Abstract
Elemental sulphur and unsaturated phytyl derivatives have been shown to react in the presence of trimethylamine at low temperature (45°C) to produce two C
20 isoprenoid thiophenes which have been reported previously in unconsolidated sediments. The type of reaction involved, which takes place under mild hydrous conditions with common sedimentary species, is, therefore, of significance for the formation of thiophenes during early diagenesis.