P-Phos

S)-Xylyl-BINAP-RuCl2-(S.S)-DPEN] [CTH-(R)-Xylyl-P-Phos-RuCl2 (/. / -DPEN]... 

BINAP itself has been shown to be effective for the reduction of a,/ -unsatu-rated carboxylic acids [8, 36, 177, 215-220], but Hg-BINAP often provides higher ee-values [193, 194]. The ruthenium complex with P-Phos provides high selectiv-... 

With a BINAP-Ru [3d,104], Hg-BINAP-Ru [102], or P-Phos-Ru [25] catalyst, the anti-inflammatory drugs (S)-ibuprofen and (S)-naproxen could be efficiently synthesized via enantioselective hydrogenation (Scheme 26.9). In these cases, high hydrogenation pressure and low temperature are required to achieve good enantioselectivity. With an (R)-BIPHEMP-Ru catalyst, (S)-2-(4-fluorophenyl)-3-methylbutanoic acid, a key intermediate for the synthesis of the calcium antago-... 

P-Phos Ar = C6H5 Tol-P-Phos Ar = 4-CH3C6H4 Xyl-P-Phos Ar = 3,5-(CH3)2C6H3... 

The hydrogenation of a number of aromatic ketones is shown in Figure 37.30. Noyori s very effective Ru-diphosphine-diamine technology was developed by several companies. It is not clear on which scale the processes developed by Takasago (dm-binap = 3,5-xylyl-binap) [16] and Dow/Chirotech [109-111] for the reduction of substituted acetophenones are actually applied commercially. Using the Xyl-PhanePhos-dpen catalyst, a highly efficient bench-scale process was developed for the hydrogenation of p-fluoroacetophenone (ee 98%, TON 100000, TOF 50000 IT1 at r.t., 8 bar) [109]. Ru-P-Phos (licensed to Johnson Matthey [112]) achieved ee-values >99.9% and TON up to 100000 for sev-... 

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