Synthesis method of stepholidine or derivative optical isomer thereof and intermediate thereof

The invention belongs to the fields of pharmaceutical chemistry and asymmetric synthesis chemistry, in particular relates to chemical synthesis method of natural product stepholidine with schizophrenia resistant activity or derivative optical isomer thereof, especially chemical synthesis method of L-stepholidine or derivative optical isomer thereof. The invention aims at providing a chiral synthesis method capable of synthesizing chemically pure stepholidine or derivative optical isomer thereof. The method includes that a chiral carbon construction is built by asymmetrical catalytic hydrogenation participated by chiral metal catalyst, and in the preparation process, 3, 4-dihydro-isoquinoline compound shown as the following formula I is synthesized, and the compound can be used for preparing chemically pure stepholidine or derivative optical isomer thereof.