Iridium-Catalyzed Enantioselective Synthesis of Dihydroimidazoquinazolinones by Elaborate Tuning of Chiral Cyclic Ligands.

A highly efficient, enantioselective intramolecular allylation of (E)-4-(alkyl(4-oxo-3,4-dihydroquinazolin-2-yl)amino)but-2-en-1-yl methyl carbonates was developed, and the corresponding dihydroimidazoquinazolinones were prepared in high yields and enantiomeric excess. The allylation was performed under catalysis of iridium-chiral cyclic phosphoramidite complexes, in which the reactivity and enantioselectivity of the substrates were elaborately tuned by our developed chiral cyclic phosphoramidite ligands with adjustable sizes of rings.