Tol-P-Phos

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

It is difficult to hydrogenate benzoylacetic acid derivatives with a high optical yield. Recently, an (R)-SEGPHOS/Ru complex-catalyzed hydrogenation of the ethyl ester with an S/C of 10,000 under 30 atm of H2 afforded the S alcohol in 97.6% ee (Table of Scheme 20) [36]. MeO-BIPHEP and Tol-P-Phos also performed with a high level of enantioselection [49, 60], Hydrogenation of N-methylbenzoylacetamide with the (R)-BINAP/Ru catalyst gave the S alcohol in >99.9% ee and 50% yield [61]. 

Other P-Phos related ligands, such as the chiral 4-bis(tolylphosphino) (Tol-P-Phos) and chiral 4-bis(cyclohexylphosphino) (Cy-P-Phos) ligands, were prepared and purified in a similar, or slightly modified, manner using the appropriate phosphines. They also form mthenium complexes that have related catalytic activities [Wu Chan Acc Chem Res 39 711 2005, Au-Yeung Chan Coordination Chemistry Reviews 248 2151 2004],... 

The ligands tested were tol-binap, dipamp, P-phos, xyl-P-phos, binam, phanephos and xyl-phanephos with the results lised in Table E Table 2 shows the effect which... 

The diamine ligands that have shown the most consistent usage are DPEN (145) and diapen (146). The best bisphosphines ligands used to date have been axial bisphosphines ligands, such as BINAP (3a), tol-BINAP (3b), xyl-BINAP (3c),23 188 xyl-PhanePhos (127b),162 163 and xyl-P-Phos (120c).153... 

Extensive mechanistic studies have been conducted on the oxidative addition of aryl halides to Pd(0) complexes ligated by PPh3 in different media and with different additives175, 176. However, palladium complexes containing these ligands are not active catalysts for amination. Instead, one must consider the addition of aryl halides to palladium complexes bound by ligands relevant to amination. Studies of the mechanism of oxidative addition to palladium(O) complexes of P(tol-o)3, DPPF, BINAP, Q-phos, P(Bu-f)3 and an /V-heterocyclic carbene ligand have been reported. 

Water and aqueous organic solvents can successfully be used for carrying out the Heck reaction with aaylic acid or acrylonitrile in the aqueous phase catalyzed by phos-phine-free palladium salts for aryl iodides or P((9-Tol)3 complex of palladium for aryl bromides in the presence of inorganic bases K2CO3, Na2C03, NaHCOs, or KOH (Scheme... 

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