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New macrocyclic molecules are described containing two or three p-tert-butylcalixC4Iarene subunits connected via their oxygen atoms. These macrocycles are available by two general methods which are capable of producing assemblies with bridges of varying rigidity and length.

We have reinvestigated temperature effects on the rates of hydrolysis of 0.0585M sucrose in 0.57M HCl solutions over the range of 10-40°C using polarimetry as a physical method to follow the reaction while simultaneously analyzing the solutions by HPLC for the disappearance of sucrose and by GLC for the appearance of glucose. When the polarimetric data are corrected for the mutarotation lag, the energy of activation values are the same by all three analytical methods and are temperature-independent.The hydrolysis of sucrose has been of central importance in the development of the subject of chemical kinetics [l]. Interestingly the question as to whether or not the Arrhenius energy of activation changes with temperature has remained unresolved for over 40 years [1,2]. While the apparent answer to the question was that the energy of activation does change with temperature based on the work of Moelwyn-Hughes We have reinvestigated temperature effects on the rates of hydrolysis of 0.0585 M sucrose with 0.57M HC1 solutions over the range of 10-40°C using polarimetry as a physical method to follow the process while simultaneously analyzing the solutions by liquid chromatography for the disappearance of sucrose and by gas chromatography for the appearance of glucose. Our results for the first-order reaction are summarized in Table I along with the comparison data of Moelwyn-Hughes, Leininger and Kilpatrick, and Heidt and Purves.It must be appreciated that in spite of a voluminous literature on sucrose

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