Abstract: The present invention relates to 2-isopropoxy-5-methyl-4-(piperidin-4-yl) aniline dihydrochloride monohydrate and a preparation method of the same. The 2-isopropoxy-5-methyl-4-(piperidin-4-yl) aniline dihydrochloride monohydrate has a very good crystal form and is well suitable for recrystallization purification; further, the effect of impurity removal effect is very good, and any single impurity can be controlled less than 0.1%.

Abstract: The present invention relates to 2-isopropoxy-5-methyl-4-(piperidin-4-yl) aniline dihydrochloride monohydrate and a preparation method of the same. The 2-isopropoxy-5-methyl-4-(piperidin-4-yl) aniline dihydrochloride monohydrate has a very good crystal form and is well suitable for recrystallization purification; further, the effect of impurity removal effect is very good, and any single impurity can be controlled less than 0.1%.

Abstract: A process for preparing a siloxane compound comprising a 2-hydroxyphenyl benzotriazole function which comprises at least one step in which a reaction for hydrosilylation of a compound 2-hydroxyphenyl benzotriazole comprising a substituent having a terminal double bond with a siloxane compound comprising an SiH function is carried out in the presence of a catalyst and of at least one volatile organic solvent corresponding to one of formula (VII) or (VIII). in which R4 and R5, which may be identical or different, represent a linear or branched C1-C4 alkyl radical, with the proviso that the sum of the carbons of R4 and R5 is less than or equal to 6; y is and integer between 1 and 3; R6 which may be identical or different, are linear or branched C1-C3 alkyl radicals, with the proviso that the sum of the carbons of R6 is less than or equal to 6 is disclosed.

Abstract: The chiral compound S-5-substituted-N-2?-(thienyl-2-yl-)ethyl-tetralin-2-amine or its chiral acid salts and preparation method thereof are disclosed, and the method for preparing Rotigotine by using the chiral compound is also disclosed. Racemic 5-substituted-N-2?-(thien-2-yl-)ethyl-tetralin-2-amine (compound 1) is resolved by using a conventional chiral acid to obtain an optically pure chiral acid salt of S-5-substituted-N-2?-(thien-2-yl-)ethyl-tetralin-2-amine, which is then dissociated to obtain S-5-substituted-N-2?-(thien-2-yl-)ethyl-tetralin-2-amine (compound 2). The compound 2 or chiral acid salt thereof is alkylated and deprotected to produce rotigotine (compound 5).

Abstract: A process for preparing a siloxane compound comprising a 2-hydroxyphenyl benzotriazole function which comprises at least one step in which a reaction for hydrosilylation of a compound 2-hydroxyphenyl benzotriazole comprising a substituent having a terminal double bond with a siloxane compound comprising an SiH function is carried out in the presence of a catalyst and of at least one volatile organic solvent corresponding to one of formula (VII) or (VIII). in which R4 and R5, which may be identical or different, represent a linear or branched C1-C4 alkyl radical, with the proviso that the sum of the carbons of R4 and R5 is less than or equal to 6; y is and integer between 1 and 3; R6 which may be identical or different, are linear or branched C1-C3 alkyl radicals, with the proviso that the sum of the carbons of R6 is less than or equal to 6 is disclosed.

Abstract: The chiral compound S-5-substituted-N-2?-(thienyl-2-yl-)ethyl-tetralin-2-amine or its chiral acid salts and preparation method thereof are disclosed, and the method for preparing Rotigotine by using the chiral compound is also disclosed. Racemic 5-substituted-N-2?-(thien-2-yl-)ethyl-tetralin-2-amine (compound 1) is resolved by using a conventional chiral acid to obtain an optically pure chiral acid salt of S-5-substituted-N-2?-(thien-2-yl-)ethyl-tetralin-2-amine, which is then dissociated to obtain S-5-substituted-N-2?-(thien-2-yl-)ethyl-tetralin-2-amine (compound 2). The compound 2 or chiral acid salt thereof is alkylated and deprotected to produce rotigotine (compound 5).