Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Chelate ring treatment with base

As stated earlier, Knowles and co-workers developed an efficient asymmetric catalyst based on the chiral bisphosphine, R,R-DIPAMP (2), that has chirality at the phosphorus atoms and can form a 5-membered chelate ring with rhodium. (Digital Specialty Chemical has optimized this process, and both antipodes of DIPAMP are available in kilogram quantities.) [Rh(COD)(R,R-DIPAMP)]+BF4 (13) has been used by Monsanto for the production of L-dopa (12), a drug used for the treatment of Parkinson s disease, by an asymmetric reduction of the Z-enamide, 14a, in 96% ee (Scheme 12.1). The pure isomer of the protected amino acid intermediate, 15a, can be obtained on crystallization from the reaction mixture because it is a conglomerate.17... [Pg.189]

See other pages where Chelate ring treatment with base is mentioned: [Pg.67]    [Pg.188]    [Pg.312]    [Pg.54]    [Pg.60]    [Pg.721]    [Pg.245]    [Pg.697]    [Pg.212]    [Pg.184]    [Pg.4961]    [Pg.212]    [Pg.39]    [Pg.192]    [Pg.11]    [Pg.4960]    [Pg.184]    [Pg.3638]    [Pg.6357]    [Pg.147]    [Pg.88]    [Pg.226]    [Pg.195]    [Pg.311]    [Pg.326]    [Pg.705]    [Pg.962]    [Pg.330]    [Pg.596]    [Pg.23]    [Pg.70]    [Pg.865]    [Pg.197]    [Pg.19]    [Pg.1608]    [Pg.131]    [Pg.215]    [Pg.97]    [Pg.56]    [Pg.88]    [Pg.75]   
See also in sourсe #XX -- [ Pg.107 ]



SEARCH



Chelate rings

Chelating bases

Treatment with

© 2024 chempedia.info