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Updated: May 17, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
LiCl-effect on asymmetric intramolecular hydroamination catalyzed by binaphthylamido yttrium complexes
Yulia Chapurina1, Régis Guillot, Dmitrii Lyubov
1Equipe de Catalyse Moléculaire, Univ Paris-Sud, ICMMO, UMR 8182, Orsay, F-91405, France.
Abstract:
Chiral alkyl or amido yttrium complexes were prepared from N-silyl- or N-cyclopentyl-substituted binaphthylamido ligands. According to the synthetic procedure, these complexes could be obtained in their neutral form or as heterobimetallic complexes in the presence of 1 equiv. LiCl. These new species were characterized by IR and NMR spectroscopies, elemental analyses and some of them by X-ray diffraction studies. Their efficiency as catalysts for the asymmetric intramolecular hydroamination was then evaluated with several substrates towards the synthesis of two pyrrolidines and a piperidine derivative. A cooperative effect between the lithium and the yttrium atoms was undoubtedly revealed. LiCl-containing complexes afforded indeed higher enantioselectivities than their salt-free counterparts and according to the structure of the chiral ligand, they were also the most active species.
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