Compound is prepared through the following sequence: The condensation of 1-methyl-7-methoxy-2-tetralone (I) with 1,5-dibromopentane (A) by means of NaH or potassium tertbutylate affords 1-(5-bromopentyl)-1-methyl-7-methoxy-2-tetralone (II); this product is cyclized with NaH to give 5-methyl-3-methoxy-5,6,7,8,9,10,11,12-octahydro-5,11-methanobenzocyclodecen-13-one (III). The ketone (III), by reaction with hydroxylamine hydrochloride in pyridine, is converted into its oxime (IV), which is reduced with H2 over Raney-Ni to a mixture of isomeric amines that were separated by crystallization of the HCl salts giving 5alpha-methyl-3-methoxy-5,6,7,8,9,11alpha,12-octahydro-5,11-methanobenzocyclodecen-13beta-amine (V), which is finally submitted to cleavage with concentrated HBr.