A New N-Trityl-Substituted Aminopyridinato Titanium Catalyst for Hydroamination and Hydroaminoalkylation Reactions - Unexpected Intramolecular C-H Bond Activation

摘要

Sterically demanding 2,6-bis(tritylamino)pyridine is used for the synthesis of a mono(2,6-diaminopyridinato) titanium complex that undergoes unexpected intramolecular C-H bond activation to give access to an unusual 1-titanaisoindoline derivative. Both titanium complexes do not show high catalytic activity for hydroaminoalkylation reactions of alkenes but exceptional results are obtained in the field of alkene, alkyne, and allene hydroamination including room temperature activity for intramolecular alkene hydroamination, excellent regioselectivity of intermolecular alkyne and allene hydroamination as well as selectivity for hydroamination over hydroaminoalkylation during cyclization reactions of primary aminoalkenes.