four LMdiols were also considered in the same manner as

• those of LM5CCs by reference to the a and c signals in Figure 4. The coupling constants for the signal a support the structures shown in Figure 5. Indeed, the equatorial position of the isopropenyl group for 2c and 2d in the solid state was confirmed by X-ray diffraction analysis, as reported previously

Fabrication of supramolecular cyclodextrin–fullerene nonwovens by electrospinning

• Hiroaki Yoshida,
• Ken Kikuta and
• Toshiyuki Kida

Beilstein J. Org. Chem. 2019, 15, 89–95, doi:10.3762/bjoc.15.10

• regardless of the incorporation of C60, and the fiber diameter is approximately 3 μm. This may be because all solutions have similar solution properties. To clarify the inner structure of the γ-CD–C60 fibers, solid-state 13C NMR and UV–vis diffuse reflectance spectroscopies were performed. As shown in Figure

•  3d, solid-state 13C NMR clarifies the presence of C60 in the fibers, but does not provide additional information. Solid-state UV–vis reflectance spectroscopy clearly suggests reflectance peaks at 260, 330, and 410 nm. This spectrum is almost the same as those of the γ-CD–C60 complex solutions (Figure

Ruthenium-based olefin metathesis catalysts with monodentate unsymmetrical NHC ligands

• Veronica Paradiso,
• Chiara Costabile and
• Fabia Grisi

Beilstein J. Org. Chem. 2018, 14, 3122–3149, doi:10.3762/bjoc.14.292

• and 25b this orientation was observed also in the solid state. Some metathesis reactions performed in this study with 24b and 25b in comparison to GII-SIMes and HGII-SIMes are summarized in Table 1. In the model RCM reaction of N,N-diallyl-p-toluenesulfonamide (26, Table 1, entry 1), catalysts 24a and

• methyl (41), octyl (42) or cyclohexyl (43, Figure 11) [25]. For all of the complexes, two rotamers were observed in solution, and the most abundant species was identified as the isomer with the indenylidene moiety located under the mesityl group. Solid-state structures of the complexes showed

• ruthenium center was detected in the species 118 by NMR spectroscopy. Evidence for coordination of the amino arm in solution and in the solid state was observed in its derived monopyridine adduct 119 (Figure 22). Complex 118 was found less active than GII-SIMes and GII-IMes in model RCM of 7 and ROMP of 16

The activity of indenylidene derivatives in olefin metathesis catalysts

• Maria Voccia,
• Steven P. Nolan,
• Luigi Cavallo and
• Albert Poater

Beilstein J. Org. Chem. 2018, 14, 2956–2963, doi:10.3762/bjoc.14.275

• generate and/or describe the activity in olefin metathesis of the new indenylidene derivatives. The phenyl substituent of the indenylidene is perpendicular to the indenyl moiety in the solid-state structure [34], as Nolan and co-workers first described in 1999 [35]. For complexes 3–6, where the phenyl ring

1,8-Bis(dimethylamino)naphthyl-2-ketimines: Inside vs outside protonation

• A. S. Antonov,
• A. F. Pozharskii,
• P. M. Tolstoy,
• A. Filarowski and
• O. V. Khoroshilova

Beilstein J. Org. Chem. 2018, 14, 2940–2948, doi:10.3762/bjoc.14.273

• -arylketimines of 1,8-bis(dimethylamonio)naphthalene with a different number of methoxy groups in an aromatic substituent were investigated in solution by NMR (acetone, DMSO, MeCN), in solid state by X-ray analysis and in the gas phase by DFT calculations. Both mono- and diprotonated species were considered. It

• for 4a, while the E-form is more stable for 5a–7a. Indeed, the X-ray analysis shows that compound 6a in the solid state exists in the E-form stabilised by the N−H···O intramolecular hydrogen bond (IHB) with an ortho-OMe group (Figure 2a), while compound 4a, as it was revealed in our previous work [7

• lowest in energy for the imines 4, 6, 7 (Figure 5). In the solid state, no proton transfer to the imino group was observed: compounds 4a·HClO4 and 6b·EtOH crystallise in forms protonated at the proton sponge moiety (Figure 6). We expected that the proton transfer to the C=N group will force the nearest

Non-native autoinducer analogs capable of modulating the SdiA quorum sensing receptor in Salmonella enterica serovar Typhimurium

• Matthew J. Styles and
• Helen E. Blackwell

Beilstein J. Org. Chem. 2018, 14, 2651–2664, doi:10.3762/bjoc.14.243

• ) [21][22]. C) The solid-state structure of the SdiA homodimer (PDB 4Y15; monomers shown in green and grey) bound to OOHL (cyan) [22]. D) Selected residues surrounding OOHL (cyan) in the SdiA ligand binding pocket (from PDB 4Y15 [22]): hydrogen bond acceptors/donors (orange), hydrophobic residues (grey

Synthesis of aryl sulfides via radical–radical cross coupling of electron-rich arenes using visible light photoredox catalysis

• Amrita Das,
• Mitasree Maity,
• Simon Malcherek,
• Burkhard König and
• Julia Rehbein

Beilstein J. Org. Chem. 2018, 14, 2520–2528, doi:10.3762/bjoc.14.228

• the limit of the scope of the method. The substrate scope is shown in Scheme 3. The structures of compounds 3a, 3d, 3e and 3i in the solid state were determined by X-ray structure analysis (Figure 2). We performed various control experiments to support the proposed reaction mechanism, which is shown