A mild dihydrobenzooxaphosphole oxazoline/iridium catalytic system for asymmetric hydrogenation of unfunctionalized dialins.
Air-stable P-chiral dihydrobenzooxaphosphole oxazoline ligands were designed and synthesized. When they were used in the iridium-catalyzed asymmetric hydrogenation of unfunctionalized 1-aryl-3,4-dihydronaphthalenes under one atmosphere pressure of H2 , up to 99:1 e.r. was obtained. High enantioselectivities were also observed in the reduction of the exocyclic imine derivatives of 1-tetralones.
Chemical Development, Boehringer Ingelheim Pharmaceuticals, Inc. 900 Ridgebury Road, Ridgefield, CT 06877-0368 (USA). bo.qu@boehringer-ingelheim.com.
Bo
B
Qu
Lalith P
LP
Samankumara
Shengli
S
Ma
Keith R
KR
Fandrick
Jean-Nicolas
JN
Desrosiers
Sonia
S
Rodriguez
Zhibin
Z
Li
Nizar
N
Haddad
Zhengxu S
ZS
Han
Keith
K
McKellop
Scott
S
Pennino
Nelu
N
Grinberg
Nina C
NC
Gonnella
Jinhua J
JJ
Song
Chris H
CH
Senanayake
D002384:Catalysis; D006859:Hydrogen / Q000737:chemistry*; D006865:Hydrogenation; D007097:Imines / Q000737:chemistry; D007495:Iridium / Q000737:chemistry*; D008958:Models, Molecular; D010080:Oxazoles / Q000737:chemistry*; D013237:Stereoisomerism
D007097:Imines; D010080:Oxazoles; D007495:Iridium; D006859:Hydrogen
P,N ligands; asymmetric catalysis; imines; iridium; reduction