Hydroxy-indanyl-propylamine prepn. - using (2)-indanone-cyanhydrin with hydroxyl group protected by reaction with vinyl alkyl ether

摘要

1-(2-Hydroxy-2-indanyl)propylamine is prepd. from 2-indanone cyanhydrin in which the hydroxyl group is protected by a vinyl alkyl ether group of formula RO.CH:CH2 (where R is 1-6C alkyl), by addition of an ethylmagnesium halide hydrolysing the reaction product and hydrogenating the imine to an amine group and removing the protective group. The product, an anorectic and lipolytic agent, is made in 55-60% yield without any increase in cost of raw materials. Typically, the cyanhydrin is protected by reaction with vinyl ethyl ether in THF, the solvent is evapd. and the residue in toluene is treated with ethylmagnesium bromide in THF, and the product hydrolysed. The imine in toluene is hydrolysed with LiAlH4 and converted into the hydrochloride (yield 57% of overall).