Clathrates aromatic stoichiometries

Analysis. The liquid clathrates were analyzed by the integration of NMR spectra recorded on a Perkin-Elmer R20-B instrument. The aromatic stoichiometries in Table II are in most cases the average of three preparations and integrations a realistic standard deviation would be 0.2 molecules. The chemical shifts are accurate to better than 0.02 ppm. 

Molar miscibility and saturation point measurements describing liquid clathrate behavior are commonly analyzed by the integration of NMR spectra. In most cases, the aromatic stoichiometries are the average of three preparations and integrations with an acceptable standard deviation result of 0.2 molecules. A common feature of all liquid clathrate NMR spectra is the shifting of the entire spectrum 0.2-0.5 ppm downfield relative to the pure aromatic substance. 

A simple possibility for the synthesis of esters, the reaction of an acid chloride with an alcohol, was used by Schrage and Vogtle [58] for a two-step synthesis of the macrocycle 63 from the alcohol 61 and the acid chloride 62. Compound 63, an example from the field of host/guest chemistry, forms a cavity, as studied with CPK-models, which could include planar, aromatic guests. Crystals obtained from benzene/ -heptane point to a 1 2 stoichiometry of 63 and benzene according to NMR-spectroscopic data. However, whether this is a molecular inclusion complex or just a clathrate is not yet known. 

Iwamoto, T. Miyoshi, T. Miyamoto. T. Sasaki, Y. The metal amminc cyanide aromatics clathrate. I. The preparation and stoichiometry of diammincmetal(II) tetracyano-niccolate(II) dibenzene and dianiline. Bull. Chem. Soc. Jpn. 1967,40. 1174-1178. 

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