A new class of organogelators based on triphenylmethyl derivatives of primary alcohols: hydrophobic interactions alone can mediate gelation

• Wangkhem P. Singh and
• Rajkumar S. Singh

Beilstein J. Org. Chem. 2017, 13, 138–149, doi:10.3762/bjoc.13.17

• ][24]. Similar is the case for π-stacking interaction (seen in naphthalene, anthracene, pyrene, perylene, etc.) which has been mostly used in combination with other types of secondary interactions in the discovery of many gelators [25][26]. This holds true for many other non-covalent interactions as

• geometry (unlike the planar geometry of say anthracene, pyrene, etc.), π–π stacking will be favoured only between benzene units of different trityl groups. A small library of triphenylmethyl derivatives was synthesized from the corresponding primary alcohols employing a single step reaction and detailed

• interactions between the alkyl chains and the triphenylmethyl moieties. Compared to other planar aromatic molecules (such as naphthalene, anthracene, perylene, etc.), the triphenylmethyl moiety as a whole exhibits a non-planar geometry, hence π-stacking interaction between triphenylmethyl moieties may not be

Hydroxy-functionalized hyper-cross-linked ultra-microporous organic polymers for selective CO₂ capture at room temperature

• Partha Samanta,
• Priyanshu Chandra and
• Sujit K. Ghosh

Beilstein J. Org. Chem. 2016, 12, 1981–1986, doi:10.3762/bjoc.12.185

• -(hydroxymethyl)anthracene, respectively (Figure 1). HCP-91 and HCP-94 have been synthesized by using a Friedel–Crafts alkylation reaction. The thus obtained as-synthesized compounds were washed repeatedly with dimethylformamide (DMF), methanol, water, chloroform, dichloromethane and tetrahydrofuran (THF) to

Cross-linked cyclodextrin-based material for treatment of metals and organic substances present in industrial discharge waters

• Élise Euvrard,
• Nadia Morin-Crini,
• Coline Druart,
• Justine Bugnet,
• Bernard Martel,
• Cesare Cosentino,
• Virginie Moutarlier and
• Grégorio Crini

Beilstein J. Org. Chem. 2016, 12, 1826–1838, doi:10.3762/bjoc.12.172

• PAHs: naphthalene (NAP), acenaphthene (ACE), acenaphthylene (ACY), fluorene (FLU), phenanthrene (PHE), anthracene (ANT), fluoranthene (FLT) and pyrene (PYR); eight heavy PAHs: benz[a]anthracene (BaANT), chrysene (CHY), benzo[b]fluoranthene (BbFLT), benzo[k]fluoranthene (BkFLT), benzo[a]pyrene (BaPYR

• ), dibenz[a,h]anthracene (dBahANT), indeno[1,2,3-cd]pyrene (IcdPYR) and benzo[g,h,i]perylene (BghiPL); three APs: 4-nonylphenol (4NP, CAS no. 84852-15-3), 4-n-nonylphenol (4nNP, CAS no. 104-40-5) and 4-tert-octylphenol (4tOP, CAS no. 140-66-9). Calcium chloride and sodium bicarbonate were purchased from

Rearrangements of organic peroxides and related processes

• Ivan A. Yaremenko,
• Vera A. Vil’,
• Dmitry V. Demchuk and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162

Ring-whizzing in polyene-PtL₂ complexes revisited

• Oluwakemi A. Oloba-Whenu,
• Thomas A. Albright and
• Chirine Soubra-Ghaoui

Beilstein J. Org. Chem. 2016, 12, 1410–1420, doi:10.3762/bjoc.12.135

• complexes [64][65][66][67] are akin to 45. Our calculated barrier of 14.7 kcal/mol via 47 seems a bit too low. The measured barrier in two Pd(tmeda) complexes was 21.4 and 21.6 kcal/mol [66]. No signs of fluxionality was found in a substituted phenalenium–Pt(PPh3)2+ complex [67]. Naphthalene and anthracene

• energy to attain 50 in C10F8–Pt(dpe) was computed to be 13.7 kcal/mol; in C10H8–Pt(dpe) the barrier was 14.8 kcal/mol. This is in line with an NMR derived barrier of about 15 kcal/mol for C10H8NiL2 [74] and 15–20 kcal/mol for anthracene–Ni(PR3)2 [69][70]. Oprunenko and Gloriozov [75] have calculated the

• this point theory and experiment appear to be in agreement for the NiL2 and PtL2 cases. But the story does not end here. Experimentally there is a low energy process that converts, 48, to the equivalent η2 complex where the ML2 group is coordinated to C(3) and C(4). This is also the case for anthracene

