COORDINATION OF CHIRAL AMINES TO COORDINATIVELY UNSATURATED CP-ASTERISK-IR-AMINO ACID COMPLEXES ALLOWS DETERMINATION OF ENANTIOMERIC PURITY

Coordinatively unsaturated complexes of the CpIr fragment to the dian ion of N-tosylamino acids combine with chiral amines in a highly diast ereoselective fashion, such that metallacycle substituents R (amino ac id side chain) and Cp are cis. Observation of adducts between the ala nine- and phenylglycine-derived complexes and (S)-alpha-methylbenzylam ine by NMR at low to ambient temperature allows determination of the e nantiomeric purity of either component, 1 to 2% impurity being easily detectable. Furthermore, alpha-methylbenzylamine was analyzed for its enantiomeric purity independent of external chiral reagent, by its con version to N,N'-bis(1-phenylethyl)urea.