Synthesis of new C2- Symmetric fluoren-9-ylidene malonate derived bis(oxazoline) ligands and their application in friedel-crafts reactions

Abstract

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). © 2010 by the authors; licensee MDPI, Basel, Switzerland.