Process for the preparation of high purity 2,4'-dimethyl-3-piperidinopropyrophenone (tolperisone), pharmaceutical compositions containing this, as well as active ingredient formulations containing tolperisone
Process for the preparation of high purity 2,4'-dimethyl-3-piperidinopropyrophenone (tolperisone), its pharmaceutically acceptable salts, hydrochlorides and hydrates, wherein 4-methylpropiophenone is reacted ** Formula ** with piperidine hydrochloride * * Formula ** and 1,3-dioxolane ** Formula ** in the presence of one or more acids as catalyst and crude product of tolperisone is filtered off in free form or in the form of its pharmaceutically compatible hydrochlorides, hydrates and addition salts after cooling the reaction mixture, and in which the proportion of 2-methyl-1- (4-methylphenyl) propenone (4-MMPPO) ** Formula ** characterized in that by recrystallization is reduced by recrystallization of the crude tolperisone product Recrystallization of the crude tolperisone product is added an acid and the proportion of 2-methyl-1- (4-methylphenyl) propenone (4-MMPPO) is reduced to less than 10 ppm with respect to 100% by weight of crude tolperisone product .Procedimiento para la preparación de 2,4'-dimetil-3-piperidinopropiofenona (tolperisona) de alta pureza, sus sales, clorhidratos e hidratos farmacéuticamente aceptables, en el que se hace reaccionar 4- metilpropiofenona**Fórmula** con clorhidrato de piperidina**Fórmula** y 1,3-dioxolano**Fórmula** en presencia de uno o varios ácidos como catalizador y se separa por filtración producto bruto de tolperisona en forma libre o en forma de sus clorhidratos, hidratos y sales de adición farmacéuticamente compatibles después del enfriamiento de la mezcla de reacción, y en el que mediante recristalización del producto bruto de tolperisona se disminuye la proporción de 2-metil-1-(4-metilfenil)propenona (4-MMPPO)**Fórmula** caracterizado porque en la recristalización del producto bruto de tolperisona se añade un ácido y la proporción de 2-metil-1-(4-metilfenil)propenona (4-MMPPO) se reduce a menos de 10 ppm respecto a 100 % en peso de producto bruto de tolperisona.
