%0 Journal Article
%T Iodination of vanillin and subsequent Suzuki-Miyaura coupling: two-step synthetic sequence teaching green chemistry principles
%A Beau C. Gilles
%A Grant W. Fahnhorst
%A James J. Palesch
%A Jane E. Wissinger
%A Jared Chycota
%A Moriana K. Haj
%J Green Chemistry Letters and Reviews
%D 2019
%R https://doi.org/10.1080/17518253.2019.1609603
%X ABSTRACT A two-step synthetic sequence was developed for the undergraduate organic chemistry laboratory using vanillin as the starting material. The multi-step synthesis was designed to replace two traditional experiments teaching electrophilic aromatic substitution and carbon¨Ccarbon bond forming chemistries with greener transformations. Vanillin is iodinated using Oxone£¿ and potassium iodide in refluxing water, and students are tasked with determining the position of aromatic substitution using 1H NMR spectroscopy. The tan, shiny, pleasant-smelling iodovanillin is subsequently used in an aqueous Suzuki-Miyaura reaction with para-methylphenylboronic acid; strategically chosen to afford a second instructive 1H NMR spectrum. Both conventional heating and microwave conditions can be employed for the palladium-catalyzed reaction. This synthetic sequence, successfully performed over multiple semesters by hundreds of students, models green chemistry principles through the use of a potentially renewable feedstock and safer reagents, the choice of water as a safer reaction solvent, and the employment of a catalytic reaction. Additionally, the sequence minimizes waste in teaching labs through use of an intermediate product. GRAPHICAL ABSTRAC
%U https://www.tandfonline.com/doi/full/10.1080/17518253.2019.1609603