Piperazine → 2-(Piperazin-1-yl)-1,3-benzoxazole

Participants

Reaction Steps

A 3.07 g portion of 2-chlorobenzoxazole was dissolved in 10 ml of dichloromethane. Under cooling with ice, to this was added dropwise 3.45 g of anhydrous piperazine which has been dissolved in 30 ml of dichloromethane, followed by 1 hour of reaction. The reaction solution was concentrated under a reduced pressure, and the resulting residue was purified by a silica gel column chromatography (dichloromethane:methanol=20:1), followed by concentration of the eluate under a reduced pressure. Thereafter, the resulting residue was dissolved in 30 ml of water, neutralized with 1N hydrochloric acid, extracted with dichloromethane, washed with water, dehydrated with Na2SO4 and then concentrated under a reduced pressure to obtain 1.77 g of 2-(1-piperazinyl)benzoxazole.

Provenance & Evidence