BINAP ligands asymmetric protonation

Sodeoka and co-workers " reported on an interesting access to (3-amino carbonyl compounds thanks to a palladium-catalyzed 1,4-addition of amine salts 79a-b followed by asymmetric protonation (Scheme 31.28). Once again, BINAP was found to be the ligand of choice providing the corresponding p-amino carbonyl compounds 80a-d in up... 

Enantioselective silver-catalyzed aza-Diels-Alder reactions have also been described. Whereas the use of BINAP as the chiral ligand gave only unsatisfactory enantioselectivities,367,367a Hoveyda etal 6 used the peptidic phosphine 373 which has already been used for silver-catalyzed asymmetric Mannich reactions (see Scheme 108) in the efficient Ag(i)-catalyzed cycloaddition of arylimines 449 with Danishefsky s diene (Scheme 135). After acidic work-up, the chiral pyridones 450 were obtained with excellent yields and enantioselectivities. The presence of isopropanol as a proton source is essential for obtaining high conversions and stereoselectivities. Similar to the Mannich reactions, the cycloaddition is not affected by the presence of air or the use of undistilled THF. 

Another example of the application of DFT-based calculations comes from ruthenium catalyst-based asymmetric hydrogenations of ketones. As shown in Figure 3.5, the rra 5-dihydride complex 339 with chiral BINAP as the ligand is the resting state of the catalyst. Catalysis with 339 is proposed to occur by the transfer of a hydride from the ruthenium and a proton from the amine to the carbonyl group of the substrate, e.g., acetophenone. 

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