The optimized preparation of an array of brominated, chlorinated, and iodinated oxime-containing ester derivatives of L-tyrosine is reported. The use of these halogenated precursors in the total synthesis of natural and non-natural products of biological relevance has been a focus of this research group. Moreover, halogenation of a phenol opens the door to the regioselective formation of C-C bonds through palladium-catalysis and custom substitution of phenols with heterocycles. Oxime-containing L-tyrosine methyl ester and L-tyrosine tert-butyl ester were used as templates in these halogenation reactions, as shown in the Figure provided. Each dihalogenated product was formed via an oxidative dearomatizing spirocyclization process. The monohalogenation, dihalogenation, and hetero-dihalogenation processes featured efficient purification steps unique to each product type. These products were prepared in high yield and purity with all of the products being isolated in at least 90% purity with most yields in excess of 75%. A streamlined preparation of the products of the L-tyrosine methyl ester on large scale has also been performed and developed.
University / Institution: Utah Valley University
Format: In Person
SESSION C (1:45-3:15PM)
Area of Research: Science & Technology
Faculty Mentor: Steve Chamberland