A straightforward in situ preparation of new chiral amido alkyl ate yttrium complexes is described. They catalysed the enantioselective cyclisation of 1,2-dialkyl-substituted aminopentenes in up to 77% ee, a significant value for this challenging transformation. Complex [(R)-L0][Y(CH2TMS)2·Li(THF)4] undergoes C–H bond activation resulting in the formation of an original dimeric heterobimetallic yttrium complex which also acts as an active precatalyst.
The in situ preparation of chiral amido alkyl ate yttrium complexes from an array of chiral N-benzyl-like-substituted binaphthyldiamines is reported. These chiral heteroleptic complexes are shown to be efficient catalysts for the enantioselective intramolecular hydroamination of primary amines tethered to sterically demanding alkenes at high reaction temperatures. Fine tuning of their chiral environment allowed up to 77% ee to be reached for the cyclization of aminoalkenes bearing 1,2-dialkyl-substituted carbon-carbon double bonds. These chiral complexes also demonstrate the ability to promote the cyclization of amine-tethered trisubstituted alkenes in up to 55% ee, as the first report of the formation of enantioenriched quaternary centers by an hydroamination reaction.