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

• distances of ~3.52 Å and 3.46 Å. Pentacene 3d crystallizes in the space group P21/n with four molecules in each unit cell (Figure 8), and the thienyl and trialkylsilyl groups show disorder in the structure. With a twist angle of ~90°, the thienyl unit is essentially perpendicular to the pentacene skeleton

Synthesis of the first examples of iminosugar clusters based on cyclopeptoid cores

• Mathieu L. Lepage,
• Alessandra Meli,
• Anne Bodlenner,
• Céline Tarnus,
• Francesco De Riccardis,
• Irene Izzo and
• Philippe Compain

Beilstein J. Org. Chem. 2014, 10, 1406–1412, doi:10.3762/bjoc.10.144

• storage disorder [8][9]. In 2013, the first description of a multivalent effect for correcting protein folding defects in cells was reported with trivalent DNJ clusters [10]. These compounds were found to overcome the processing defect of the mutant CFTR protein involved in cystic fibrosis, and to be up

Novel indolin-2-one-substituted methanofullerenes bearing long n-alkyl chains: synthesis and application in bulk-heterojunction solar cells

• Irina P. Romanova,
• Andrei V. Bogdanov,
• Inessa A. Izdelieva,
• Vasily A. Trukhanov,
• Gulnara R. Shaikhutdinova,
• Dmitry G. Yakhvarov,
• Shamil K. Latypov,
• Vladimir F. Mironov,
• Vladimir A. Dyakov,
• Ilya V. Golovnin,
• Dmitry Yu. Paraschuk and
• Oleg G. Sinyashin

Beilstein J. Org. Chem. 2014, 10, 1121–1128, doi:10.3762/bjoc.10.111

• features at 550 and 600 nm indicating the lowest content of the P3HT crystalline phase. This was assigned to disorder in the P3HT crystalline phase induced by the PCBM molecules [18]. Thermal annealing of the P3HT/PCBM blend increases the content of the P3HT crystalline phase (the black curve in Figure 5

Carbenoid-mediated nucleophilic “hydrolysis” of 2-(dichloromethylidene)-1,1,3,3-tetramethylindane with DMSO participation, affording access to one-sidedly overcrowded ketone and bromoalkene descendants^§

• Rudolf Knorr,
• Thomas Menke,
• Johannes Freudenreich and
• Claudio Pires

Beilstein J. Org. Chem. 2014, 10, 307–315, doi:10.3762/bjoc.10.28

• )-1,1,3,3-tetramethylindane (6) as the only product (97% yield). (ii) In X-ray diffraction analyses [4][5][6][7][8][9], the 1,1,3,3-tetramethylindan-2-ylidene parts turned out to be rather rigid, except for an occasional folding along the C-1/C-3 axis, and they did not exhibit the structural disorder

The difluoromethylene (CF₂) group in aliphatic chains: Synthesis and conformational preference of palmitic acids and nonadecane containing CF₂ groups

• Yi Wang,
• Ricardo Callejo,
• Alexandra M. Z. Slawin and
• David O’Hagan

Beilstein J. Org. Chem. 2014, 10, 18–25, doi:10.3762/bjoc.10.4

• -crystalline nature of 6b presumably arises due to chain disorder from linear 1,3-repulsions between the fluorines, so the preferred conformation of this motif could not be determined in this study. The melting point of palmitic acid 6c (89.9 °C) was notable in that it was significantly higher than that of the

• conformation (Figure 8). Also repulsive through space 1,4-F···F interactions will be disfavoured if the chain undergoes gauche conformational disorder. These contributing factors suggest that the 1,4-di-CF2 motif (R–CF2CH2CH2CF2–R) will be useful for adding conformational stability to aliphatic chains. The CF2

Stereoselectively fluorinated N-heterocycles: a brief survey

• Xiang-Guo Hu and
• Luke Hunter

Beilstein J. Org. Chem. 2013, 9, 2696–2708, doi:10.3762/bjoc.9.306

• [21]. For example, O’Hagan and co-workers investigated the pyrrolidine-containing molecules 9 and 10 (Figure 3) as ligands of G-quadruplex DNA [22]. The non-fluorinated ligand 9 had some conformational disorder because the pyrrolidine rings were able to interconvert between exo and endo puckers. In

