Premium
Structural Investigations on Enantiopure P–OP Ligands: A High‐Performing P–OP Ligand for Rhodium‐Catalysed Hydrogenations
Author(s) -
FernándezPérez Héctor,
Balakrishna Bugga,
VidalFerran Anton
Publication year - 2018
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.201701760
Subject(s) - rhodium , chemistry , enantiopure drug , steric effects , ligand (biochemistry) , phosphine , chelation , medicinal chemistry , asymmetric hydrogenation , catalysis , stereochemistry , diol , organic chemistry , enantioselective synthesis , biochemistry , receptor
A second generation of phosphine–phosphite (P–OP) ligands, incorporating a more sterically bulky phosphite group than previous P–OP ligand designs, gave very efficient catalysts for the Rh‐catalysed asymmetric hydrogenation of a diverse array of substrates (11 examples, 93–99 % ee ) containing structurally diverse substituents and chelating groups at the C=C double bond. The presence of the sterically bulky ( S a )‐3,3′‐diphenyl‐5,5′,6,6′,7,7′,8,8′‐octahydro‐[1,1′‐binaphthalene]‐2,2′‐diol‐derived phosphite fragment caused significant increases in enantioselectivity (up to Δ ee = 58 %), and provided improved results compared to those obtained with the first generation of P–OP‐derived rhodium catalysts {i.e., rhodium complexes incorporating phosphine–phosphite ligands with ( R a )‐ and ( S a )‐BINOL‐derived phosphite groups; BINOL = [1,1′‐binaphthalene]‐2,2′‐diol}. Overall, the optimal ligand L8 provided very high enantioselectivities for a range of structurally diverse olefins (up to 99 % ee ).