A Switchable Catalyst Duo for Acyl Transfer Proximity Catalysis and Regulation of Substrate Selectivity

Abstract

Enzymes are encoded with a gamut of information to catalyze a highly selective transformation by selecting the proper reactants from an intricate mixture of constituents. Mimicking biological machinery, two switchable catalysts with differently sized cavities and allosteric control are conceived that allow complementary size‐selective acyl transfer in an on/off manner by modulating the effective local concentration of the substrates. Selective activation of one of two catalysts in a mixture of reactants of similar reactivity enabled upregulation of the desired product.

Heteroleptic metallosupramolecular aggregates/complexation for supramolecular catalysis

“…The next example bridges in some way the gap between the preceding ( Figure 23 ) and the present chapter because it addresses again catalysis with two catalytically active copper(I) centers held at a defined distance, now though for proximity catalysis using acyl transfer. The utility of this approach was demonstrated when a duo of catalysts was used for achieving substrate selectivity [ 133 ].…”

“… A catalyst duo allowing selective activation of one of two catalytic acylation reactions [ 133 ] upon substoichiometric amounts of iron(II). For explanations, see text.…”

“…It was no surprise, that due to the increased local concentration, the acetylation 132 + 133 → 134 did rapidly take place. Similarly, the bigger dimeric nanoswitch [Fe(Cu 2 ( 131 )) 2 ] 6+ catalyzed the acetylation of the larger substrate 136 due to size-matching [ 133 ]. In order to test the reversibility, both switches were toggled by adding and removing the iron(II) ions over 2.5 cycles demonstrating that ON/OFF catalysis was reversible and reproducible.…”