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

Participants

Reaction Steps

3-Chloro-1,2-benzisoxazole reacted with excess piperazine in the presence of pyridine to provide 3-(piperazin-1-yl)benzo[d]isoxazole (3A) in 76% yield. Reductive amination of compound (3A) with 2-carbomethoxy 2-methyl propionaldehyde gave alkylated piperazine (4A), which was purified over silica gel. Basic hydrolysis of the methyl ester of (4A) in aqueous ethanol followed by acidification gave the carboxylic acid (1) as the mono-HCl salt.

Provenance & Evidence