Scope and mechanism of the highly stereoselective metal-mediated domino aldol reactions of enolates with aldehydes

• M. Emin Cinar,
• Bernward Engelen,
• Martin Panthöfer,
• Hans-Jörg Deiseroth,
• Jens Schlirf and
• Michael Schmittel

Beilstein J. Org. Chem. 2016, 12, 813–824, doi:10.3762/bjoc.12.80

• combination with different metals (Table 5). All aromatic aldehydes, even those containing strongly coordinating substituents such as the dimethylamino group, are accepted in this transformation. With anthracene-9-carbaldehyde (3f), however, the yields drastically decreased, most likely due to steric

• hindrance. Although benzaldehyde (3a) was not used, product 5a appeared in the reaction of anthracene-9-carbaldehyde (3f) with Al and Zr metals, a finding that requires an explanation (vide infra). The NMR investigations suggest the same relative configuration of 5b−j as in 5a since coupling constants, the

Self and directed assembly: people and molecules

• Tony D. James

Beilstein J. Org. Chem. 2016, 12, 391–405, doi:10.3762/bjoc.12.42

• enantiomers of tartaric acid and also bound bind strongly with other sugar acids [61] (Figure 9). While, we were very happy with these results, we realised that the system could be improved by changing the fluorophore from binol, to a much better fluorophore such as anthracene. Therefore, we combined the

• ] + [R] = 5.0 × 10−6 mol dm−3; λem at 358 nm. Reproduced with permission from [61]. Copyright 2004 John Wiley and Sons. Chiral discriminating sensor (relative stereochemistry shown) constructed using a good fluorophore (anthracene). Fluorescence emission intensity-pH profile of: (a) Sensor 15: 1.0 × 10−6

Facile synthesis of 4H-chromene derivatives via base-mediated annulation of ortho-hydroxychalcones and 2-bromoallyl sulfones

• Srinivas Thadkapally,
• Athira C. Kunjachan and
• Rajeev S. Menon

Beilstein J. Org. Chem. 2016, 12, 16–21, doi:10.3762/bjoc.12.3

• . Polycyclic aromatic hydrocarbon frameworks (naphthalene and anthracene rings) as well as a representative heterocyclic ring (furan) may be incorporated into the 4H-chromene skeleton product by using chalcones (7c, 7d, and 7e, respectively) functionalized with these moieties. Disappointingly, attempts to

Smart molecules for imaging, sensing and health (SMITH)

• Bradley D. Smith

Beilstein J. Org. Chem. 2015, 11, 2540–2548, doi:10.3762/bjoc.11.274

• a remarkable self-assembly process that we call Synthavidin (synthetic avidin). A simple example is illustrated in Scheme 5 [44]. A water soluble tetralactam macrocycle with anthracene sidewalls is threaded by squaraine dyes that are flanked by long PEG chains to give highly stable complexes with

• and there is coplanar stacking of the squaraine aromatic surfaces with the anthracene sidewalls of the macrocycle. We are beginning to use Synthavidin technology as a self-assembly platform to rapidly fabricate libraries of targeted multivalent probes for fluorescence imaging of over-expressed

Syntheses of 2-substituted 1-amino-4-bromoanthraquinones (bromaminic acid analogues) – precursors for dyes and drugs

• Enas M. Malik,
• Younis Baqi and
• Christa E. Müller

Beilstein J. Org. Chem. 2015, 11, 2326–2333, doi:10.3762/bjoc.11.253

• ; Introduction Anthraquinones (AQs, anthracene-9,10-diones) represent an important class of organic compounds. They may be produced synthetically, but many derivatives can also be found in nature, e.g., in medicinal plants, as well as in bacteria, fungi and some insects [1][2][3][4][5][6]. Both, natural and

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

• that forms complexes with Ni(0), Cu(I), Co(0) and also with Ag+ cations. Glaser–Eglinton coupling: Whitlock and Cloninger [88] have reported the synthesis of cyclophane 43 using the Glaser–Eginton coupling reaction. In this regard, compound 40 was treated with 9,10-bis(chloromethyl)anthracene (41

• –face interaction between the face of the anthracene bridge present in the cyclophane molecule and the edge of the host molecule. Bukownik and Wilcox [89] have synthesized macrocyclic C-glycosyl compounds, and obtained the chiral and water-soluble cyclophane 46. They reported on the use of its

• syntheses of 100 molecules by using the McMurry reaction followed by hydrogenation. Pei and co-workers [120] have synthesized anthracene-based π-conjugated strained cyclophane 101 by using an intramolecular McMurry reaction. The combination of unsaturated linkages in these molecules might create a twisted

