Reductions and Revisions

My most recent work in the lab has been to reduce the an ester to a primary alcohol. In other words, we’re attempting to alter the oxidation state of a particular portion of the compound. To this end, we’re using the reducing agent diisobutylaluminum hydride, or Dibal-H, for the reaction. This reagent is a bit dangerous to work with it, because it is pyrophoric, meaning it spontaneously ignites in air at room temperature. This requires that we make a 1.0 molar solution of Dibal-H in a solvent, which will be added to the starting material.

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Week 9 update

It’s the end of week 9 and it’s certainly hard to believe how quickly the summer is passing. This research session has certainly had its ups and downs. The saponification/esterification sequence that previously plagued my chemical synthesis has become facile. My latest run had an overall yield of 71% over 3 steps, which is an improvement over the 65% yield that was achieved in the first generation synthesis. The following reduction, though, has proved difficult. After doing the reaction three times, I’ve maintained consistent results but the yields have been very low (20-30%).  it’s been a true test of using all available skills and techniques to learn how to improve a reaction. We’ve currently devised a new plan to circumvent the alcohol with a new scheme. Unfortunately, this new plan somewhat dampens the efforts and progress we made to get to that point, but it appears to be a necessary solution.

Setting a pace

It’s hard to believe that over two whole weeks of summer research are already completed. The pace of the summer is certainly different than that of the academic term. Running multiple reactions and purifying them can be easily accomplished. Idleness, though, is not always inescapable. It’s always prudent to play your day beforehand, a point that my adviser has stressed to his students. A busy or malfunctioning instrument can make you rethink those characterizations you were intending to knock out, the column that needs to be done, etc.

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