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CHEM234 Fitch SP2023 S YNTHESIS OF F ERROCENE D IGITAL L ABORATORY R EPORT PREPARED BY : G AVYN W OO D ATE : 2/10/2024 L AB R OOM : M ILLIS 310 TA: SUPERSTAR P URPOSE The purpose of this experiment was to perform the synthesis of acetylferrocene through a Friedel-crafts acylation using ALCl 3 . R EACTION S CHEME ( MUST BE CREATED USING CHEMDRAW FOR FULL CREDIT ) N ARRATIVE /P ROCEDURE AND O BSERVATIONS — M UST BE IN THIRD PERSON , PAST TENSE , AND PARAGRAPH FORM . T HE NARRATIVE SHOULD INCLUDE THE MEASURED QUANTITIES ( MASS / VOLUME ) OF EACH REAGENT , ALONG WITH QUANTITIES AND PHYSICAL DATA FOR EACH PRODUCT . To begin the laboratory, all glassware used was flame dried to make sure that there was no water inside. They were also rinsed with acetone to clean. After that, fresh drierite was packed into a drying tube. After this, 150mg of AlCl3 was added to a 10-round-bottomed flask. The same apparatus from the previous experiment was used. This included a claisen head, a drying tube, a round bottom flask, a stir bar, and caps for the claisen head. After that, 2.5ml of CH 2 Cl 2 was added to the round bottom flask as well as 80 microliters of acetyl chloride. It was observed a reaction taking place and a color change from clear to dark brown. Next, a 150mg portion of ferrocene was weighed out and put into a v-vial along with 2.5 ml of CH 2 Cl 2 . The ferrocene was dissolved completely and this solution was then added to the round bottom flask. It was then stirred for 20 minutes. It was observed that the contents of the round bottom flask turned a dark red color. Once the 20 minutes were up, the contents of the reaction apparatus were transferred to a plastic centrifuge tube containing 5 ml of ice water. It was observed here that the solution separated into two layers, one being more clear than the other. The tube was then cooled in an ice bath and the pH was adjusted until the aqueous layer was just basic. using 0.5ml of 25% NaOH. Following this, the mixture was extracted 3 different times with 3 ml portions of CH 2 Cl 2 . After this, the combined extracts were dried using anhydrous Na 2 SO 4 contained in a filter pipette. This was drained into a pre weighted 25 ml round bottom flask. The solution was then taken to the rotovap and weighed to get the produced weight. It was observed that the product retrieved was 0.2241g. 0.1ml was saved from the solution to run a TLC on. A TLC plate, capillary tubes, a pencil, a rectangular piece of filter paper, and a TLC jar were obtained. The TLC plate was set up correctly with pencil marks 1 cm from the bottom and 1 cm from the top. Next, a solution of diluted ferrocene was made from 0.5ml of CH 2 Cl 2 and ferrocene. After this, a droplet of liquid

CHEM234 Fitch SP2023 extract was put on marks labeled A and B on the TLC plate. After this, drops of diluted ferrocene were put on marks labeled B and C. Once done, the TLC plate was put into the TLC jar and ran. In column A, one dot was observed at 5.1cm up from the starting TLC line. In column B it was observed two dots at points 1.7 and 5.2cm. Finally, in column C it was observed one dot at 1.6cm. D ATA T ABLE ( S )— M UST BE IN TABLE FORM TO RECEIVE CREDIT Mass of ferrocene Mass of crude product 0.1491g 0.2241g Solvent front distance Solvent spot distance from each line A 7.5cm 5.1cm B 7.5cm 1.7cm and 5.2cm C 7.5cm 1.6cm S AMPLE C ALCULATIONS — U SE BASIC DIMENSIONAL ANALYSIS TO DETERMINE THE FOLLOWING ( ASSUME FULL CONVERSION TO THE STATED PRODUCT ): Calculate the theoretical yield of monoacetylferrocene. Assume that the mass of and that all product formed is monoacetylferrocene Mass of ferrocene = 186.04g Mass of monoacetylferrocene = 228.07g Mass of product = 0.2241g 228.07g / 186.04g * 0.2241 = 0.275g(theoretical yield) Calculate the theoretical yield of bis -diacetylferrocene. Assume that the mass of and that all product formed is bis -diacetylferrocene Mass of ferrocene 186.04g Mass of bis-diacetylferrocene = 270.1g Mass of product = 0.2241g 270.1g / 186.04g * 0.2241g = 0.3254g (theoretical yield) Calculate the retention factor of ferrocene on the silica plate. = 0.68 𝑅 𝑓 = 5.1𝑐𝑚 7.5𝑐𝑚

