10.1002/chem.201902049
Chemistry - A European Journal
FULL PAPER
points (300nm/330nm and 370nm), the data was fit to either a 1:1 or 1:2
binding model and the variance used to determine best fit. [37],[38]
of the reaction. The TFA-catalyzed process is a normal,
unimolecular SN1-type substitution process, whereas the rate of
the host-mediated reaction with electrophile 4a is dependent on
the concentration of nucleophile. This variable molecularity is
substrate dependent, and substrates as similar as Acknowledgements
triphenylmethanol and O-tritylethyl ether show completely
different reaction molecularity. The catalyst is also capable of a
self-destruct sequence in the presence of tritylated amines, where
fast initial reaction is rapidly turned off by destruction of the
catalyst by product, essentially a negative feedback loop. All of
these properties require strong molecular recognition of multiple
reactants in a catalytic pathway, indicating the potential of
functionalized cage hosts as enzyme-mimicking nanoreactors.
The authors would like to thank the National Science Foundation
(CHE-1708019 to R.J.H. and CHE-1626673 for the purchase of
Bruker NEO 600 and NEO 400 NMR spectrometers) for funding.
Keywords: Supramolecular chemistry · Self-assembly ·
Catalysis · Enzyme models · Molecular recognition
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