Two routes to the unusual 12-membered unsaturated benzolactone of the highly cytotoxic marine metabolites the salicylihalamides are presented. The first involves an RCM step to construct the C9 C10 alkene bond and this provided the model macrolactones 9 and 10 in a ratio of 77:23, respectively. An alternative route involved a Stille coupling to construct the C8 C9 bond followed by a macrolactonization to give the lactones 9 and 10 in a ratio of 96:4.