Single-molecule conductance of a chemically modified, π-extended tetrathiafulvalene and its charge-transfer complex with F₄TCNQ

• Raúl García,
• M. Ángeles Herranz,
• Edmund Leary,
• M. Teresa González,
• Gabino Rubio Bollinger,
• Marius Bürkle,
• Linda A. Zotti,
• Yoshihiro Asai,
• Fabian Pauly,
• Juan Carlos Cuevas,
• Nicolás Agraït and
• Nazario Martín

Beilstein J. Org. Chem. 2015, 11, 1068–1078, doi:10.3762/bjoc.11.120

• functionalized with two (p-acetylthio)phenylethynyl substituents at positions 2 and 6 of the anthracene central core. We then describe single-molecule conductance measurements on this new derivative, along with measurements of the charge-transfer complex formed with F4TCNQ. Finally, we present theoretical

• (i.e., thiol to thiol). We calculate an S–S distance of 2.4 nm for the CT complex (substituting the dihydroanthracene core of compound 5 for anthracene). We estimate the amount of gold retraction to be 0.5 nm, which then gives a real Au–Au separation of 1.64 ± 0.30 nm for the mean breaking distance of

• difference in geometries. Thus, it is more than plausible that the molecule retains its cationic state in the junction. We further point out that in several recent studies, a very similar conductance was found for a molecule that is structurally similar and contains only the anthracene central group. In a

Properties of PTFE tape as a semipermeable membrane in fluorous reactions

• Brendon A. Parsons,
• Olivia Lin Smith,
• Myeong Chae and
• Veljko Dragojlovic

Beilstein J. Org. Chem. 2015, 11, 980–993, doi:10.3762/bjoc.11.110

• through PTFE tape, even if though they do not wet the tape by adsorption [32]. Finally, when peroxide in tert-butanol/water (2:1) was the oxidant and 9,10-bis(phenylethynyl)anthracene the acceptor, solvent-assisted diffusion of dimethyl phthalate was visualized (Figure 14). One can observe bright green

• -butanol–aqueous peroxide solution in the vial after (e) 5 min, (f) 10 min, (g) 15 min, (h) 20 min. Diffusion of dimethyl phthalate assisted by tert-butanol through PTFE was visualized in a chemiluminescence reaction in which 9,10-bis(phenylethynyl)anthracene and an oxalate ester in dimethylphthalate

First principle investigation of the linker length effects on the thermodynamics of divalent pseudorotaxanes

• Andreas J. Achazi,
• Doreen Mollenhauer and
• Beate Paulus

Beilstein J. Org. Chem. 2015, 11, 687–692, doi:10.3762/bjoc.11.78

• strongly related to the experimentally investigated systems of Jiang et al. [16]. The only difference is that 1,4-diazanaphthalene groups of the host molecule are replaced by phenyl groups and the side chains of the anthracene bridge in the divalent host are neglected. In addition to the electronic

• /acetonitrile. The influence of the counter ion PF6− onto the Gibbs energy of association is taken into account explicitly. The divalent host molecules consist of two crown-8 ethers that are linked by an anthracene bridge. For the divalent guest molecule different flexible linkers, namely –O(CH2)2O– (n0), –O

• dispersive interaction of the linking unit (two phenyl rings and the linker), which in case of the n0 guest fits perfectly on top of the anthracene linker of the DiC8 host. The distance between the linker of the host and the linker of the n0 guest is around 3.7 Å, quite close to an ideal distance for the π–π

Articulated rods – a novel class of molecular rods based on oligospiroketals (OSK)

• Pablo Wessig,
• Roswitha Merkel and
• Peter Müller

Beilstein J. Org. Chem. 2015, 11, 74–84, doi:10.3762/bjoc.11.11

• [4 + 4] photocycloaddition of anthracene derivatives. At first we pursued a sequential approach by introducing the pyrene-1-ylacetyl and the cinnamoyl moieties in a two-step sequence in 4-hydroxypiperidine with subsequent oxidation to give piperidin-4-ones 27a,b. An appropriate anthracene derivative

• was not accessible by this approach due to the high sensitivity of the anthracene moiety against various oxidation conditions. For the construction of articulated rods we also prepared alkyne 28 by deprotection of diol 6. In addition we used the literature known building blocks 27c (see below the

• case of anthracene. In addition a convergent approach in which the terminal functionalities are introduced as late as possible in the synthesis (ideally in the last step) would be an advantage. We achieved this goal starting with the ω,ω’-dielectrophilic AR 32c. Thus, treatment with different potassium

