摘要 |
An efficient and industrially applicable process for preparing aclidinium bromide of formula I, comprising the following steps a) preparation of the quinuclidinyl ester by transestenfication of methyl di(2-thienly)giycolate with R-(-)-3-quinuclidinol in the presence of a sterically hindered base in an inert solvent; b) isolation of the quinuclidinyl ester; and c) quaternization of the quinuclidinyl ester by 3-phenoxypropyl bromide in a suitable solvent. |