Structure–activity relationships in group 3 metal catalysts for asymmetric intramolecular alkene hydroamination. An investigation of ligands based on the axially chiral 1,1′-binaphthyl-2,2′-diamine motif
Alkyl Complexes of Lanthanum and Samarium Supported by a Chiral Binaphthylamido Ligand. Syntheses, Structures, and Catalytic Activity in Hydroamination of Amino-1,3-dienes
F)2(μ-Me)Li(THF)] (1) or tetranuclear [(R)-C20H12(NC5H9)2]La(μ-Me)2Li(THF)[(μ-Me)Li(THF)]2} (2) complexes with methyl ligands μ-bridging lanthanide and lithium atoms. The structures of complexes 1 and 2 were established by single-crystal X-ray diffraction and solution NMR studies. These new complexes were evaluated as catalysts to promote the enantioselective hydroamination of amino-1,3-dienes.
(R)-(+)-2,2'-双(环戊基氨基)-1,1'-联萘二胺与[Li(THF)n ] 3 [LnMe 6 ](Ln = La,Sm)在THF中的反应0°C取决于金属离子的大小,导致形成三核[(R)-C 20 H 12(NC 5 H 9)2 ] Sm [(μ-Me)2 Li(THF)2(μ-Me) Li(THF)](1)或四核[(R)-C 20 H 12(NC 5 H 9)2 ] La (μ-Me)2 Li(THF)[(μ-Me)Li(THF)]2 }(2)与甲基配体μ桥接镧系元素和锂原子的配合物。配合物1和2的结构是通过单晶X射线衍射和溶液NMR研究确定的。这些新的配合物被评估为催化剂,以促进对氨基-1,3-二烯的对映选择性加氢胺化。
New Chiral Lanthanide Amide Ate Complexes for the Catalysed Synthesis of Scalemic Nitrogen-Containing Heterocycles
Newchiral binaphthylamido yttrium and ytterbium atecomplexes 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
complexes have been proven to promote the anti‐Markovnikov addition between various styrene derivatives and secondary amines efficiently. Although the reaction has to be performed at high temperature, it is realized advantageously with a 1:2 amine/alkene molar ratio to deliver the hydroamination product in a satisfactory isolated yield. Furthermore, the reaction with 2‐vinylpyridine proceeds at room temperature
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
New chiral binaphthylamido alkyl ate and neutral yttrium and ytterbium complexes have been synthesized and characterized. X-ray structures have been obtained for ate alkyl complexes [(R)C20H12(NC5H9)(2)]Y[(mu-Me)(2)Li(THF)(2)(mu-Me)Li(THF)] and [(R)-C20H12(NC5H9)(2)]Ln[(mu-Me)(2)Li(TMEDA)(mu-Me)Li(OEt2)] (Ln = Y, Yb) and for the neutral complex [(R)-C20H12(NC5H9)(2)]YCH2SiMe3(DME). Both types of complexes can be easily prepared in a one-pot procedure starting from yttrium and ytterbium chlorides and used in situ. They proved to be very efficient catalysts for enantioselective intramolecular hydroamination of aminopentenes or aminohexene at room temperature with enantionteric excesses up to 83%.