Synthesis of alkylated phenanthrenes

Abstract

This thesis captures the process of synthesizing gram quantities of the compounds 2,3-dimethylphenanthrene (7a), 2,7-dimethylphenanthrene (7b) and 1,7-dimethylphenanthrene (7c) to be used in the EGGTOX project. The EGGTOX project is a fish exposing experiment by Institute of Marine Research. The product 1,9-dimethylphenanthrene (8d) will be delivered after a request by J. H. Christensen in Section for Environmental Chemistry and Physics at University of Copenhagen, Denmark. The 8d product was made by Kumada coupling, which was an immediate success. Next attempt was to make 2,3,9-trimethylphenanthrene (8e), which might have been successfully made, but needs purification to get good analysis of the new compound. Another experiment to make 1-methyl-9-vinylphenanthrene (8f) was unsuccessful. The chemical route for the project was a general regiospecific route to produce alkylated phenanthrenes, as shown in the scheme below. The products were made by Directed ortho Metalation (DoM), Suzuki-Miyaura cross coupling and Directed remote Metalation (DreM). The target molecules were obtained in total yields over 6 steps as listed in the table. The compounds in this thesis made for the EGGTOX project were triflated and deprotected, while the rest went through Kumada Coupling, resulting in a new R group to a specific phenanthrene. Further experiments in adding vinyl group by Kumada Coupling may provide a new way to build substituted PAHs.