Employing enabling tools (flow and mechanochemistry) for organocatalytic processes

Expedient Organocatalytic Aza-Morita-Baylis-Hillman Reaction Through Ball-Milling

A ball-milling enabled tertiary amine catalysed aza-Morita-Baylis-Hillman reaction is reported. The reaction process does not require solvent, has significantly shorter reaction times than previous methods, and is reported on a range of imines and acrylate Michael acceptors across more than 25 examples. A 12-fold scaled-up example is also reported as well as experimental comparisons to solution based experiments and neat-stirred reactions including (ACS Sustainable Chem. Eng., 2020, 8, 17876-17881. [link])

N-Heterocyclic Carbene Acyl Anion Organocatalysis by Ball-Milling

The ability to conduct N-Heterocyclic carbene catalysed acyl anion chemistry under ball-milling conditions is reported for the first time. This process has been exemplified through applications to intermolecular-benzoin, intramolecular-benzoin, intermolecular-Stetter and intramolecular-Stetter reactions including asymmetric examples and demonstrates that this mode of mechanistically complex organocatalytic reaction can operate under solvent minimised conditions (ChemSusChem, 2019, 13, 131-135. [link] [Hot Topic: Organocatalysis]).