The Two-Step Organic Synthesis of 4-Bromoacetanilide and How Green Chemistry Principles Apply Green chemistry principles in the analysis of two-bromoacetanilide. step of organic synthesis of 4-bromoacanilide. This experience was relevant because of the importance of green chemistry principles in environmental and health safety. It was found that it was still possible to obtain an appropriate percentage yield of 68% through the modified reaction sequence (Table 1). Both class and individual performances showed that it is possible to perform the alternative, greener reaction and still achieve the desired results. Spectroscopy data were analyzed to confirm the identity of acetanilide and 4-bromoacetanilide. The alternative reaction was shown to be the more optimal reaction than the standard reaction, due to the green chemistry principles it followed. These principles are important for human health and environmental protection and the modified reaction used in the laboratory was a step in the right direction to make reactions chemically greener. Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”?Get original essayIntroductionThe purpose of this experiment was to use the principles of green chemistry to analyze the two-step organic synthesis of 4-bromoacetanilide . The standard reaction sequence discussed in this experiment produces harmful byproducts and wastes.3 The cost of properly disposing of hazardous substances is high.2 Green chemistry principles are used in order to create a better reaction sequence and safer. An acyl transfer reaction is used in this experiment to form acetanilide from aniline. This acyl transfer reaction is used as a protecting group, which allows the acetanilide to undergo mono-substitution instead of multiple substitutions.1 Since acetanilide is more acidic, it will facilitate the reaction between HOCl and NaBr since these Reactions are usually assisted by an acid.4 This implements the green chemistry principles of prevention and use of less hazardous chemicals. The balanced equations for the two-step synthesis performed in the laboratory are shown below. The first reaction forms the compound acetanilide while the second forms 4-bromoacetanilide. Methods Acetylation reactionFirst, 2 mL (22 mmol) of aniline and 4 mL (69 mmol) of glacial acetic acid were mixed together in a dry and clean 25 mL round bottom flask. A stirring bar was incorporated into the mixture and the air condenser and adapter were attached to the flask. The mixture was brought to a boil at around 370-430°C with stirring. During this time, the movement of the condensation ring was carefully observed. When the condensation ring rose halfway up to two-thirds of the way up the condenser, the heat was lowered by 5 to 10°C. At this time, the reaction was refluxed for 90 minutes and the height of the condensation ring was again carefully monitored. The reaction was removed from the heat after 90 minutes and cooled before being poured into 30 ml of cold ice water in a 100 ml container. cup. This mixture was cooled and stirred in an ice water bath until crystallization was complete. The crystals were then collected with a Büchner filter and washed twice with 10 ml of ice-cold water. Once the acetanilide crystals were dry, they were massagedto obtain 1.808 g (61%) of a white solid: melting point 108-111 °C with decomposition [lit.5 mp 113-114 °C]; IR 3291, 3067, 3027, 1662, 1499, 1262 cm-1; 1H NMR (500 MHz, CDC13) δ 2.16 (3H, s), 7.11 (1H, t), 7.31 (2H, m), 7.5 (2H, d), 7.65 (1H , s); 13C NMR (125.7 MHz, CDC13) δ 24.6, 120.1, 124.5, 129.1, 138, 168.8. Bromination reactionFirst, 1.0 g (7.4 mmol) of acetanilide was mixed with 1.8 g (17.5 mmol) of NaBr in a 125 ml Erlenmeyer flask. with 6 ml of 95% ethanol, 5 ml of acetic acid and a stirring bar. This reaction was stirred in an ice water bath for 5 minutes. Once complete, 10.7 mL (7.8 mmol) of NaOCl was added to the mixture and the reaction was removed from the ice water bath after stirring for an additional 5 min. After allowing the mixture to sit for 15 minutes, it was cooled again over an ice water bath. A solution was prepared of 1.0 g of sodium thiosulfate added to 1.0 g of sodium hydroxide in 10 ml of distilled water. This preparation was incorporated into the reaction mixture then mixed for 15 minutes. The crude product formed was then recovered by vacuum filtration and washed with 10 ml of distilled water. Once dry, 50% ethanol was used to recrystallize the crude product. The recrystallized 4-bromoacetanilide product was collected and massed to obtain 1.076 g (68%) of a white solid: melting point 167-168 °C with decomposition [lit. 5 melting point 167-169 °C]; IR 3300, 3064, 2928, 1667, 1536, 1258 cm-1; 1H NMR (500 MHz, DMSO) δ 2.04 (3H, s), 7.47 (2H, d, J = 2.5 Hz), 7.57 (2H, d, J = 2.5 Hz), 10.06 (1H, s); 13C NMR (125.7 MHz, DMSO) δ 24.4 (2.04), 114.9, 121.3 (7.57), 131.9 (7.47), 139.1, 168.9. Table 1. The table below shows the yields and yield percentages of the class and individual data of the Acetanilide and 4-bromoacetanilide products. It can be seen that the average yield of the acetanilide class was 1.84 grams while the individual yield was 1.808 grams. Lower individual performance is the reason why the overall individual performance percentage is lower than the class value. The standard deviation of the acetanilide class performance was 0.23. This means that there was virtually no deviation from the average, meaning that individual performance was actually below average. The standard deviations of the class percent yields for acetanilide and 4-bromoacetanilide are 7.9 and 12.2, respectively. This means that more groups deviated from the true mean, showing that the individual percentage yields for both substances were comparatively similar to the mean. Table 2. The table below shows the IR spectrum frequencies of acetanilide. with their missions. The frequency at 3291 cm-1 was assigned to an NH bond, which is consistent with the NH bond that was part of the amide at the frequency of 1662 cm-1. This amide group also confirms the identity of the acetanilide products. Table 3. The table below shows the peaks of the 13C NMR spectrum for acetanilide in ppm along with the number of attached hydrogen atoms and peak assignments. The structure on the left of the table shows where each peak is assigned on the structure. The number of attached hydrogen atoms is consistent with the structure assignments for each different peak. This confirms the identity of acetanilide instead of 4-bromoacetanilide due to the presence of a hydrogen atom attached to carbon 6, whereas in 4-bromoacetanilide there was no hydrogen atom attached. Table 4. The table below shows the 1H NMR spectrum of acetanilide as well as the structure which corresponds to the missions. The peak values in ppm are indicated as well as the number of hydrogen atomsattached to each different peak. The peak values are consistent with the values given in the starting information. The amount of hydrogen atoms that correspond to each different peak is also consistent with its corresponding assignment in the acetanilide structure. The identity of acetanilide is further confirmed due to the hydrogen atom attached to the carbon at the E position, whereas in 4-bromoacetanilide there was no hydrogen atom there . 4-Bromoacetanilide Spectroscopy TablesTable 5. The table below shows the frequencies of acetanilide. IR spectrum of 4-bromoacetanilide as well as their assignments. The frequency at 3300 cm-1 was assigned to an NH bond, which is consistent with the NH bond that was part of the amide at the frequency of 1667 cm-1. This amide group also confirms the identity of the product as 4-bromoacetanilide.Table6. The table below shows the peaks of the 13C NMR spectrum for 4-bromoacetanilide in ppm along with the number of attached hydrogen atoms and peak assignment. The structure on the left of the table shows where each peak is assigned on the structure. The number of attached hydrogen atoms is consistent with the structure assignments for each different peak. This confirms the identity of 4-bromoacetanilide instead of acetanilide because there is 0 hydrogen atom attached to carbon 6, whereas in acetanilide there was 1 hydrogen atom attached. Table 7. The table below shows the 1H NMR spectrum for 4-bromoacetanilide with the structure that matches the missions. Peak values in ppm are shown along with the number of hydrogen atoms attached to each different peak. The peak values are consistent with the values given in the starting information. The amount of hydrogen atoms that correspond to each different peak is also consistent with its corresponding assignment in the structure of 4-bromoacetanilide. The identity of 4-bromoacetanilide is further confirmed as there is no longer a hydrogen atom attached to the carbon that is now attached to the bromine, whereas in acetanilide there was a hydrogen atom at this place. The COZY pairing information is also displayed in the Mult. column.Table 8. The table below presents HSQC data for 4-bromoacetanilide. 