New phosphorus amides as hydrogen bonding catalysts

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New phosphorus acid amide and cyclodiphosphazane systems will be synthesized and characterized.The cooperative hydrogen bonding donors of such phosphorus amides will be applied in anion receptors as well as in hydrogen bonding catalysts.The modular constructions of the new phosphorus amides enable many structural modifications, e.g. of P=O, P=S or P=Se-units, of alkyl or aryl groups attached to N-atoms as well as with different chiral amino alcoholic- or diamino- groups.The ability for anion binding will be tested for the new phosphorus amides with different ions using UV/Vis titrations. NMR- and X-ray-analyses as well as quantum chemical computations will reveal how ions are bound by the new hydrogen bonding scaffolds.For a comparison with established hydrogen bonding catalysts, the catalytic activity of the new phosphorus amides will first be tested in non-stereoselective reactions. The new, chiral phosphorus amides will then be applied in enantioselective catalytic couplings of C-C- and C-heteroatoms. Supported by X-ray analyses, NMR-experiments and quantum chemical computations, the favored binding modes of substrates and reagents and the crucial transition structures will be studied. These results will then be employed for the design of even more efficient modular hydrogen bonding catalysts based on phosphorus amides.