A method for synthesizing of thioesters by using a compound as a catalyst is disclosed. The compound is represented by formula I below: ##STR00001##
In formula I, R.sup.5 represents H, a substituted or unsubstituted alkyl, a substituted or unsubstituted aryl, or a substituted or unsubstituted heteroaryl; X and Y each independently represents one of H, C.sub.1-10 alkyl, C.sub.5-10 aryl, C.sub.1-10 alkyl alcohol, thiohydroxy, carbonyl, sulfonyl, sulfamoyl, carbamoyl, C.sub.1-10 alkoxycarbonyl, C.sub.1-10 alkoxycarbamoyl, C.sub.1-10 alkylamino, C.sub.1-10 alkylsulfonyl, C.sub.1-10 haloalkylsulfonyl, ureido, amido, and C.sub.1-10 alkoxylcarbamoyl; and n is 0, 1, 2, 3, 4 or 5.

The present invention discloses a diphenylamine-linked chiral bis(oxazoline) ligand without C.sub.2-symmetry of formula 3 and its synthesis method and application in an asymmetric catalytic reaction, wherein C.sub.2-symmetry is lost by introducing different groups into the diphenylamine backbone to realize precise control of electronic effect of the ligand backbone. An anthranilic acid derivative and an orthochlorobenzoic acid derivative are used as starting materials to prepare a compound of formula 1, and then the compound of formula 1 is reacted with a chiral amino alcohol compound to prepare a -bishydroxy amide compound of formula 2, and the compound of formula 2 is further subjected to condensation to obtain the diphenylamine-linked chiral bis(oxazoline) ligand without C.sub.2-symmetry of formula 3. The present invention also provides an application of a catalyst formed by coordination of the diphenylamine-linked chiral bis(oxazoline) ligand without C.sub.2-symmetry with copper salt, zinc salt, nickel salt, iron salt or rhodium salt, in an asymmetric catalytic reaction. ##STR00001##