Aryl substitution of pentacenes

• Andreas R. Waterloo,
• Anna-Chiara Sale,
• Dan Lehnherr,
• Frank Hampel and
• Rik R. Tykwinski

Beilstein J. Org. Chem. 2014, 10, 1692–1705, doi:10.3762/bjoc.10.178

• motif also places the anthracene moieties in a face-to-face packing 1D slipped stack arrangement, although the interplanar distance of ~3.61 Å is sizable. The aromatic pentacene cores pack in a face-to-face 2D bricklayer arrangement, with approximately two pentacene rings overlapping and interplanar

Nonanebis(peroxoic acid): a stable peracid for oxidative bromination of aminoanthracene-9,10-dione

• Vilas Venunath Patil and
• Ganapati Subray Shankarling

Beilstein J. Org. Chem. 2014, 10, 921–928, doi:10.3762/bjoc.10.90

• acid and oxidative bromination of amino-anthracene-9,10-dione have not been reported in literature. This oxidation strategy allowed us to brominate various amino anthraquinone derivatives in good yield and at ambient temperature. Result and Discussion The oxidant, nonanebis(peroxoic acid) was

• 9 and 10). The other oxidants (Table 3, entries 4, 5, 11, 12) showed moderate to poor conversion. The optimized conditions have a broad substrate scope which was investigated by examining various amino substituted derivatives of anthracene-9,10-dione. In most cases, under standard conditions, the

Metal and metal-free photocatalysts: mechanistic approach and application as photoinitiators of photopolymerization

• Jacques Lalevée,
• Sofia Telitel,
• Pu Xiao,
• Marc Lepeltier,
• Frédéric Dumur,
• Fabrice Morlet-Savary,
• Didier Gigmes and
• Jean-Pierre Fouassier

Beilstein J. Org. Chem. 2014, 10, 863–876, doi:10.3762/bjoc.10.83

• dye Vi [61][62] or an anthracene derivative (e.g. bis[(triisopropylsilyl)ethynyl]anthracene) [54][55] as PIC, Ph2I+ as eA and TTMSS as Add (see the simplified Scheme 9 based on Scheme 6). Using violanthrone-79/Ph2I+/TTMSS allowed, for the first time, the formation of an initiating cationic species

• under a red laser line exposure at 635 nm. This result was very important as cationic polymerization in these irradiation conditions was not possible previously. Changing Vi or the anthracene derivative for a hydrocarbon (e.g. pyrene, naphthacene, pentacene) allows a tunable absorption of the system

Topochemical control of the photodimerization of aromatic compounds by γ-cyclodextrin thioethers in aqueous solution

• Hai Ming Wang and
• Gerhard Wenz

Beilstein J. Org. Chem. 2013, 9, 1858–1866, doi:10.3762/bjoc.9.217

• aromatic guests under controlled, homogenous reaction conditions. The quantum yields for unsubstituted anthracene, acenaphthylene, and coumarin complexed in these γ-CD thioethers were found to be up to 10 times higher than in the non-complexed state. The configuration of the photoproduct reflected the

• -to-head dimer. The degree of complexation of coumarin could be increased by employing the salting out effect. Keywords: acenaphthylene; anthracene; coumarin; cyclodextrins; photodimerization; quantum yield; stereoselectivity; Introduction Photochemical reactions have been considered highly

• complexes with polycyclic aromatics, such as naphthalene, anthracene (ANT), and acenaphthylene (ACE) [25]. In the following we report on the photochemistry of ANT, ACE and coumarin (COU), templated by complexation in several hydrophilic γ-CD thioethers 1–7 (Figure 1 and Figure 2). Special attention will be

Integrating reaction and analysis: investigation of higher-order reactions by cryogenic trapping

• Skrollan Stockinger and
• Oliver Trapp

Beilstein J. Org. Chem. 2013, 9, 1837–1842, doi:10.3762/bjoc.9.214

• presented. The reaction and the analytical separation are combined in a single experiment to investigate the Diels–Alder reaction of benzenediazonium-2-carboxylate as a benzyne precursor with various anthracene derivatives, i.e. anthracene, 9-bromoanthracene, 9-anthracenecarboxaldehyde and 9

• our novel ocRGC setup, we chose the cycloaddition of benzyne with anthracene derivatives in a typical Diels–Alder-reaction (Scheme 1) as a model reaction. This reaction seemed suitable because of the volatility of all reactants and products and the required reaction temperature, which is in an