• rigidifying power of a fluorine substituent is strongly dependent on the other groups present. The non-fluorinated azepane 21 was found to exhibit extensive conformational disorder, and this was attributed to competing preferences for the OBn/N3 substituents to adopt pseudoequatorial positions and for the

• preferred over the equatorial conformation (9.2 kcal/mol) because of two stabilising C–F…N+ interactions. An X-ray structure of 24 was also obtained (Figure 7), and it revealed a geometry consistent with the calculated minimum-energy structure, with no evidence of disorder. So far in this review, we have

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

Structures of the reaction products of the AZADO radical with TCNQF₄ or thiourea

• Hideto Suzuki,
• Yuta Kawahara,
• Hiroki Akutsu,
• Jun-ichi Yamada and
• Shin’ichi Nakatsuji

Beilstein J. Org. Chem. 2013, 9, 1487–1491, doi:10.3762/bjoc.9.169

• radical molecules within the channels [9], although the single crystal data at low temperatures are not available yet and the distinct feature of the disorder is not clarified at present. Quite similar λmax-values of the inclusion compound 6 are found to those of thiourea (4) in their UV–vis absorption

A simple, enaminone-based approach to some bicyclic pyridazinium tetrafluoroborates

• František Josefík,
• Markéta Svobodová,
• Valerio Bertolasi and
• Petr Šimůnek

Beilstein J. Org. Chem. 2013, 9, 1463–1471, doi:10.3762/bjoc.9.166

• others are given in Supporting Information File 1. Almost all the structures display some disorder. Structures 5d, 5f, 5j and 5l show disorder in the C3–C7,N3 six-membered rings and the C5H2 moieties were refined over two sites. All the BF4− anions exhibit high temperature factors; in 5d and 5l the

Amyloid-β probes: Review of structure–activity and brain-kinetics relationships

• Todd J. Eckroat,
• Abdelrahman S. Mayhoub and
• Sylvie Garneau-Tsodikova

Beilstein J. Org. Chem. 2013, 9, 1012–1044, doi:10.3762/bjoc.9.116

• ; radioactive probes; Introduction Alzheimer’s disease (AD) is a progressive neurodegenerative disorder of the central nervous system currently affecting ~5.4 million Americans, a number that could increase to 11–16 million by the year 2050. In the United States, AD represents the 6th leading cause of death

Recent progress in the discovery of small molecules for the treatment of amyotrophic lateral sclerosis (ALS)

• Allison S. Limpert,
• Margrith E. Mattmann and
• Nicholas D. P. Cosford

Beilstein J. Org. Chem. 2013, 9, 717–732, doi:10.3762/bjoc.9.82

• neurodegenerative disorder with few therapeutic options. While several gene mutations have been implicated in ALS, the exact cause of neuronal dysfunction is unknown and motor neurons of affected individuals display numerous cellular abnormalities. Ongoing efforts to develop novel ALS treatments involve the

• lateral sclerosis (ALS), also known as Lou Gehrig’s disease, is a progressive neurodegenerative disease that leads to the dysfunction and death of motor neurons in both the motor cortex and spinal cord. This adult-onset disorder leads to paralysis and eventual death, most commonly by asphyxiation

• (sALS) and 10% of all cases characterized as familial (fALS) [4]. Several gene mutations have been identified that contribute to this disorder with 20% of fALS cases being linked to mutations in the copper/zinc (Cu-Zn) superoxide dismutase 1 (SOD1) gene [4]. Many cellular pathologies have been

Spin state switching in iron coordination compounds

• Philipp Gütlich,
• Ana B. Gaspar and
• Yann Garcia

Beilstein J. Org. Chem. 2013, 9, 342–391, doi:10.3762/bjoc.9.39

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

• ]. A crystalline inclusion complex (TRIMEA)2·1 was isolated and shown by X-ray analysis to contain a novel capsule formed by head-to-head contact of the secondary rims of two TRIMEA molecules [5]. The encapsulated fenitrothion molecule showed minor disorder in the form of two rotamers (with respect to

• arrangement and showing severe guest disorder, which was eventually resolved and successfully modelled. In addition, the results of a kinetic study of the hydrolytic degradation of 1 in the presence of DIMEB are reported and compared with those observed for the other CDs under the same reaction conditions

