Intermediate for synthesizing paroxetine, method for preparing the same, and uses thereof

A method of preparing a compound of formula III below,

• obtained by reacting a compound of formula I with a compound of formula II in the presence of an organic base under the catalysis of a complex formed from a chiral amine oxide L and a rare-earth metal compound Ln(OTf)3:
• wherein R1 is alkyl, phenyl or benzyl, preferably C1-C6 alkyl, phenyl or benzyl;
• R2, R3 and R4 are each independently C1-C6 alkyl or C6-C10 aryl;
• the chiral amine oxide L has the following structure:
• wherein n=1, 2;
• and R=Ph—, 2,6-Me2C6H3—, 2,6—Et2C6H3—, 2,6-iPr2C6H3—, Ph2CH—;
• and
• Ln in the rare-earth metal compound Ln(OTf)3 represents a lanthanide metal selected from La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu.