A method of making spirogalbanone includes the steps of: (a) subjecting ethynylspirodecanol to a Rupe rearrangement to give a compound of the formula I (b) converting the compound of (a) to a C1-C4 alkyl acetal; (c) subjecting the acetal to a trans-acetalisation reaction with allyl alcohol in the presence of a mild acid catalyst; (d) heating the product of (c) in the presence of an acid catalyst to give an allylenolether; and (e) subjecting the product of (d) to a Claisen rearrangement to give spirogalbanone. The method affords an easier and more efficient method of preparation.