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Published on: November 9, 2019
Fuel Acid Drives Base Catalysis and Supramolecular Cage-to-Device Transformation under Dissipative Conditions
Debabrata Mondal1, Amit Ghosh1, Indrajit Paul1
1Center of Micro- and Nanochemistry and (Bio)Technology (Cμ), Organische Chemie I, Adolf-Reichwein-Str. 2, D-57068 Siegen, Germany.
Abstract:
In State-I, a mixture comprising a DABCO-bridged tris(zinc-porphyrin) double decker and a free biped (=slider), catalysis was OFF. Acid addition (TFA or Di-Stefano fuel acid) to State-I liberated DABCO-H+ while generating a highly dynamic slider-on-deck device (State-II). The released DABCO-H+ acted as a base organocatalyst for a Knoevenagel reaction (catalysis ON). The system was reversed to State-I (catalysis OFF) by reducing the acidity in the system (by adding DBU or via the fuel-derived base).
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