Expedient Trimethylaluminium‐Promoted One‐Pot Synthesis of Functional Heteroaromatic and Carbocyclic Trifluoroethylamines

Abstract

The synthesis of trifluoroethylamines as amide bond mimics is an interesting topic in current research. They are well known tools in pharmaceutical and agrochemical industry. Other methods described in literature are often restricted to few substrates. We herein report a new synthetic approach towards this class of substances. First, the trimethylaluminium-promoted generation of a trifluoromethyl-ketimine from the corresponding trifluoromethyl ketone and an aniline derivative was investigated. Next, the ketimine was converted into the trifluoro-A C H T U N G T R E N N U N G ethylamines in a one-pot reaction by simple addition of borane-methyl sulfide complex.

Chiral Phosphoric Acid Catalyzed Transfer Hydrogenation: Facile Synthetic Access to Highly Optically Active Trifluoromethylated Amines

“…developed a diastereoselective reductive amination of aryl trifluoromethyl ketones 9. During the preparation of this manuscript, the research group of Bräse10 and later that of Zhou11 reported an achiral Lewis acid mediated reductive amination of aromatic trifluoromethyl ketones and an enantioselective palladium‐catalyzed hydrogenation of perfluorinated nonactivated ketimines, respectively. Although the yields as well as the enantioselectivities are good to high, in the latter contribution the drawbacks are the use of relatively high pressures of hydrogen and the expensive and toxic transition‐metal catalyst for the transformation.…”