A new class of readily available and conformationally rigid phosphino-oxazoline ligands for asymmetric catalysis
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چکیده
A new class of conformationally rigid phosphino-oxazoline ligands 3 were synthesized via an efficient ortho-substitution of phenyl glycinol as the key step. Divergent synthetic routes for easy ligand modulation, as well as a procedure suitable for scale-up synthesis, were established. The catalytic potential of ligands 3 has been demonstrated in the highly enantioselective Ir-catalyzed hydrogenation of alkenes and Pd-catalyzed allylic substitution and intermolecular Heck reactions. q 2005 Elsevier Ltd. All rights reserved.
منابع مشابه
Synthesis of a new class of conformationally rigid phosphino-oxazolines: highly enantioselective ligands for Ir-catalyzed asymmetric hydrogenation.
[reaction: see text] A new class of conformationally rigid phosphino-oxazoline ligands were synthesized from readily available enantiopure phenyl glycinol. Ir complexes with these ligands are air-stable and highly enantioselective catalysts for asymmetric hydrogenation of aryl alkenes and alpha,beta-unsaturated esters in up to 99% ee.
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تاریخ انتشار 2005