As week three comes to a close, the Orgo I students finished up their last experiments and checked out of lab. The foundations of organic structures and configurations have already been established in the first two weeks of class leading up to the final full week where concepts are expanded to reagents and mechanisms of reactions. Learning the multitude of reagents and understanding mechanisms is challenging and overwhelming at times, but allowing these two concepts to become a way of thinking instead of memorization is one of the keys to success in organic chemistry (along with hard work and plenty of chemistry jokes of course). With the introduction of mechanisms and reagents, students are now able to propose and conduct different synthesis routes to produce a desired final compound, which is exactly what occurred in lab. The lab this week was spread out over two days, with each day dedicated to one of the two steps of the synthesis of diphenylacetylene, a compound containing two phenyl groups attached by an alkyne or carbon-carbon triple bond.
Abstracts of Articles on Organic Synthesis - Organic chemistry
After students isolated stilbene dibromide using vacuum filtration, the samples were analyzed using Nuclear Magnetic Resonance (NMR). The NMR instrument, by far my favorite form of analysis in organic chemistry, detects signals of different atom isotopes depending on the specifications of the study being run. This time, everyone ran a proton NMR, which detects the spin signals (up or down) given off by neighboring protons. Where the signal for a proton appears on the spectrum depends on the electronegativity of the surrounding atoms.
Although this blog was filled with quite a bit of organic chemistry jargon, I hope I made it accessible to everyone, even those students who took chemistry in high school and decided it was not their cup of tea. Hopefully the joy of accomplishing a synthesis or understanding a new concept was expressed through the pictures and my rambling about the procedure. If you can’t tell, I find the whole synthesis process quite fascinating. Stay tuned for Organic Chemistry jeopardy (yes it exists and is the only kind of jeopardy where I can actually answer any of the questions) and a wrap up of the final three days of class!