Significance: (–)-Berkelic acid was isolated from an extremophilic Penicillium species in 2006 by Stierle and co-workers from the surface waters of Berkeley Pit Lake, Butte, Montana, USA. This natural product has been the subject of much interest to the synthetic community due to its unusual structure and diverse range of biological activity. Whilst this is not the first synthesis of this natural product, this route is shown to be highly scalable, with each step leading to the (–)-berkelic acid methyl ester performed on >1 g scale. Due to the reported instability of (–)-berkelic acid, the last step was conducted on a 50 mg scale.