• , we chose to inject the heat-labile benzenediazonium-2-carboxylate after the anthracene derivative, because we expected that the thermally formed benzyne would be surrounded by the anthracene derivative, and an optimal conversion should occur. Surprisingly, the inverse injection order leads to a

Mechanistic studies on the CAN-mediated intramolecular cyclization of δ-aryl-β-dicarbonyl compounds

• Brian M. Casey,
• Dhandapani V. Sadasivam and
• Robert A. Flowers II

Beilstein J. Org. Chem. 2013, 9, 1472–1479, doi:10.3762/bjoc.9.167

• observation that 3g’ is the only product observed. A similar trend was observed for the 2-naphthyl substrate 1j. The barrier for TS2j”, which would form anthracene-derived product 2j”, is 1.5 kcal/mol higher than TS2j’ and provides a rationale for the selective formation of the phenanthrene-derived product

Thiourea-catalyzed Diels–Alder reaction of a naphthoquinone monoketal dienophile

• Carsten S. Kramer and
• Stefan Bräse

Beilstein J. Org. Chem. 2013, 9, 1414–1418, doi:10.3762/bjoc.9.158

• . Unless stated otherwise, all commercially available compounds (Acros, Fluka, Aldrich) were used as received. Ethyl 4-((tert-butyldimethylsilyl)oxy)-5,8-dimethoxy-2-methyl-10-oxo-4,4a,9a,10-tetrahydro-1H-spiro[anthracene-9,2'-[1,3]dioxolane]-9a-carboxylate (2a): In a small flask dienophile 3 (23.1 mg

Spectroscopic characterization of photoaccumulated radical anions: a litmus test to evaluate the efficiency of photoinduced electron transfer (PET) processes

• Maurizio Fagnoni,
• Stefano Protti,
• Davide Ravelli and
• Angelo Albini

Beilstein J. Org. Chem. 2013, 9, 800–808, doi:10.3762/bjoc.9.91

• solution) in the presence of tertiary amines allowed the accumulation of the corresponding radical anions, up to quantitative yield for polysubstituted benzenes and partially with naphthalene and anthracene derivatives. The condition for such an accumulation was that the donor radical cation underwent

Ring-opening reaction of 2,5-dioctyldithieno[2,3-b:3',2'-d]thiophene in the presence of aryllithium reagents

• Hao Zhong,
• Jianwu Shi,
• Jianxun Kang,
• Shaomin Wang,
• Xinming Liu and
• Hua Wang

Beilstein J. Org. Chem. 2013, 9, 767–774, doi:10.3762/bjoc.9.87

• observed in the case of 2a, 2f and 2g (Table 1, entries 1, 6 and 7). When the bulkiness of aryl groups increased from benzene to anthracene, the yields of ring-opening products decreased from 3a (88%), to 3f (61%) and to 3g (56%). Therefore, the aryllithium reagents with bulky groups, such as

Synthesis of 2,3-dihydronaphtho[2,3-d][1,3]thiazole-4,9-diones and 2,3-dihydroanthra[2,3-d][1,3]thiazole-4,11-diones and novel ring contraction and fusion reaction of 3H-spiro[1,3-thiazole-2,1'-cyclohexanes] into 2,3,4,5-tetrahydro-1H-carbazole-6,11-diones

• Lidia S. Konstantinova,
• Kirill A. Lysov,
• Ljudmila I. Souvorova and
• Oleg A. Rakitin

Beilstein J. Org. Chem. 2013, 9, 577–584, doi:10.3762/bjoc.9.62

• -anthracene-1,4-diones 4 with S2Cl2 and DABCO in chlorobenzene gave the corresponding 2,3-dihydronaphtho[2,3-d][1,3]thiazole-4,9-diones 1 and 2,3-dihydroanthra[2,3-d][1,3]thiazole-4,11-diones 2 by triethylamine addition, in high to moderate yields. The DABCO replacement for N-ethyldiisopropylamine in the

• reaction of anthracene-1,4-diones 4 led unexpectedly to the corresponding 2-thioxo-2,3-dihydroanthra[2,3-d][1,3]thiazole-4,11-diones 10. The reaction of 3H-spiro[1,3-thiazole-2,1'-cyclohexanes] 1d, 2d with Et3N in chlorobenzene under reflux yielded 2,3,4,5-tetrahydro-1H-carbazole-6,11-diones 15, 16, i.e

• ., ring contraction and fusion products. A plausible mechanism was proposed for the formation of the products. Keywords: anthracene-1,4-diones; 1H-carbazole-6,11-diones; fused thiazoles; fusion reaction; heterocycles; naphthoquinones; ring contraction; sulfur–nitrogen; Introduction The 1,4