A compound of the formula 1 in which the dotted line represents a single double bond in either the 4a,8a- or the 4,4a-position. The formula covers the compounds 1,2,8,8-tetramethyl-1,2,3,4,5,6,7,8-octahydro-naphthalene-2-carbonitrile and (1RS,8aSR)-1,2,8,8-tetramethyl-1,2,3,5,6,7,8,8a-octahydro-naphthalene-2-carbonitrile. These are useful as intermediates in the preparation of desirable fragrance molecules.
