Palladium as catalyst for

For the activation of a substrate such as 19a via coordination of the two carbonyl oxygen atoms to the metal, one should expect that a hard Lewis acid would be more suitable, since the carbonyl oxygens are hard Lewis bases. Nevertheless, Fu-rukawa et al. succeeded in applying the relative soft metal palladium as catalyst for the 1,3-dipolar cycloaddition reaction between 1 and 19a (Scheme 6.36) [79, 80]. They applied the dicationic Pd-BINAP 54 as the catalyst, and whereas this type of catalytic reactions is often carried out at rt or at 0°C, the reactions catalyzed by 54 required heating at 40 °C in order to proceed. In most cases mixtures of endo-21 and exo-21 were obtained, however, high enantioselectivity of up to 93% were obtained for reactions of some derivatives of 1. [Pg.237]

K Kohler, M Wagner, L Djakovitch. Supported palladium as catalyst for carbon-carbon bond construction (Heck reaction) in organic synthesis. Catal Today 66 105-114,2001. [Pg.400]

See for example Alimardanov A, Schmieder-van de Vondervoort L, deVries AHM, de Vries JG. Use of homeopathic ligand-free palladium as catalyst for aryl-aryl coupling reactions. Adv Synth Catal. 2004 346 1812-1817. [Pg.281]

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