Hydroamination ytterbium complexes

The catalytic activity of the ytterbium complex 170 was investigated in the hydroamination/cyclization reactions of aminoalkenes. Various nonactivated aminoalkenes were used as substrates (Scheme 43). The reaction scope is limited to five-membered ring formation. The aminoalkenes bearing bulky geminal substituents in P-position to the amino group are more reactive and could be... 

Ytterbium and lutetium ionic complexes, derived from enantiopure substituted (R)-binaphthylamine ligands of the general formula [Li(THF) ][Ln[(f )C2oHi2(NR)2]2], have been investigated as catalysts for hydroamination/cyclization of several unsatu- rated amines CH2=CH(CH2) C(R2)CH2NH2 (n = 1 or 2). Complexes with isopropyl or cyclohexyl substituents on nitrogen atoms were found to be efficient catalysts for the formation of N-containing heterocycles under mild conditions with enantiomeric excesses up to 78%.124... 

Organolanthanide-catalyzed intermolecular hydrophosphination is a more facile process than intermolecular hydroamination. The reaction of alkynes, dienes, and activated alkenes with diphenylphosphine was achieved utilizing the ytterbium imine complex 9 (Fig. 8) as catalyst [185-188]. Unsymmetric internal alkynes react regioselectively, presumably due to an aryl-directing effect (48) [186]. 

---