Highly efficient asymmetric synthesis process directed for optically pure medicines

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The aim of this research is to establish the methodology for i)simple preparation of tricyclic "roofed" 2-oxazolidinones, 2-imidazolidinones and 2-thiazolidinones with comformational rigidity and steric congestion as extremely powerful chiral auxiliaries by catalytic resolution, and ii)excellent asymmetric reactions with bicyclic 2-amino alcohols, 1,2-diamines and 2-aminothiols derived from the above tricyclic compounds and their derivatives.(1)Easy access to highly efficient chiral auxiliaries by kinetic resolutionThe optically active "roofed" 2-oxazolidinones, 2-imidazolidinones and 2-thiazolidinones were readily obtained from kinetic resolution with oxazaborolidine catalysts, which is an alternative method for optical resolution with "MAC-acid" (2-exo-methoxy-1-apocamphanecarboxylic acid).(2)Development of highly efficient chiral ligandsBicyclic "roofed" 2-amino alcohols, 1,2-diamines and 2-aminothiols derived from the corresponding tricyclic compounds have been proven to be good to excellent chiral ligands for following metal-catalyzed asymmetric reactions :i)"2-Aminoalcohol" ligands :a)asymmetric borane reduction of ketones with oxazaborolidine-borane system.b)Practical synthesis of versatile chiral synthons, 4,5-dimethoxy-2-oxazolidinone and 4,5-demethoxy-2-imidazolidinone.c)asymmetric aldol reaction with Cu(II) catalyst.ii)"cis-1,2-Diamine" ligands :a)Ruthenium (II)-catalyzed asymmetric transfer hydrogenation of ketones.iii)"2-Aminothiol" ligands:a)Pd (II)-catalyzed asymmetric alkylation of allylacetates.b)Cu (II)-catalyzed asymmetric Diels-Alder reaction.