Some novel polymer-supported optically active phase transfer catalysts: 1. Synthesis

The synthesis and characterization of 27 novel polystyrene resin-supported optically active phase transfer catalysts is described. The first group of five catalytic species are essentially supported tetraethylene oxide derivatives each carrying a terminal chiral group. The second group consists of resins loaded with a protected galactose function along with a range of onium salt and oligoether catalysts. The third group are analogous to the second with a protected fructose residue replacing the galactose one. In the fourth group some attempt has been made to define the stereochemical relationship between the chiral species and the catalytic one, by attaching a chiral diphosphine to the support. Similarly, a phosphinated sugar, ephedrine and quinine have been attached. In the final group a chiral acetal function has been synthesized on the resin, and this function subsequently modified with a phosphonium salt and an oligoether each as the phase transfer catalytic species. In general good loadings were achieved as indicated by changes in elemental analyses and shifts in the infra-red absorption spectra of resins.