A convenient method for preparing rigid-core ionic liquid crystals

• Julien Fouchet,
• Laurent Douce,
• Benoît Heinrich,
• Richard Welter and
• Alain Louati

Beilstein J. Org. Chem. 2009, 5, No. 51, doi:10.3762/bjoc.5.51

• interactions is given in Figure 1 (the interactions also being listed in Table 1). The alkyloxy chains are quite parallel, as is clear from the crystal packing given in Figure 2, with segregation between the rigid part (including iodine atoms) and the alkyloxy chains (≈20 Å, see Figure 2). The length of the

A stable enol from a 6-substituted benzanthrone and its unexpected behaviour under acidic conditions

• Marc Debeaux,
• Kai Brandhorst,
• Peter G. Jones,
• Henning Hopf,
• Jörg Grunenberg,
• Wolfgang Kowalsky and
• Hans-Hermann Johannes

Beilstein J. Org. Chem. 2009, 5, No. 31, doi:10.3762/bjoc.5.31

• . Ellipsoid representation (50% level) of compound 7 in the crystal. Packing diagram of compound 7 viewed parallel to b; hydrogen bonds C-H···O are indicated by dashed lines. Ellipsoid representation (50% level) of compound 11 in the crystal. Packing diagram of compound 11 viewed perpendicular to the bc plane

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

• arjuna-bromolactone 3. The length of the molecule (3O•••30C) is 1.26 nm. Crystal packing diagram of arjuna-bromolactone 3. A network of hydrogen bridges leading to the formation of a one-dimensional helix is observed. (a) (i) Br2/AcOH, (ii) CH2N2, (iii) separation by crystallization, (b) Zn/AcOH/RT (c

Inversion symmetry and local vs. dispersive interactions in the nucleation of hydrogen bonded cyclic n-mer and tape of imidazolecarboxamidines

• Sihui Long,
• Venkatraj Muthusamy,
• Peter G. Willis,
• Sean Parkin and
• Arthur Cammers

Beilstein J. Org. Chem. 2008, 4, No. 23, doi:10.3762/bjoc.4.23

• nuances inherent in crystal packing engender boundless diversity in the arrangements of hydrogen bonded organic solid states. Due to its relative strength and its directional nature, the hydrogen bond has drawn much attention as a structural element in the design of crystalline phases [1][2][3][4][5]. The

• phase [23]; although, exceptions have been noted [24]. Musing about this issue, Brock and Dunitz state, “Inversion centers are especially favorable for crystal packing because they diminish like-like interactions and are uniquely compatible with translation.” [25] Symmetry is a powerful component in

Shape- persistent macrocycle with intraannular alkyl groups: some structural limits of discotic liquid crystals with an inverted structure

• Sigurd Höger,
• Jill Weber,
• Andreas Leppert and
• Volker Enkelmann

Beilstein J. Org. Chem. 2008, 4, No. 1, doi:10.1186/1860-5397-4-1

• ). The remaining portions of the alkyl chains are located above and below the rigid phenyl acetylene backbone of the rings which is in both cases relatively flat. Although the crystal packing shows that the alkyl chains are sandwiched between the macrocycles, there exist still some close contacts between

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

• structure is shown in Figure 5. In the X-ray crystal structure of erythro-19 both of the carboxylic acid carbonyl oxygens adopt a syn periplanar conformation with respect to the C-F bonds. In the crystal packing, the carboxylate groups of two neighbouring molecules are hydrogen bonded and this clearly

• [29][30]. X-ray structure of erythro-22. Crystal packing of erythro-22 clearly indicating intermolecular hydrogen bonding. X-ray structure of threo-22. The conformations of erythro- and threo- 23 are very different as a consequence of each conformation preserving a vicinal fluorine gauche relationship

Hydrogen bonding patterns in the cocrystals of 5-nitrouracil with several donor and acceptor molecules

• Reji Thomas,
• R. Srinivasa Gopalan,
• G. U. Kulkarni and
• C. N. R. Rao

Beilstein J. Org. Chem. 2005, 1, No. 15, doi:10.1186/1860-5397-1-15

• . Introduction Crystalline molecular solids exhibit properties- chemical reactivity, electrical, optical or magnetic – unique to their crystal structure. This justifies the growing interest in designing and preparing molecular crystals with desired properties and understanding crystal packing, which are clearly