• appear similar, there are obvious differences in the conformations of the two independent host molecules, and in particular, the images of the respective guest molecules are very different, as described further below. This is due to an unusually high level of guest disorder occurring in this complex

A new family of four-ring bent-core nematic liquid crystals with highly polar transverse and end groups

• Kalpana Upadhyaya,
• Venkatesh Gude,
• Golam Mohiuddin and
• Rao V. S. Nandiraju

Beilstein J. Org. Chem. 2013, 9, 26–35, doi:10.3762/bjoc.9.4

• azobenzene or salicylideneimine or phenylbenzoate unit in one of the arms of the bent molecule by a polar cyanobiphenyl moiety lends stiffness to the molecule with a strong dipole moment in the lateral direction. The realization of such a molecular architecture leads to a reduction in rotational disorder as

• a lateral polar substituent [21][22][54][55][56][57] leads to the reduction of the rotational disorder of the molecules around their long axes to promote nematic phases. However, for short-chain members of a homologous series (n-butyl to n-hexyl units), the microsegregation of incompatible aromatic

The preferred conformation of erythro- and threo-1,2-difluorocyclododecanes

• Yi Wang,
• Peer Kirsch,
• Tomas Lebl,
• Alexandra M. Z. Slawin and
• David O'Hagan

Beilstein J. Org. Chem. 2012, 8, 1271–1278, doi:10.3762/bjoc.8.143

• to a high level of disorder, but the diffraction data was used as the basis of a further computational analysis, and the structure in Figure 1 emerged as their consensus structure [5][6]. The structure is tensioned by transannular interactions in which there are four endo hydrogens, one on each edge

Liquid-crystalline heterodimesogens and ABA-heterotrimesogens comprising a bent 3,5-diphenyl-1,2,4-oxadiazole central unit

• Govindaswamy Shanker,
• Marko Prehm and
• Carsten Tschierske

Beilstein J. Org. Chem. 2012, 8, 472–485, doi:10.3762/bjoc.8.54

• ). Considering the tilt, a calculated d-value of dcal = 4.8 nm would be expected according to dcal = Lmol cos β for the molecule in the most stretched conformation and a reduction to the experimental value of d = 4.4 nm is easily possible by conformational disorder. Hence, it is in line with a monolayer

Liquid-crystalline nanoparticles: Hybrid design and mesophase structures

• Gareth L. Nealon,
• Romain Greget,
• Cristina Dominguez,
• Zsuzsanna T. Nagy,
• Daniel Guillon,
• Jean-Louis Gallani and
• Bertrand Donnio

Beilstein J. Org. Chem. 2012, 8, 349–370, doi:10.3762/bjoc.8.39

• liquidlike nature of the organic sublayer was confirmed by X-ray experiments, and the lack of observable birefringence in the sample was taken as further evidence of the orientational disorder of the molecules inside the organic layer of the smectic materials. The role of subtle changes to the mesogenic

• layer [64]. These latter results were mirrored for the structurally similar single-chained ligand 9 (Figure 8), which displayed an increase in the interparticle distance within the smectic layers upon an increase in the length of the primary grafting layer. Once again, the orientational disorder of the

Improved syntheses of high hole mobility phthalocyanines: A case of steric assistance in the cyclo-oligomerisation of phthalonitriles

• Daniel J. Tate,
• Rémi Anémian,
• Richard J. Bushby,
• Suwat Nanan,
• Stuart L. Warriner and
• and Benjamin J. Whitaker

Beilstein J. Org. Chem. 2012, 8, 120–128, doi:10.3762/bjoc.8.14

• high is not entirely easy to understand. Mobilities in liquid crystals are usually intermediate between those measured in crystalline and amorphous organic solids, and the mobility is primarily related to the degree of positional [40][41][42][43][44] or charge [45][46] disorder within the system. In

Fluorescent hexaaryl- and hexa-heteroaryl[3]radialenes: Synthesis, structures, and properties

• Antonio Avellaneda,
• Courtney A. Hollis,
• Xin He and
• Christopher J. Sumby

Beilstein J. Org. Chem. 2012, 8, 71–80, doi:10.3762/bjoc.8.7

• space group P21/c and the asymmetric unit contains one molecule of the radialene ligand and an acetonitrile solvate molecule (Figure 2). The small crystals were weakly diffracting but the structure refined to R1 6.82% with no significant disorder problems. As expected, the [3]radialene core is planar

