Synthesis Of Chiral Ligands Containing N And Their Applications In Some Asymmetric Catalysis

1. Asymmetric Henry reaction catalyzed by bifunctional copper-based catalystsWe have successfully synthesized bifunctional ligands (L1-L8) from commercially available 2-amino-1,2-diphenylethanol, (1R,2S)-cis-1-amino-2-indanol and salicylaldehyde. The yields are high and the purifications just through simple recrystallization. All of the chiral ligands are stable in air for several months. Ligand L3 was employed into asymmetric addition of nitromethane to aldehyde (Henry) reaction in the present of Cu(OAc)2·H2O with good results of good yield (up to 74%) and moderate enantioselectivities (up to 81% ee).2. Chiral amino amides for the ruthenium(II)-catalyzed transfer hydrogenation reaction of ketones in waterAmide ligands L12-L14 drived from proline were synthesized from commercially available L-proline, (2S, 4R)-4-hydroxypyrrolidine-2-carboxylic acid andα-phenethy- lamine as the chiral sources. The yields are high and all of the chiral ligands are stable in air. Ligand L12 was employed into the asymmetric hydrogen transfer reaction of ketone in water with good results of high yields (up to 95%) and good enantioselectivities (up to 89%).3. Enantioselective synthesis ofγ-hydroxy-α,β-acetylenic catalyzed by oxazolidine-titanium complexesMono-oxazolidine ligands L18-L21 were synthesized from commercially available (1R, 2S)-cis-1-amino-2-indanol and aldehyde. The yields are high and their purifications need not troublesome column chromatography, but simple recrystallization. Their 1H NMR,13C NMR,HRMS etc are characterized. We were also luck enough to got the x-ray single crystal structure. Ligand L19 was employed into the asymmetric addition of methyl propiolate to aldehyde with good results of moderate yields ( up to 81%) and good enantioselectivies (up to 83%) in the present of HMPA, DIMPEG and Ti(OiPr)4.