Allyl bromide → 7-allyl-8,9-dihydro-10-methyl-7-[(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 (395 mg) in tetrahydrofuran (5 ml) at -70° C. under a nitrogen atmosphere was added 1.64 M butyllithium in hexane (2.62 ml). After being stirred at the same temperature for 20 minutes, the mixture was treated with a solution of 8,9-dihydro-10-methyl-7-[(5-methyl-1-trityl-1H-imidazol-4-yl)methyl]pyrido[1,2-a]indol-6(7H)-one (1.61 g) in tetrahydrofuran (5 ml) over 15 minutes. The mixture was stirred at -65° C. for 30 minutes and at -30~-40° C. for 30 minutes and a solution of allyl bromide (363 mg) in tetrahydrofuran (5 ml) was added dropwise at -65° C. over 10 minutes. After the mixture was stirred at -65° C. for 1 hour, at -20° C. for 1 hour and at ambient temperature for 1 hour. The resultant mixture was washed with water (10 ml ×2) and brine, dried over anhydrous magnesium sulfate and evaporated in vacuo. Purification of the residue with silica gel column chromatography (5% ethyl acetate-chloroform) gave 7-allyl-8,9-dihydro-10 -methyl-7-[(5-methyl-1-trityl-1H-imidazol-4-yl)methyl]pyrido[1,2-a]indol-6(7H)-one (1.15 g).

Provenance & Evidence