Oxalic Acid → 8,9-dihydro-7-[(hydroxy)(5-methyl-1-trityl-1H-imidazol-4-yl)methyl]pyrido[1,2-a]indol-6(7H)-one

Participants

Reaction Steps

To a solution of diisopropylamine (658 mg) in tetrahydrofuran (8 ml) at -70° C. under nitrogen atmosphere was added 1.64M butyllithium in hexane (3.96 ml). After being stirred at the same temperature for 20 minutes, the mixture was treated with a solution of 8,9-dihydropyrido[1,2-a]indol-6(7H)-one (1.21 g) in tetrahydrofuran (12 ml) over 15 minutes. The mixture was stirred at -70° C. for 30 minutes, and a solution of 5-methyl-1-trityl-1H-imidazole-4-carbaldehyde (2.29 g) in tetrahydrofuran (20 ml) was added dropwise over 20 minutes. After the mixture was stirred at -70° C. for further 60 minutes and at ambient temperature for 2 hours, it was diluted with water and neutralized with an aqueous solution of oxalic acid. Separated organic layer was washed with brine, dried over anhydrous magnesium sulfate, and evaporated in vacuo to give 8,9-dihydro-7-[(hydroxy)(5methyl-1-trityl-1H-imidazol-4-yl)methyl]pyrido[1,2-a]indol-6(7H)-one (2.21 g) as an amorphous powder. The product was a mixture of two diastereoisomers.

Provenance & Evidence