Preparation of Triphenylmethanol Grignard Reaction Experiment Procedure Introduction In this two-week experiment, triphenylmethanol will be synthesized through a Grignard reaction. The prepared Grignard reagent, phenylmagnesium bromide, will then be combined with benzophenone to form the desired triphenylmethanol product. All glassware must be extremely dry!
Students learn that even similar chemical shift patterns can be distinguished: The 5 carbons of isoamyl aclohol give rise to 4 C signals.
The 6 carbons of cyclohexane give rise to 1 C signal. This combination of H and C data allows the student to discern how Ochem lab benzophenone hydrogens are attached to each carbon signal.
Shown here is an example of a compound commonly used to rate the anti-knock properties of gasoline. Here we show examples of 2D NMR These experiments probe in more detail the magnetic interactions of the the nuclei and show the student the connections between C and H in the sample and the correlation of the magnetic fields between H on adjacent C positions.
Basically, this analysis helps one figure out the 3D structure of the molecules in the sample. This gives students the idea that the magnetic field is not just "one dimensional" and leads to a discussion of how equipment like MRI can image soft tissue which contain lots and lots of protons in water and fatty tissue in different magnetic or chemical environments in the tissue or organ.
A key part of the MRI experiment involves measuring the time it takes for protons in different chemical or magnetic environments to relax. These data ultimately produce tissue images. We can do these experiments on a more modest scale at Dulles.
From Ochem Lab Modules The NMR shows clearly how the chemical reaction changed the structure. Shown here are the H-1 and C data of a sample produced by a student lab group. This year we introduced a new extraction lab.
Students extracted piperine, a component of black pepper. The extraction uses one of the more sophisticated glassware assemblies we can do and it was one of the most challenging products to purify.
The students did an outstanding job.
The data are very nice. Benzopinacol is synthesized from a free radical coupling of benzophenone which is coaxed into an excited state by exposure to sunlight. Shown here is the 1H NMR spectrum of student produced benzopinacol.
The NMR data are relatively simple due to symmetry even though the structure is large and complex. Students produce a class of biodiesel called fatty acid methyl esters FAMEs from vegetable oil. Shown here is the C13 NMR data of the oil and biodiesel.
What is striking is that the unsaturation in the structure of the oil and biodiesel is easily detected. Further, there is evidence that the oil contains free fatty acids which will contaminate the biodiesel as soap if not carefully removed.Reduction of a ketone using sodium borohydride.
Control of a reaction by TLC Supplementary Material This work is intended to first year chemistry students and uses the easily performed reduction of benzophenone to diphenylmethanol in the presence of sodium borohydride as a starting point to introduce the control of a reaction by TLC.
Name: Chevaunne Sinclair Id Number: Course: Organic Chemistry II Lab Session: Tuesday- Thursday Lab #: 1 Chevaunne Sinclair Title: Grignard Preparation. From Ochem Lab Modules A student extracted acetyl salicylic acid from an aspirin tablet and recorded this beautiful ¹H NMR spectrum: Benzopinacol is synthesized from a free radical coupling of benzophenone which is coaxed into .
In lab today, I prepared a solution of Grignard reagent (phenylmagnesiumbromide) in anhydrous ether.
Two step reaction: Photoreduction (sunlight) of Benzophenone to Benzopinacol and Pincacol Rearrangement to the Ketone (UV spectral analysis of products; GC analysis for acetone by-product) Lab 19 Synthesis of Fragrant Esters (we’ll make a few, one of which will derive from the salicylic acid the students made in Lab 3). Carbonyl Addition Reactions Preparation and Reactivity of Grignard Reagents Luke Barone Lab Partner: Nicki Thursday Night, Instructor: Feng Lang. Grignard Synthesis of Triphenylmethanol Lab Report. The Grignard Synthesis of Triphenylmethanol Organic Chemistry Lab II March 19, Abstract The purpose of this experiment was to synthesize the Grignard reagent, phenyl magnesium bromide, and then use the manufactured Grignard reagent to synthesize the alcohol, triphenylmethanol, by reacting with benzophenone and protonation by H3O+.
I then added a solution of diphenylmethanone in anhydrous ether (AKA benzophenone) to the Grignard reagent and observed a brilliant array of color change. Julianne Tieu Organic Chemistry I ( – ) May 30, Lab Report for Experiment #2: Solubility Part A: 1.
Summarize your results in table form (Cover Sheet). 2. Explain the results for all the tests done. Samples of benzophenone, malonic acid, and biphenyl were each tested with water, methyl alcohol, and hexane. There were four test tubes for 91%(53). Benzophenone is the organic compound with the formula (C 6 H 5) 2 CO, generally abbreviated Ph 2 CO.
It is a white solid that is soluble in organic solvents. Benzophenone is a widely used building block in organic chemistry, being the parent diarylketone.