Organocatalytic enantio selective syntheses of l-(-)-733, 061, (2S,3S) - methyl-3-aminopiperidine-2-carboxylate, their c3-epimer,(s) -2, 3-diaminopropionates and Cu-catalyzed synthesis of chiral beta -hydroxy or bita -tosylamino triazoles, benzyl/allyl
