Access to Enantiomerically Pure P -Chiral 1-Phosphanorbornane Silyl Ethers.

Sulfur-protected enantiopure -chiral 1-phosphanorbornane silyl ethers , are obtained in high yields via the reaction of the hydroxy group of -chiral 1-phosphanorbornane alcohol with -butyldimethylsilyl chloride (TBDMSCl) and triphenylsilyl chloride (TPSCl). The corresponding optically pure silyl ethers , are purified via crystallization and fully structurally characterized. Desulfurization with excess Raney nickel gives access to bulky monodentate enantiopure phosphorus(III) 1-phosphanorbornane silyl ethers , which are subsequently applied as ligands in iridium-catalyzed asymmetric hydrogenation of a prochiral ketone and enamide. Better activity and selectivity were observed in the latter case.