Croatica Chemica Acta, Vol. 95 No. 4, 2022.
Original scientific paper
https://doi.org/10.5562/cca3954
Acid-Base Catalysis in the Mechanochemical Formation of a Reluctant Imine
Leonarda Vugrin
; Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
Ivica Cvrtila
; Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
Marina Juribašić Kulcsár
; Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
Ivan Halasz
; Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
Supplements: cca3954-supplement.pdf
Abstract
Understanding the mechanism of action of catalytic amounts of additives on mechanochemical reactions is a growing and increasingly important topic in mechanochemistry, because it allows a significant level of control over the course and selectivity of mechanochemical reactions. Here, we investigate catalysis in the mechanochemical formation of an imine derived from p-nitrobenzaldehyde and p-nitroaniline, which did not occur by neat grinding at room temperature. Based on in situ reaction monitoring and DFT computations, we explain efficient catalysis observed for carboxylic acids, which suitably position the reacting partners and facilitate proton transfer. We also observe the formation of an aminal intermediate and conclude that the final elimination step in imine formation may proceed from either the hemiaminal or the aminal.
Keywords
imine; mechanochemistry; acid-base catalysis; mechanism; Raman monitoring
Hrčak ID:
305640
URI
Publication date:
5.7.2023.
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