Process for making 2-aminomethyl-1, 4-diaminobenzene and its salts and compositions and methods for dyeing keratin fibers using same
申请人:Wella Aktiengesellschaft
公开号:US06461390B1
公开(公告)日:2002-10-08
A process is described for making 2-aminomethyl-1,4-diaminobenzene, or a physiologically compatible salt of 2-aminomethyl-1,4-diaminobenzene, of formula (I):
wherein n is a number from 0 to 3 and HX represents an inorganic or organic salt. In this process 2-(N-acylaminomethyl)-4-nitrophenol is first reacted with a halogen acetamide to form 2-(2-N-acylaminomethyl-4-nitrophenoxy)acetamide, which is then converted to 2-(N-acylaminomethyl)-4-nitroaniline. Subsequently the 2-(N-acylaminomethyl)4-nitroaniline is reduced to form 1,4-diamino-2-(N-acylaminomethyl)benzene, which is then deacylated by adding hydrochloric acid in a sufficient amount so that 1,4-diamino-2-aminomethylbenzene trihydrochloride is formed. Then the trichloride is converted to the free base form, 1,4-diamino-2-aminomethylbenzene, or to another salt of 1,4-diamino-2-amino-methylbenzene when n≠0 with the proviso that if n=3 HX is not hydrochloric acid. Compositions and methods for dyeing keratin fibers using the compounds of formula I are also described.
描述了一种制备2-氨甲基-1,4-二氨基苯或2-氨甲基-1,4-二氨基苯的生理兼容盐的过程,其化学式为(I):其中n是从0到3的数字,HX代表无机或有机盐。在这个过程中,首先将2-(N-酰胺基甲基)-4-硝基苯酚与卤代乙酰胺反应,形成2-(2-N-酰胺基甲基-4-硝基苯氧基)乙酰胺,然后将其转化为2-(N-酰胺基甲基)-4-硝基苯胺。随后,将2-(N-酰胺基甲基)4-硝基苯胺还原,形成1,4-二氨基-2-(N-酰胺基甲基)苯,然后通过加入足够量的盐酸去酰基化,形成1,4-二氨基-2-氨甲基苯三盐酸盐。然后将三盐酸盐转化为游离碱形式,1,4-二氨基-2-氨甲基苯,或者当n≠0时,转化为1,4-二氨基-2-氨基甲基苯的另一种盐,但如果n=3,则HX不是盐酸。还描述了使用化学式I化合物染色角蛋白纤维的组合物和方法。