反应详情

tert-butyl 4-formylpiperidine-1-carboxylate 4a was reacted with aqueous glyoxal in the presence of aqueous ammonium hydroxide in methanol to give tert-butyl 4-(1H-imidazol-2-yl)piperidine-1-carboxylate 4b, which was bromined to afford tert-butyl 4-(4-bromo-1H-imidazol-2-yl)piperidine-1-carboxylate 4c. 4c was alkylated with 2-(2-bromoethoxy)tetrahydro-2H-pyran, followed by removal of THP group under acidic condition to yield tert-butyl 4-(4-bromo-1-(2-hydroxyethyl)-1H-imidazol-2-yl)piperidine-1-carboxylate 4d. Suzuki coupling was performed with bromide intermediate 4d to afford 4e. 4e was reacted with methanesulfonyl chloride or 4-methylbenzenesulfonyl chloride, followed by quenching with amine afforded 4f, which was treated with hydrogen chloride in methanol or trifloruoacetic acid in DCM to provide the amine intermediates 4g.

1. customfollowed by removal of THP group under acidic condition