Abstract: A mixture of Fluorene (1) and Fluorenone (2) was separated by column chromatography.
Chemical Equation: Fluorene (1) Fluorenone (2) Mp 114C mp 83C MW 166.22 MW 180.21
Introduction:
Column chromatography was invented by Tswett in 1906 so that his study of the chemistry of chlorophyll could be facilitated. Tswett made significant advances in the method and demonstrated its applicability to the separation of many different kinds of mixtures. Column chromatography rapidly found application in all areas of chemistry and is used extensively today because it is a simple but powerful tool for the separation of pure compounds from a complex mixture. It cannot affect the same degree of separation as TLC, but its advantage over TLC is the fact that large amounts of mixtures (over 5 g) can easily be treated by this method. There are, however, a number of important similarities between TLC and column chromatography which, when the two methods are used in complementary fashion, allow preparative separations to be accomplished easily and quickly. The same comments that were made concerning adsorbents and solvents for TLC apply also to column chromatography. In particular, by using TLC initially to determine a solvent system for separation of a mixture, one can quickly find the solvent system that will effect separation of the same mixture on a column of the same adsorbent. (In other words, if a particular solvent system effects separation on, say, alumina with TLC, a very similar solvent system will effect separation of a column, provided that alumina of the same type is used as adsorbent.
Results and Discussion: Of the initial 100mg of Fluorene (1), 8.2mg was recovered. Of the initial 100mg of Fluorenone (2), 52.8mg was recovered. These calculated into a percent recover of:
8.2mg/100mg = 8.2% for the Fluorene (1) and 52.8mg/100mg = 52.8% for the Fluorenone (2). These numbers were
References: “Techniques in Organic Chemistry”, J. R. Mohrig, C. N. Hammond, P. F. Schatz, W. H. Freeman and Co., NY, 2006, p 116. “Chromatographic Separation of Fluorene (1) and Fluorenone (2)”, E. Kho, UHH, HI, 2009. “http://www.chemistry.adelaide.edu.au/cdrom/PracCDROM/2nd_Year/ChemIIE/Semester1/ChemIIE_Expt01.pdf”