Grignard Reaction Lab Report

3382 Words14 Pages
The formation of new carbon-carbon bonds is of central importance in organic chemistry and a prerequisite for all life on earth. Through the assembly of carbon atoms into chains, complex molecules, e.g. molecules of life, can be created. The importance of the synthesis of carbon-carbon bonds is reflected by the fact that Nobel Prizes in Chemistry have been given to this area many times: the Grignard reaction (1912), the Diels-Alder reaction (1950), the Wittig reaction (1979), and olefin metathesis to Y. Chauvin, R. H. Grubbs, and R. R. Schrock (2005) and Richard F. Heck , Ei-ichi Negishi, Akira Suzuki (2010) for the development of methods for palladium-catalyzed formation of carbon-carbon
…show more content…
The mixture is ‘spotted’ at the bottom of the TLC plate and allowed to dry. The plate is placed in a closed vessel containing solvent (the mobile phase) so that the liquid level is below the spot. TLC has advantages over paper chromatography in that its results are more reproducible, and that separations are very efficient because of the much smaller particle size of the stationary phase. The solvent ascends the plate by capillary action, the liquid filling the spaces between the solid particles. This technique is usually done in a closed vessel to ensure that the atmosphere is saturated with solvent vapour and that evaporation from the plate is minimised before the run is complete. The plate is removed when the solvent front approaches the top of the plate and the position of the solvent front recorded before it is dried (this allows the Rf value to be calculated). TLC has applications in industry in determining the progress of a reaction by studying the components present; and in separating reaction…show more content…
Many compounds decompose at the temperatures required for efficient GC separation while HPLC separation can be achieved readily. However, GC is particularly useful in detecting residual solvents in formulations and is also invaluable in looking for degradation products. Amines and acids are not separated well by GC because they tend to be too polar.

Spectroscopy is a technique that is used for the detailed analysis of the compound and its structure prediction. There are various techniques:
Ultraviolet–visible spectroscopy refers to absorption spectroscopy or reflectance spectroscopy in the ultraviolet-visible spectral region. This means it uses light in the visible and adjacent (near-UV and near-infrared (NIR)) ranges. In this region of 200nm-700nm the molecules undergo electronic transitions. This is based upon the beer lambert law which states that whenever a monochromatic light is passed through a absorbing sample then the decrease in the light intensity is exponentially proportional to the concentration and the thickness of the sample: I0 = intensity of incident light
I = intensity of transmitted light c = concentration of the medium l = thickness of the

More about Grignard Reaction Lab Report

Open Document