CHEM234 Fitch SP2023 R ESULTS — M UST BE IN TABLE FORM TO RECEIVE CREDIT Retention Factor A Ferrocene 0.68Rf B Mixture 0.23Rf and 0.69Rf C Diluted ferrocene 0.21Rf C ONCLUSION Q UESTIONS — M UST BE ANSWERED IN COMPLETE SENTENCES ; M AY USE C HEM D RAW OR HAND DRAWN PHOTOS 1. Describe the purpose of using each of the following reagents from this experiment’s synthesis (a) ferrocene, (b) aluminum trichloride, (c) acetyl chloride and (d) methylene chloride. A.) Ferrocene was used to synthesize acetyl ferrocene. It is required as a reactant. B.) Acts as a Lewis acid and generates electrophile. C.) This is a reagent needed to form acetyl ferrocene. D.) It is used as a solvent for the reaction. 2. Use the TLC results to qualitatively describe how the reaction progressed. Connect your observed bands to the likely synthetic products. Based on the results of the TLC, you can see that there were two Rf values for the co-spot and only one for each of the others. You can see how pure and polar each substance was too based on their Rf values. Furthermore, you can see the separation at the co-spot between the product mixture and the pure product. 3. Two of the reaction conditions shown below ( I ➝ III ) have been utilized in either Experiment 1 or 2 of CHEM 234. The other reaction is simply an acid-catalyzed dehydration. i. benzene + CH 3 CH 2 COCl + AlCl 3 ➝ compound ( W ) ii. compound ( W ) + PhCH 2 MgBr + (CH 3 CH 2 ) 2 O ➝ compound ( X ) + HCl aq. ➝ compound ( Y ) iii. compound ( Y ) + H 2 SO 4 + heat ➝ compounds ( Z n ) a. Write down line-angle structures for compounds W , X, and Y W: X:

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CHEM234 Fitch SP2023 Y: b. Reaction ( III ) potentially produces a mixture of isomers (therefore Z n ). Draw line-angle structures for the isomers formed in this dehydration. c. Indicate what kind of isomers are the compounds ( Z n ). There may be more than one relationship possible. The compounds Zn are geometric isomers and E/Z isomers. d. Reactions ( I ) and ( II ) may fail completely if water is present. Reaction ( III ) may proceed even if water is present. Write a concise paragraph explaining these potential outcomes. The reactions may fail if water is present in between reactions because , in reaction 1, if water is present, it will react so that propionyl chloride is no longer available as an electrophile for the reaction. This would then make the reaction fail. Furthemore, in reaction 2 , if water is present it will react with the grignard reagent to form ketone. This makes the grignard reagent no longer available as a nucleophile and therefore the reaction will fail.

CHEM234 Fitch SP2023 4. Aniline is more nucleophilic than toluene. However, if we subjected both compounds to the reaction conditions utilized in experiment 3, only toluene would yield a Friedel-Crafts product. Explain this difference in reactivity. You may incorporate structures or a mechanism in your proposed answer. This change in reactivity is because the nucleophilic order is Aniline and then toluene. This is because of lone pairs on the Nitrogen of aniline because of this, the electron density increases in the ring which increases the nucleophilicity. Aniline doesn’t give Friedel-Crafts product because AlCl 3 is a lewis acid and the ring is not nucleophilic.