Faculty Mentor: David Hunt
Students: John Farrokh
Benzo-fused 7-membered heterocyclic ketones have been shown to possess pharmacological activity. The goal of our project is to develop a new method of synthesizing these compounds. Starting materials were typically prepared by reacting a compound unique to each reaction with 2-cyanobenzylbromide.
The reaction utilized to prepare these products entailed the formation of a N-lithioimine salt by reacting the starting material with n-butyllithium at -78 oC followed by an acidic work-up and extraction.
Using this methodology, the compound above and several analogous compounds have been successfully prepared, isolated and characterized. Of particular interest is the thioether formed by using sulfur as the heteroatom instead of oxygen as it behaves differently than the other analogues. When treated with 2.0 equivalents of n-BuLi or greater, the reaction favors the formation of the butylated side products shown below. Preparing the reaction with 1.0 equivalents of n-BuLi forms the desired product exclusively, but does not lead to a complete reaction (~40%). The effects of using t-BuLi as a substitute for n-BuLi to eliminate alkylation have yet to be determined.