Nowadays, design of the new chiral ligands for organometallic catalysts is often based on the step-by-step increase in their complexity to improve efficiency. Herein we describe that simple in situ addition of the fluoride source to the asymmetric organometallic catalyst can improve not only activity but also enantioselectivity. Bromide−nickel diimine complexes were found to catalyze asymmetric Michael addition in low yields and ee, but activation with fluoride leads to a significant improvement in catalyst performance. The developed approach was applied to prepare several enantioenriched GABA analogues.
NaH 2 PO 2 was found to promote reductive amination. Being nontoxic, stable, environmentally benign, and available in bulk amounts, this reducing agent showed a powerful potential to compete with classical reductants applied in the target process. An E factor of 1 was achieved for the substrate scope. Different carbonyl compounds reacted with amines under the developed conditions. The reaction demonstrated a great compatibility with a wide range of functional groups. Reaction conditions were scaled up to 200-fold.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.