Inclusion compounds of a diol host with xylidines: controlled stoichiometries.
The diol host, 1,1'-bis-(4-hydroxyphenyl)cyclohexane (DHPC) and a number of xylidine isomers as guests formed a series of inclusion compounds that gave rise to various host:guest ratios controlled by crystallization temperatures. For the host DHPC with a particular xylidine isomer, the number of guests included generally decreases as the crystallization temperature increases. The crystal structures of these host-guest compounds were elucidated using single-crystal X-ray diffraction. Their thermal stabilities were characterized by TG and DSC analysis. The selectivity of enclathration by the host was measured by carrying out a series of competition experiments. The kinetics of guest decomposition were studied using isothermal and non-isothermal methods and reconciled with the crystal structures.
Physico‐Chemical Aspects of Inclusion Compounds
We summarize the macro properties of organic inclusion compounds in terms of their kinetics of desorption and enclathration, their thermal stability, and the selectivity that host compounds exhibit toward a given guest from a guest mixture. We note the importance of the mechanism of enantiomeric resolution and correlate the various phenomena with the structure of the inclusion compounds. 
 
 
Keywords: 
 
molecular recognition; 
kinetics; 
thermal stability; 
selectivity
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