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PHO ligand

The starting point for walphos was also the Ugi amine. Like josiphos, wal-phos ligands are modular but form eight-membered metallocycles due to the... [Pg.844]

Subsequently, Burgess and coworkers developed the chiral carbenoid ligands 32 (Scheme 29.10), which were structurally related to the JM-PHOS ligand [39, 40]. [Pg.1042]

Scheme 29.10 Carbenoid imidazolylidene ligands based on the JM-PHOS ligand (32). Scheme 29.10 Carbenoid imidazolylidene ligands based on the JM-PHOS ligand (32).
The correctness of the stereochemical prediction based on the comparison of the NMR data of each diastereomeric pair could be assessed through this study, furthermore, the observation that the methyl protons and the vinylic proton of the (Ra,Sc)- and of the (Ra,Rc)-diastereomer, respectively, show an NOE signal with the ortho and meta protons of only one binaphthyl moiety clearly indicates that the rotation around the P—N bond is hindered. In this structure the presence of a bulky chlorine substituent in the 8-position may account for the restricted rotation and a similar behavior would be expected for all 8-substituted QUINA-PHOS ligands. [Pg.256]

Scheme 7 Synthesis of optically pure P-PHOS ligands. Scheme 7 Synthesis of optically pure P-PHOS ligands.
The catalyst bearing BINAP (6.10and6.11) (developed by Noyori s group) or P-Phos ligands 6.70 (developed by Professor Albert Chan which is more active and selective than the... [Pg.256]

In 2006, Chan group prepared a series of chiral diphosphine ligands denoted as PQ Phos by employing the atropdiastereoselective Ullmann coupling and ring closure reactions as key steps. These PQ Phos ligands have been successfully applied in the catalytic asymmetric hydrogenation of quinolines with 72 94% ee (Scheme 10.6) [8]. [Pg.304]

Migration of alkenyl-Pd(II) intermediates may occur during Heck reaction of enol phosphates, but it may be suppressed by using the X-Phos ligand. ... [Pg.347]

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],... [Pg.707]

Despite the great success of the BINAP (1) ligand in the arylation of anilines, the amination of aryl chlorides required high reaction temperatures and high catalyst loadings. In contrast, the Q-Phos ligand (24) in combination with [Pd(dba)2] was capable of promoting the amination of aryl bromides and chlorides at room temperature or at 100°C, respectively (Scheme 13.64) [95]. [Pg.1032]


See other pages where PHO ligand is mentioned: [Pg.150]    [Pg.709]    [Pg.449]    [Pg.209]    [Pg.316]    [Pg.129]    [Pg.218]    [Pg.41]    [Pg.42]    [Pg.43]    [Pg.44]    [Pg.471]    [Pg.476]    [Pg.43]    [Pg.255]    [Pg.256]    [Pg.164]    [Pg.137]    [Pg.697]    [Pg.318]    [Pg.18]    [Pg.20]    [Pg.749]    [Pg.749]    [Pg.133]    [Pg.158]    [Pg.251]    [Pg.276]    [Pg.344]    [Pg.345]   
See also in sourсe #XX -- [ Pg.29 , Pg.43 ]




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Ligands P-Phos

Phos

X-Phos ligand

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