Fifty years of oxacalix[3]arenes: A review

• Kevin Cottet,
• Paula M. Marcos and
• Peter J. Cragg

Beilstein J. Org. Chem. 2012, 8, 201–226, doi:10.3762/bjoc.8.22

• subtle spectroscopic features and computer models appeared to indicate fullerene binding, structural evidence was to be more compelling. In 1998, Fuji reported the solid-state structure of 3f with C60 as proof of 1:1 binding [76]. Alignment of the oxacalix[3]arene C3 axis with the same symmetry axis of

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

• . Attempts to utilise THF in this last system resulted, instead, in the isolation and characterisation of ortho metallated 3-Lio·THF, the solid-state structure of which revealed a dimeric structure analogous to those seen for 1-Lio·THF and 2-Lio·THF [21]. It was subsequently established that the conversion

• with nitrogen (in PMDTA) and that DGME is a less sterically congesting donor additive than PMDTA, the solid-state structure of 6-Lil·DGME allows a significantly shorter (α-C)…Li distance of 2.418(6) Å. As was seen, however, for tertiary carbanion systems, the close approach of these two atoms need not

• multiplet at δ 2.71–2.60 ppm. Consistent with the observation of essentially trigonal planar geometry at C8 in the solid-state structure of 6-Lil·PMDTA (Figure 1), both solution isomers reveal significantly deshielded deprotonated carbon centres. Hence, observed shifts of δ 67.1 (#1) and 71.9 (#2) ppm

Stereogenic boron in 2-amino-1,1-diphenylethanol-based boronate–imine and amine complexes

• Sebastian Schlecht,
• Walter Frank and
• Manfred Braun

Beilstein J. Org. Chem. 2011, 7, 615–621, doi:10.3762/bjoc.7.72

• data (excluding structure factors) for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via http://www.ccdc.cam.ac.uk/data_request/cif. Solid-state structure of boronate–imine complex 8 (a) and the chosen asymmetric unit of the crystal structure of

Photoinduced electron-transfer chemistry of the bielectrophoric N-phthaloyl derivatives of the amino acids tyrosine, histidine and tryptophan

• Axel G. Griesbeck,
• Jörg Neudörfl and
• Alan de Kiff

Beilstein J. Org. Chem. 2011, 7, 518–524, doi:10.3762/bjoc.7.60

• crystallization in near quantitative yield. Photochemistry of the tryptophan derivative 10 In contrast to all other – colorless – phthalimides of the proteinogenic amino acid series, the tryptophan derivative 10 is bright yellow. This compound, which we crystallized and whose solid-state structure was determined

Anion receptors containing thiazine-1,1-dioxide heterocycles as hydrogen bond donors

• Hong-Bo Wang,
• James A. Wisner and
• Michael C. Jennings

Beilstein J. Org. Chem. 2010, 6, No. 50, doi:10.3762/bjoc.6.50

• formed by the NH protons, the 2-CH proton of the central aryl ring and two of the ortho-protons of the terminal phenyl rings of 1 in a planar syn-syn binding conformation similar to that observed in the solid state structure of 2 with DMSO (Figure 1B). This conclusion is supported by the observation of

Synthesis and binding studies of two new macrocyclic receptors for the stereoselective recognition of dipeptides

• Ana Maria Castilla,
• M. Morgan Conn and
• Pablo Ballester

Beilstein J. Org. Chem. 2010, 6, No. 5, doi:10.3762/bjoc.6.5

• the solid-state structure of receptor 1 (Figure 7). Before undertaking the study of the binding and molecular recognition properties of the receptor series, and due to their tendency to aggregate in solution, we quantified their dimerization constants in chloroform. The calculation of the dimerization

• adopt a conformation with a cavity size large enough to include a peptidic substrate, the X-ray structure obtained for antiparallel receptor 1 shows the collapse of the designed cavity. Although crystal packing may contribute to this conformational change to some degree, the solid-state structure of 1

• data, NMR spectra of selected compounds and crystallographic data for the solid-state structure of 1. Supporting Information File 27: Synthesis and binding studies of two new macrocyclic receptors for the stereoselective recognition of dipeptides Supporting Information File 28: CIF for the solid-state

Self-association of an indole based guanidinium-carboxylate-zwitterion: formation of stable dimers in solution and the solid state

• Carolin Rether,
• Wilhelm Sicking,
• Roland Boese and
• Carsten Schmuck

Beilstein J. Org. Chem. 2010, 6, No. 3, doi:10.3762/bjoc.6.3

• interact at concentration > ca. 15 mM. However, the exact nature of these larger aggregates is unclear at the moment. We were able to determine the solid state structure of 2. X-ray quality crystals of compound 2 were obtained by slow evaporation of a dimethyl sulfoxide solution. X-ray crystallography

• fits quite well to the X-ray structure. Though the calculated structure of dimer 2·2 is not completely symmetric like the X-ray structure, all the hydrogen bond distances, as well as the torsion angle match pretty well (Figure 9). In the solid state structure, the hydrogen bond distances between the

• , DFT calculations suggest that the dimers are significantly less stable than dimer 1·1 despite the overall similarity of the binding interactions. The calculated dimerisation enthalpy for dimer 2·2 is only 66% of that for dimer 1·1. This is most likely due to two reasons. As the solid state structure

A simple route for renewable nano- sized arjunolic and asiatic acids and self- assembly of arjuna- bromolactone

• Braja G. Bag,
• Partha P. Dey,
• Shaishab K. Dinda,
• William S. Sheldrick and
• Iris M. Oppel

Beilstein J. Org. Chem. 2008, 4, No. 24, doi:10.3762/bjoc.4.24

• efficiently in various aromatic solvents. Scanning electron micrographs of the dried gels of 3 revealed a fibrous network structure having fibers of submicron diameters. Solid state structure of 3 revealed a 1D-helical self-assembly indicating the specific mode of packing of the molecules within the fibrillar

Variations in product in reactions of naphthoquinone with primary amines

• Marjit W. Singh,
• Anirban Karmakar,
• Nilotpal Barooah and
• Jubaraj B. Baruah

Beilstein J. Org. Chem. 2007, 3, No. 10, doi:10.1186/1860-5397-3-10

• identification of a suitable system for obtaining homogeneous solutions with primary amines. The solid state structure of (a) 1 and (b) 2 (drawn with 20% thermal ellipsoids). (a) The crystal structure of 3 and (b) weak interactions in 3 leading to self-assembly, (c) Structure of 4 (drawn with 20% thermal

The vicinal difluoro motif: The synthesis and conformation of erythro- and threo- diastereoisomers of 1,2-difluorodiphenylethanes, 2,3-difluorosuccinic acids and their derivatives

• David O'Hagan,
• Henry S. Rzepa,
• Martin Schüler and
• Alexandra M. Z. Slawin

Beilstein J. Org. Chem. 2006, 2, No. 19, doi:10.1186/1860-5397-2-19

• ). For the threo- 21 isomer, there are two vicinal 3JHF couplings of similar and large magnitude (26.3 and 23.6 Hz) suggesting that rotamer d, with two trans 3JHF relationships and again with the fluorines gauche, is the most significant contributor to the solution conformation. In the solid state

• structure of threo-21 in Figure 9, the C-F bonds adopt a gauche relationship and the phenyl and ester groups are anti to each other. This is consistent with the preference for rotamer d found in solution. Attempts to crystallise erythro-21 as its free carboxylic acid resulted only in the formation of