2-((Dimethylamino)-methyl)-1-(3-methoxyphenyl)-cyclohexanol preparation, by Grignard reaction in presence of lithium salt and dialkoxyalkane to give high yield of the analgesic trans-isomer tramadol

摘要

The preparation of 2-((dimethylamino)-methyl)-1-(3-methoxyphenyl)-cyclohexanol (I) by Grignard reaction of 2-((dimethylamino)-methyl)-cyclohexanone (II) with the Grignard compound (III) of 3-bromoanisole is carried out in a solvent in presence of an inorganic lithium salt (IV) and an alpha,omega-dialkoxyalkane (V).