Iron(II) complexes for the efficient catalytic asymmetric transfer hydrogenation of ketones.
Iron(II) carbonyl compounds of the type trans-[Fe(NCMe)(CO)(P-N-N-P)][BF(4)](2) bearing the ethylenediamine-derived diiminodiphosphine ligands (R,R)- or (S,S)-1,2-diphenyl-1,2-diaminoethane were synthesized and characterized, including by their crystal structures. The new complexes are suitable precatalysts for the transfer hydrogenation of ketones at room temperature, giving turnover frequencies of up to 2600 h(-1) with low catalyst loadings (0.025-0.17%). Screening experiments showed that the precatalysts are able to produce alcohols from a wide range of simple ketones. For sterically demanding prochiral ketones, excellent enantioselectivities were obtained (up to 96% ee).
Meyer
Nils
N
Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada.
Lough
Alan J
AJ
Morris
Robert H
RH
D000438:Alcohols / Q000737:chemistry; D002384:Catalysis; D005296:Ferrous Compounds / Q000737:chemistry*; D006865:Hydrogenation; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D010084:Oxidation-Reduction
D000438:Alcohols; D005296:Ferrous Compounds; D007659:Ketones