Ball‐Milling‐Enabled Reactivity of Manganese Metal Nicholson, William I.; Howard, Joseph L.; Magri, Giuseppina ...
Angewandte Chemie (International ed.),
October 18, 2021, Letnik:
60, Številka:
43
Journal Article
Recenzirano
Odprti dostop
Efforts to generate organomanganese reagents under ball‐milling conditions have led to the serendipitous discovery that manganese metal can mediate the reductive dimerization of arylidene malonates. ...The newly uncovered process has been optimized and its mechanism explored using CV measurements, radical trapping experiments, EPR spectroscopy, and solution control reactions. This unique reactivity can also be translated to solution whereupon pre‐milling of the manganese is required.
A manganese‐mediated reductive dimerization of arylidene malonates by ball milling is reported. The process has been optimised and its mechanism explored by CV measurements, radical trapping, and EPR spectroscopy. Control experiments identify the action of ball milling rather than mortar and pestle is necessary to realise the effective activation of manganese, which can then be used in either solution or a ball mill for subsequent reactions.
Direct Amidation of Esters by Ball Milling Nicholson, William I.; Barreteau, Fabien; Leitch, Jamie A. ...
Angewandte Chemie International Edition,
September 27, 2021, Letnik:
60, Številka:
40
Journal Article
Recenzirano
The direct mechanochemical amidation of esters by ball milling is described. The operationally simple procedure requires an ester, an amine, and substoichiometric KOtBu and was used to prepare a ...large and diverse library of 78 amide structures with modest to excellent efficiency. Heteroaromatic and heterocyclic components are specifically shown to be amenable to this mechanochemical protocol. This direct synthesis platform has been applied to the synthesis of active pharmaceutical ingredients (APIs) and agrochemicals as well as the gram‐scale synthesis of an active pharmaceutical, all in the absence of a reaction solvent.
Mechanochemical ball‐milling enabled the direct amidation of esters through simple coupling under basic conditions (see scheme). A wide range of esters underwent amidation by this method with an array of primary and secondary amides without the need for a bulk solvent, catalysts, or additives.
Efforts to generate organomanganese reagents under ball‐milling conditions have led to the serendipitous discovery that manganese metal can mediate the reductive dimerization of arylidene malonates. ...The newly uncovered process has been optimized and its mechanism explored using CV measurements, radical trapping experiments, EPR spectroscopy, and solution control reactions. This unique reactivity can also be translated to solution whereupon pre‐milling of the manganese is required.
A manganese‐mediated reductive dimerization of arylidene malonates by ball milling is reported. The process has been optimised and its mechanism explored by CV measurements, radical trapping, and EPR spectroscopy. Control experiments identify the action of ball milling rather than mortar and pestle is necessary to realise the effective activation of manganese, which can then be used in either solution or a ball mill for subsequent reactions.
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.
Having a ball: The ability to conduct mechanistically complex N‐heterocyclic carbene‐catalysed acyl anion chemistry under ball‐milling conditions is reported for the first time. This process is exemplified through applications to intermolecular‐benzoin, intramolecular‐benzoin, intermolecular‐Stetter and intramolecular‐Stetter reactions including asymmetric examples.
Direct Amidation of Esters by Ball Milling Nicholson, William I.; Barreteau, Fabien; Leitch, Jamie A. ...
Angewandte Chemie,
September 27, 2021, Letnik:
133, Številka:
40
Journal Article
Recenzirano
The direct mechanochemical amidation of esters by ball milling is described. The operationally simple procedure requires an ester, an amine, and substoichiometric KOtBu and was used to prepare a ...large and diverse library of 78 amide structures with modest to excellent efficiency. Heteroaromatic and heterocyclic components are specifically shown to be amenable to this mechanochemical protocol. This direct synthesis platform has been applied to the synthesis of active pharmaceutical ingredients (APIs) and agrochemicals as well as the gram‐scale synthesis of an active pharmaceutical, all in the absence of a reaction solvent.
Mechanochemical ball‐milling enabled the direct amidation of esters through simple coupling under basic conditions (see scheme). A wide range of esters underwent amidation by this method with an array of primary and secondary amides without the need for a bulk solvent, catalysts, or additives.
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