5-氟-吲哚-2-酮的合成

Synthesis of 5-fluoro-1,3-dihydro-indol-2-ono

优化5-氟-吲哚-2-酮(3)的合成工艺,提高其收率。首先以4-氟苯胺为起始原料,与水合氯醛及盐酸羟胺作用生成对氟异亚硝基乙酰苯胺(1),然后在浓硫酸作用下进行环合形成化合物5-氟靛红(2),最后经Wolff-Kishner-黄鸣龙反应得到5-氟-吲哚-2-酮(3),总收率为66%。本法具有原料廉价易得,反应条件温和,操作简便,收率高等特点。

In order to improve the synthetic procedure of 5-fluoro-1,3-dihydro-indol-2-ono （ 3 ）. First, with the 4-fluoroaniline as the starting materials, react with chloral hydrate and hydroxylamine hydrochloride to synthesis 5-fluroisonitrosoacetanilide （ 1 ）. Then 5-fluroisatin （2） was synthesized from （ 1 ） by cyclization reaction in the presence of cone. H2SO4. Finaly,5-fluoro-1,3-dihydro-indol-2-ono （3） was prepared by Wolff-Kishner-HuangMinlong reaction of （2）. The total yield is 66%. The procedure developed has several advantages：such as cheap reagents,facile reaction conditions, convenient operation and high yield.