Carmen Sivakumaren collected these colorful solutions in test tubes as they flowed off a silica gel column. The graduate student at Harvard University and Dana-Faber Cancer Institute was looking for a specific product of a nucleophilic substitution reaction she ran between an indole and a trichloropyrimidine. When chemists run a reaction mixture through a silica column, molecules exit the column at different times depending on their polarity, allowing them to isolate their desired product. Because Sivakumaren’s reaction produced strongly colored by-products, she could spot groups of test tubes that held different by-products with the naked eye. Eventually, Sivakumaren found her product, which ironically was a white solid.
Submitted by Carmen Sivakumaren
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