反应详情

Commercially available dimethyl fluoromalonate (1) (or the diethyl ester) is condensed with guanidine hydrochloride (2) to yield 4,6-dihydroxy-5-fluoro-2-pyrimidineamine (3). This product (3) was converted to the dichloride (4) with POCl3 /2-picoline. Introduction of the 4-amino group was carried out undersealed tube conditions to give (5). Oxidation of (5) with MCPBA formed the N-oxide (6) which was smoothly converted to the 5-fluoro minoxidil with piperidine in refluxing ethanol.