Abstract: A method for preparing compound 1 and compound 2 having a structure as shown below, the method includes the following steps: 1) subjecting 2,3-dihydrobenzofuran-7-amine as a raw material to a selective-dibromination with a brominating reagent to obtain 4,6-dibromo-2,3-dihydrobenzofuran-7-amine; 2) subjecting 4,6-dibromo-2,3-dihydrobenzofuran-7-amine obtained in the step 1) to Sandmeyer reaction for chlorination to obtain 4,6-dibromo-7-chloro-2,3-dihydrobenzofuran; 3-1) selectively debrominating from 4,6-dibromo-7-chloro-2,3-dihydrobenzofuran obtained in the step 2) using a strong base, and then adding a formylation reagent to obtain compound 1; 3-2) selectively debrominating from 4,6-dibromo-7-chloro-2,3-dihydrobenzofuran obtained in the step 2) using a strong base, and then reacting with 4-cyclopropyl benzaldehyde to obtain compound 2.

Abstract: A method for preparing (2S,3S)-3-amino-bicyclo[2.2.2]octane-2-carboxylate is in the field of pharmaceutical intermediate synthesis. The method uses 3-carbonyl-bicyclo[2.2.2]octane-2-carboxylate as the starting material and performs reductive amination, alkalinity configuration flip, and hydrogenation to remove the protecting group in sequence to obtain the target product. This synthesis method of (2S,3S)-3-amino-bicyclo[2.2.2]octane-2-carboxylate is characterized by a novel route, mild reaction conditions and low cost, with a yield of more than 65%.