New telescoping synthesis of 2-methoxymethyl-p-phenylenediamine

摘要

A telescoping process for the preparation of 2-methoxymethyl-p-phenylenediamine, a cosmetically acceptable salt thereof, or mixture thereof. The process according to the present invention is a particularly cost effective process in that it avoids sophisticated chemical steps which requires special equipment or expensive catalysts and in that it comprises a recycling step of one of the starting materials, namely 2-methoxymethylaniline.

主权项

1. A telescoping process for the preparation of 2-methoxymethyl-p-phenylenediamine (I), a cosmetically acceptable salt thereof, or mixture thereof comprising the steps of:
a) synthesizing the intermediate 2-(methoxymethyl)-4-{3-[2-(methoxymethyl)phenyl]triaz-1-en-1-yl}aniline (IV) via diazotation using 2-methoxymethylaniline (II) to obtain the intermediate of formula (III) followed by diazo coupling between the intermediate of formula (III) and 2-methoxymethylaniline (II): b) synthesizing the intermediate 2-(methoxymethyl)-4-{(E)-[2-(methoxymethyl)phenyl]diazenyl}aniline (V) via rearrangement of the intermediate 2-(methoxymethyl)-4-{3-[2-(methoxymethyl)phenyl]triaz-1-en-1-yl}aniline (IV) obtained in step a): c) synthesizing 2-methoxymethyl-p-phenylenediamine (I) and 2-methoxymethylaniline (II) via hydrogenation of the compound of formula (V):