Preparation method of chiral hexahydropyrroloindole compound

The invention relates to a preparation method of a chiral hexahydropyrroloindole compound. A catalytic amount of cuprous salt and chiral diphosphine ligand are first stirred to react in organic solvent under argon atmosphere and room temperature for 20 minutes, and are then sequentially added with C(3)/C(2)-substituted indole and substituted N-sulphonyl ethylene imine to react under certain temperature, and thereby the chiral hexahydropyrroloindole compound is obtained. The reaction process is tracked by thin-layer chromatography (TLC), ethyl acetate is adopted for extraction, anhydrous sodium sulfate is adopted for drying, pressure is reduced to remove solvent, so that a crude product is obtained, mixed solvent in which the volume ratio of petroleum ether containing 0.5v percent of triethylamine and ethyl acetate is 10 to 40:1 is adopted as developing solvent, the product is obtained by column chromatography separation, the enantiomeric excess of the product is determined by high-performance liquid chromatography on a chiral chromatographic column, and the molar ratio of the cuprous salt, the chiral diphosphine ligand, the C(3)-substituted indole and the substituted N-sulphonyl ethylene imine is 5:3:100:220. Compared with the prior art, the method can prepare the chiral hexahydropyrroloindole compound with a catalytic asymmetric [3+2] cycloaddition method, and has the following characteristics: the reaction materials are simple and easy to obtain, the reaction conditions are mild, product structure types are rich, and yield and stereoselectivity are high.