Isbut-Box: A new chiral C2 symmetric bis-oxazoline for catalytic enantioselective synthesis

Allylic alkylations catalyzed by palladium-bis(oxazoline) complexes derived from heteroarylidene malonate derivatives

A series of simple heteroarylidene malonate-type bis(oxazoline) ligands 4 and 5 were applied to the palladium-catalyzed allylic alkylation reaction, and the ligand 4a bearing a phenyl group afforded excellent enantioselectivity (up to 96% ee) for the allylic alkylation product. Other substrates were also examined, giving the allylic alkylated products in high yield but with poor ee values.

Synthesis of new C2- symmetric fluoren-9-ylidene malonate derived bis(oxazoline) ligands and their application in Friedel-Crafts reactions

A series of new C₂-symmetric fluoren-9-ylidene malonate-derived bis(oxazoline) ligands were synthesized from fluoren-9-ylidene malonate and enantiomerically pure amino alcohols via a convenient route. Their asymmetric catalytic properties in the Friedel-Crafts reactions of indoles with arylidene malonates were evaluated, and the Cu(OTf)₂ complex of a fluoren-9-ylidene malonate-derived bis(oxazoline) bearing a phenyl group showed moderate to good enantioselectivity (up to 88% ee).