麻省理工学院：《有机化学基本实验操作技巧》教学资源（讲义）Looks can be Deceiving

WARNING NOTICE: The experiments described im these materials are pote ardous and require a highlevel ofafcty training special faclities and equip mgat, and supervision by appropriate individuals. You bear the sole responsibility, liability, and riskfor the implementation of such safety procedures and measures. MrT shall haveno responsibility, liability, or risk for the content or implementation of any of the material presented. Legal Notices 4. Purification by Flash Column Chromatography 4.1. Competent Chemist Rating: "Looks Can Be Deceiving Techniques Checklist Analyzing mixtures by tlC Assembling a silica gel column Applying crude mixtures to a silica gel column Separating simple mixtures with a silica gel column Pre-lab Discussion and Required reading: Theory of column chromatography: Zubrick Ch 27 TLC -polarity/solvent systems: Zubrick Ch. 28, LLP Ch 9.3.1 Setting up a silica gel column: Zubrick Ch. 29, LLP Ch. 11.6 Applying crude mixtures to the column Running a flash column quipment Flash Chromatography Column Air flow apparatus(stopper, T-valve, screw clamp, tubing) 100-mL Round-bottomed flask Test tubes-18x150 mm Test tube rack TlC plates and spotters Large plastic funnels Digital Lab Techniques Manual ·3.TLC: The basics 10. Column Chromatography Goal: Purify a contaminated compound using silica gel flash column chromatography

4. Purification by Flash Column Chromatography 4.1. Competent Chemist Rating: “Looks Can Be Deceiving” Techniques Checklist: • Analyzing mixtures by TLC ❑ • Assembling a silica gel column ❑ • Applying crude mixtures to a silica gel column ❑ • Separating simple mixtures with a silica gel column ❑ Pre-lab Discussion and Required Reading: • Theory of column chromatography : Zubrick Ch. 27 • TLC - polarity/solvent systems: Zubrick Ch. 28, LLP Ch. 9.3.1 • Setting up a silica gel column: Zubrick Ch. 29, LLP Ch. 11.6 • Applying crude mixtures to the column • Running a flash column Equipment: • Flash Chromatography Column • Air flow apparatus (stopper, T-valve, screw clamp, tubing) • 100-mL Round-bottomed flask • Test tubes - 18x150 mm • Test tube rack • TLC plates and spotters • UV lamp • Large plastic funnels Digital Lab Techniques Manual: • 3. TLC: The Basics • 10. Column Chromatography Goal: • Purify a contaminated compound using silica gel flash column chromatography. 28 WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. WARNING NOTICE: The experiments described in these materials are potentially hazardous and require a high level ofsafety training, special facilities and equipment, and supervision by appropriate individuals. You bear the sole responsibility, liability, and risk for the implementation of such safety procedures and measures. MIT shall have no responsibility, liability, or risk for the content or implementation of any of the material presented. Legal Notices

Experiment Outline: You will receive 2 mL of an ether/pentane solution containing 1.00 g of benzy lactone contaminated with a small amount of guaiazulene Make a TLC sample, and analyze this mixture by TLC, using 10% ethyl acetate/hexanes as the solvent system-see TLC Guide Record the r values. Prepare the column in the hood, using 10% ether/pentane and 50 g(about 5")of silica gel-see Flash Column Chromatography guide Elute the column with 10 mL of pentane Apply your sample to the column, being careful not to disturb the top layer of sand. Rinse the sample flask three times with l mL pentane each, and use the rinses to wash the sides of the column Run the column-See Flash Column Chromatography Guide Monitor the fractions by tlC- See TLC Guide Concentrate the set of fractions containing pure benzylacetone Weigh the purified compound and prepare a gc sample Obtain a tLC and a gas chromatogram of the purified compound Benzalacetone To obtain your CC Rating"in Purification by Flash Column Chromatography you must collect at least 0.95 g of benzylacetone. This sample must be at least 95%o pure as demonstrated using gas chromatography. Your sample must also be submitted to the TA for possible weight and purity verification

Experiment Outline: • You will receive 2 mL of an ether/pentane solution containing 1.00 g of benzylacetone contaminated with a small amount of guaiazulene. • Make a TLC sample, and analyze this mixture by TLC, using 10% ethyl acetate/hexanes as the solvent system - see TLC Guide. • Record the Rf values. • Prepare the column in the hood, using 10% ether/pentane and 50 g (about 5’’) of silica gel - see Flash Column Chromatography Guide. • Elute the column with 10 mL of pentane. • Apply your sample to the column, being careful not to disturb the top layer of sand. Rinse the sample flask three times with 1 mL pentane each, and use the rinses to wash the sides of the column. • Run the column - See Flash Column Chromatography Guide. • Monitor the fractions by TLC - See TLC Guide. • Concentrate the set of fractions containing pure benzylacetone. • Weigh the purified compound and prepare a GC sample. • Obtain a TLC and a gas chromatogram of the purified compound. CH3 H3C O CH3 CH3 H3C Benzylacetone Guaiazulene Results: • To obtain your "CC Rating" in Purification by Flash Column Chromatography, you must collect at least 0.95 g of benzylacetone. This sample must be at least 95% pure as demonstrated using gas chromatography. Your sample must also be submitted to the TA for possible weight and purity verification. 29