Intuitively, one might expect the phenyl groups to attach to the outside edge of the phenanthrene, away from the bay region, where there is more space. However the researchers have managed to find the perfect set of reaction conditions – including temperature, solvent, and type of Lewis Acid – to enable most phenyl groups to attach in the bay region and form the most hindered product.
Dr Itami hopes that this new simple synthesis will provide access to a host of useful molecules in future. "Due to the structural variety, good optical and electronic properties, nonplanar phenanthrenes will serve as useful building blocks for the synthesis of better organic materials, such as organic light-emitting materials and circularly polarized luminescent materials. Moreover, phenanthrene derivatives exhibit a wide range of biological activities, we hope more bioactivity of these twisted phenanthrenes will be discovered in the near future."
This article is free to read in our open access, flagship journal Chemical Science: Kenichiro Itami et al., Chem. Sci., 2019, Advance Article. DOI: 10.1039/C9SC00334G. You can access our 2019 ChemSci Picks in this article collection.