title: New chiral lanthanide amide ate complexes for the catalysed synthesis of scalemic nitrogen-containing heterocycles.
abstract: New chiral binaphthylamido yttrium and ytterbium ate complexes with lithium and potassium counterions have been synthesised and characterised. X-ray structures have been obtained for [Li(thf)4][Ln{(R)-C20H12(NC5H9)2}2] (Ln=Yb, Y) and [K(thf)5][Yb{(R)-C20H12(NCH2CMe3)2}2] as isostructural complexes. The efficiency of these complexes for the enantioselective intramolecular hydroamination was examined. [Li(thf)4][Yb{(R)-C20H12(NC5H9)2}2] afforded the highest enantiomeric excess (up to 87 %) for the synthesis of a spiropyrrolidine, while [Li(thf)4][Y{(R)-C20H12(NC5H9)2}2] proved to be slightly more active. The role of the counter cation in the active catalytic species was evidenced by the comparison between lithium and potassium ate complexes. The most active catalyst of this series, [Li(thf)4][Yb{(R)-C20H12(NCH2CMe3)2}2], was successfully used for the cyclisation of aminopentenes with internal double bonds.
authors: Laboratoire de Catalyse Moléculaire, ICMMO, UMR CNRS 8182, Université Paris-Sud, 91405 Orsay, France.
authors: Isabelle
authors: I
authors: Aillaud
authors: Jacqueline
authors: J
authors: Collin
authors: Carine
authors: C
authors: Duhayon
authors: Régis
authors: R
authors: Guillot
authors: Dmitrii
authors: D
authors: Lyubov
authors: Emmanuelle
authors: E
authors: Schulz
authors: Alexander
authors: A
authors: Trifonov
mesh_terms: D000577:Amides / Q000737:chemistry*; D002384:Catalysis; D018360:Crystallography, X-Ray; D003500:Cyclization; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D008094:Lithium / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D009584:Nitrogen / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011188:Potassium / Q000737:chemistry; D015018:Ytterbium / Q000737:chemistry*; D015019:Yttrium / Q000737:chemistry*
chemical_list: D000577:Amides; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; D015019:Yttrium; D008094:Lithium; D015018:Ytterbium; D009584:Nitrogen; D011188:Potassium