Author(s): Braden Nelson
Mentor(s): Nathan S. Werner
Institution SUU
The stereocontrolled palladium-catalyzed Suzuki-Miyaura cross-coupling reaction of (E)-2-phenylethenylboronic acid pinacol ester with aryl chlorides to produce (E)-stilbene derivatives was studied. (E)-2-Phenylethenylboronic acid pinacol ester was synthesized by 9-borobicyclo[3.3.1]nonane (9-BBN) catalyzed hydroboration reaction of phenylacetylene with pinacolborane. The reaction parameters of organometallic donor stoichiometry, ligand, solvent and base were evaluated to maximize the yield of cross-coupling product. The scope of compatible aryl chlorides was then evaluated under the optimized reaction conditions. Six aryl chlorides bearing various electron-withdrawing, electron-donating, and a nitrogen-containing heterocyclic aryl chloride were found to undergo facile cross-coupling in 38-87% isolated yield.