On the control of secondary carbanion structure utilising ligand effects during directed metallation

• Andrew E. H. Wheatley,
• Jonathan Clayden,
• Ian H. Hillier,
• Alison Campbell Smith,
• Mark A. Vincent,
• Laurence J. Taylor and
• Joanna Haywood

Beilstein J. Org. Chem. 2012, 8, 50–60, doi:10.3762/bjoc.8.5

• disorder that limited the analysis of the structure of 3-Lil·PMDTA by preventing the anisotropic refinement of both the aromatic ring and the deprotonated alkyl chain [23]. In fact, the direct observation of H8 by Fourier difference synthesis [29][30] and the anisotropic refinement of this atom allows an

• aromatic carbon centre para to it, the situation for secondary carbanionic 6-Lil·PMDTA is different. This could not be ascertained for previously reported 3-Lil·PMDTA [23], where crystallographic disorder meant that both the arene–(α-C) interaction and bonds within the aromatic ring were constrained. In

Planar-bilayer activities of linear oligoester bolaamphiphiles

• Jonathan K. W. Chui,
• Thomas M. Fyles and
• Horace Luong

Beilstein J. Org. Chem. 2011, 7, 1562–1569, doi:10.3762/bjoc.7.184

• is normally stable to potentials exceeding 400 mV and does not show any detectible phase transitions [28][29]. It is conceivable that our introduction of “impurities” creates local disorder akin to domain separation at the melting transition and that fluctuations at the domain boundaries would give

Meta-metallation of N,N-dimethylaniline: Contrasting direct sodium-mediated zincation with indirect sodiation-dialkylzinc co-complexation

• David R. Armstrong,
• Liam Balloch,
• Eva Hevia,
• Alan R. Kennedy,
• Robert E. Mulvey,
• Charles T. O'Hara and
• Stuart D. Robertson

Beilstein J. Org. Chem. 2011, 7, 1234–1248, doi:10.3762/bjoc.7.144

• = 0.969 and −0.682 e·Å−3. Disorder in the TMEDA groups was treated as being over two sites, appropriate restraints on atom-atom distances and temperature factors in these groups were applied. Crystal data for 6: C27H53N4NaZn, M = 522.09, orthorhombic, Pbca, a = 16.1371(5), b = 17.2078(5), c = 21.6306(5) Å

• ]+ calcd for C8H9I2N, 372.8; found, 373.8. Molecular structure of 2 with selective atom labelling. Hydrogen atoms and minor disorder components are omitted for clarity [20]. Molecular structure of 3 with selective atom labelling and thermal ellipsoids drawn at the 50% probability level. Hydrogen atoms are

Intraannular photoreactions in pseudo-geminally substituted [2.2]paracyclophanes

• Henning Hopf,
• Vitaly Raev and
• Peter G. Jones

Beilstein J. Org. Chem. 2011, 7, 658–667, doi:10.3762/bjoc.7.78

• four-membered rings were refined freely but with C–H distance restraints. For (Z,Z)-22 and 23, which crystallize in non-centrosymmetric space groups, anomalous scattering was negligible and Friedel opposite reflections were therefore merged. For 24, the atoms C23–26 show a slight (9%) disorder. The

• disorder model was refined using a system of similarity restraints. Dimensions of the minor disorder component should be interpreted with great caution. Crystallographic data have been deposited with the Cambridge Crystallographic Data Centre as supplementary publications no. CCDC-797335 (13), -797336 (15

An overview of the key routes to the best selling 5-membered ring heterocyclic pharmaceuticals

• Marcus Baumann,
• Ian R. Baxendale,
• Steven V. Ley and
• Nikzad Nikbin

Beilstein J. Org. Chem. 2011, 7, 442–495, doi:10.3762/bjoc.7.57

Fluorometric recognition of both dihydrogen phosphate and iodide by a new flexible anthracene linked benzimidazolium-based receptor

• Kumaresh Ghosh and
• Debasis Kar

Beilstein J. Org. Chem. 2011, 7, 254–264, doi:10.3762/bjoc.7.34

• such as neurological activity and thyroid function. The iodide content of urine and milk is often required to provide information for nutritional, metabolic, and epidemiological studies of thyroid disorder [40]. In relation to this, very few reports on iodide recognition are known in the literature [41