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X-ray single-crystal diffraction (SCD) analysis has the intrinsic limitation that the target molecules must be obtained as single crystals. Here we report a protocol for SCD analysis that does not require the crystallization of the sample. In our method, tiny crystals of porous complexes are soaked in a solution of the target, such that the complexes can absorb the target molecules. Crystallographic analysis clearly determines the absorbed guest structures along with the host frameworks. Because the SCD analysis is carried out on only one tiny crystal of the complex, the required sample mass is of the nanogram-microgram order. We demonstrate that as little as about 80 nanograms of a sample is enough for the SCD analysis. In combination with high-performance liquid chromatography, our protocol allows the direct characterization of multiple fractions, establishing a prototypical means of liquid chromatography SCD analysis. Furthermore, we unambiguously determined the structure of a scarce marine natural product using only 5 micrograms of the compound., Chemists need reliable methods to analyse and determine molecular structures. Nuclear magnetic resonance (NMR) and mass spectrometry are indispensable tools in daily chemical research for rapidly analysing molecular structures, but, [...]

The ability of a porous coordination network to catalyze an olefin retinal isomerization reaction in the pores is determined.

A detailed spectroscopic and single-crystal x-ray diffraction studies were conducted to examine the meso-aryl-substituted [28]hexaphyrins(1.1.1.1.1.1). The findings demonstrate the first example of Mobius aromatic molecules consisting of free-base expanded porphyrins for examination of various properties of Mobius aromaticity.

The synthesis and characterization of meso-(4-(N,N-dibenzylamino)phenyl)-substituted subporphyrins that display unique absorption properties and enhanced fluorescence emission due to the intramolecular charge transfer (CT) interaction in the opposite direction are presented. Distinct CT interactions have led to large changes in the absorption spectra and drastic enhancement of the fluorescence intensity, which are used for analyzing new chemosensors.

The first synthesis and characterization of meso-aryl-substituted subchlorins is described. Large optical and electrochemical changes have accompanied the subporphyrin-to-subchlorin structural changes, which are similar to porphyrin-to-chlorin changes.

Two synthetic methods of meso-aryl-substituted subporphyrins are formulated by using the reaction of pyridine-tri-N-pyrrolylborane with a series of aryl aldehydes. The analysis has shown that meso-aryl-substituted subporphyrins can be used for constructing curved [pi]-conjugated molecules such as molecular spheres, molecular tubes and molecular belts.

Nature 495, 461-466 (2013); doi:10.1038/nature11990 Previously unnoticed ambiguities in the crystallographic data in our Article (specifically, non-negligible disorder of the miyakosyne A molecule), along with further work by three of [...]