| 摘要 |
<p>The invention relates to a process for the preparation of S(+)-6-methoxy- alpha -methyl-2-naphthalene-acetic acid by resolution of R,S-6-methoxy- alpha -methyl-2-naphthalene-acetic acid. According to the invention R,S-6-methoxy- alpha -methyl-2-naphthalene-acetic acid and R(-)-2-amino-1-butanol are dissolved in water at 40-60 DEG C. Then the solution thus obtained is cooled to 25-35 DEG C. Subsequently the obtained solution is grafted with a salt of S(+)-6-methoxy- alpha -methyl-2-naphthalene-acetic acid and R(-)-2-amino-1-butanol, further it is cooled to 5-15 DEG C. The thereby formed crystals are separated from the solution and washed with water and subsequently hydrolyzed by adding a strong acid, whereby S(+)-6-methoxy- alpha -methyl-2-naphthalene-acetic acid crystallizes and the obtained crystals are separated from the mother lye and the R(-)-6-methoxy- alpha -methyl-2-naphthalene-acetic acid present in the crystallization-mother lye is racemized by heating, which racemate solution can be reused as starting material.</p> |
