Regiospecific synthesis of disubstituted phenanthrenes

Abstract

As the Norwegian oil fields mature, the wells produce more water. This produced water containing a diverse mixture of dissolved PAHs is eventually released to the environment. A major part of these discharges are alkylated PAHs, but due to lack of pure compounds the e↵ect of alkylated PAHs have been scarcely studied. Studies on the metabolism of monomethylated phenanthrenes by the benthic invertebrate Nereis diversicolor gave di↵erent product distributions depending on the position of the substituent. Now various dimethylated phenanthrenes are needed for further environmental studies. In this thesis a selection of dimethylated phenanthrenes has been prepared using a combination of Directed ortho-Metalation (DoM), Suzuki-Miyaura cross coupling, and Directed remote-Metalation (DreM). 2,7-, 2,3-, 1,7- and 2-6-dimethyl-9-phenanthrol have been made into the corresponding phenanthrenes by a simple Pd-catalyzed hydrogenolysis of the triflate protected alcohol. The single isomers resulting from this route provides the dimethylphenanthrenes in high purity and in gram quantities,