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We report herein the observation of a hexameric structure of a hydroxyresorc[4]arene in the solid state, enclosing a large interior space. This artificial molecular container is stabilized only by hydrogen bonds. The tendency to form aggregates in solution is demonstrated mainly by means of ESI‐MS methods.

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Cyclization of resorcinol monoalkyl ethers with aliphatic aldehydes leads to the corresponding racemic mixtures of C4‐symmetric rccc‐resorc[4]arenes. Separation of these isomers was achieved by mono‐O‐functionalization of the rccc‐2,8,14,20‐tetramethylresorc[4]arene (2) with (S)‐(+)‐10‐camphorsulfonyl chloride leading to a diastereomeric mixture of (+)‐5a and (−)‐5b. After removal of the chiral auxiliary the inherently chiral pure enantiomers (+)‐2 and (−)‐2 were obtained. Further enantiomerically pure rccc‐resorc[4]arenes were obtained by cyclization of (+)‐3‐[(2S)‐2‐methylbutoxy]phenol (6) followed by chromatographic separation. The resulting diastereomeric resorc[4]arenes (+)‐7a and (−)‐7b were examined by CD spectroscopy, showing a perfect mirror image in all solvents examined. This indicates that the resorcarene cavities of (+)‐7a and (−)‐7b are essentially enantiomers of each other. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

20-tetra(n-undecyl)resorc[4]arene, 1, and its Ca salt, 2, are described. Structural data were analyzed in terms of supramolecular packing motifs of the constituent amphiphilic macrocycles. Monolayer experiments indicate that a similar packing arrangement can be predicted for monolayers of 1 spread at the air-water interface. CaCO 3 (calcite) single crystals were grown underneath monolayers of 1 with highly uniform (012) orientation. This particular orientation was observed for a variety of structurally dissimilar monolayers indicating that macroscopic film properties such as average charge density or mean dipole moment have a decisive influence on templated calcite growth.