SYNTHESIS OF CHIRAL 1,2-DIAMINES VIA ASYMMETRIC ADDITION OF RLI TO 1,2-DIIMINES

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This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. C2-symmetric chiral 1,2-diamines with a chiral center in the ¿-position have found wide application as effective catalyst ligands. They are analogous of the drug cis-platin and are used in cancer treatment research. 1,2-Diamines are also key reactants in the synthesis of natural products. Conventional methods of chiral 1,2-diamine syntheses are labor intensive, requiring stochiometric amounts of a chiral auxiliary. One of the novel ways to synthesize chiral 1,2-diamines is by the addition of RLi compounds to 1,2-diimines in the presence of catalytic amounts of a chiral ligand. Despite the fact that addition of RLi to monoimines in the presence of a variety of different chiral ligands has been exhaustively studied, only one paper has been published to date describing the addition of RLi to 1,2-diimines. The most successful chiral ligands used in reactions with monoimines are bis-oxazolines. No research detailing addition to 1,2-diimines in the presence of chiral bis-oxazolines has been published. The proposed research is to investigate the enantioselectivity of the addition of RLi reagents to 1,2-diimines in the presence of stochiometric and substochiometric amounts of chiral bis-oxazoline based ligands. The results of this work should establish a methodology that will allow a straight-forward synthesis of chiral C2-symmetric 1,2-diamines.