13C NMR peaks are shown with their corresponding 1H NMR peaks where applicable. Only three 1H NMR peaks are shown since the final peak was attached to a nitrogen atom instead of a carbon. This confirms the identity of the 4-bromoacetanilide product. DiscussionThe two reactions performed in this experiment present the principles of green chemistry. The main guiding principles presented are prevention, use of less hazardous chemical syntheses, safer solvents and auxiliaries, efficiency, reduction of derivatives and inherently safer chemistry for accident prevention.5 Prevention is an important principle to use in this discussion because of the change in experiences. from the most dangerous standard procedure to the safer procedure that was actually performed. With this in mind, the use of less hazardous chemical syntheses and safer solvents and auxiliaries are two key factors in the green chemistry analysis of this experiment. These factors show the negative qualities of the standard procedure and illustrate the positive qualities of the modified procedure. The effectiveness is visible in the standard procedure and will be explained in more detail later. The green chemistry principle of reduced derivatives is evidenced in the use of protecting groups in both reactions and for this reason it is included in this discussion. The final guiding principle of the discussion is the use ofinherently safer chemicals for accident prevention. This principle can be used to examine to what extent the modified reaction is chemically safer than the standard procedure. These are the broad guiding principles that can be used to analyze both reaction sequences and their ability to be considered green. The first principle of discussion is prevention. In the standard procedure for the formation of 4-bromoacetanilide, HBr was produced as a byproduct with the possibility that unreacted Br2 would be present after the reaction was complete. This is a problem because HBr is a strong, toxic acid and Br2 is corrosive and toxic.5 These are not substances that are good to keep after the reaction is complete. The modified reaction sequence, however, solves this problem. In the modified reaction, safer reagents are used in order to produce only water and NaCl as byproducts. Water can be easily released into the environment and NaCl is a much safer alternative to Br2 or HBr. Therefore, the modified reaction sequence is chemically greener than the standard procedure with respect to the prevention principle. As part of prevention, there are the principles of using less dangerous chemical syntheses and safer solvents and auxiliaries. The standard reaction uses materials like acetic anhydride and bromine, which are reactive and toxic to humans and the environment. The standard reaction then generates more toxic and corrosive materials such as HBr and Br2. This shows the complete disregard of the standard reaction for green chemistry. The materials used in the modified reaction sequence are also not entirely safe and harmless. Bleach is used as the source of HOCl, instead of acetic anhydride. Being able to avoid acetic anhydride is beneficial, but bleach is also toxic to humans and the environment and can be deadly if mixed with the wrong substances. Modified reactions using NaBr as a reagent, on the other hand, are positive due to its low toxicity. Again, the modified reaction also generates safer byproducts that are not as harmful as those produced in the standard reaction. Even with the use of bleach, the modified reaction is still considered to be chemically greener than the standard reaction sequence. Two principles of green chemistry that both reaction sequences demonstrate are efficiency and reduction of derivatives. Aside from the production of toxic materials in the standard reaction sequence, both reactions proceed very well on their own.5 It is possible to achieve high yield from these reactions and obtain a pure compound having a melting point almost identical to that of literature. value.3 Efficiency is an important element of green chemistry because less energy and resources must be used to achieve the desired product. Both reactions also display the principle of reduced derivatives. A reagent used in both reaction sequences is aniline. Since aniline strongly activates the benzene ring to which it is attached, the ring can undergo many substitution reactions. This can be problematic since multiple substitutions can produce uncontrollable side products, which can lead to various complications. To counteract this, the amino group can be acetylated, which would cause it to undergo only mono-substitution. The acyl group acts as a protecting group in both of these reaction sequences. Although the protective groups help to avoid generating other by-products and waste, they require a step..

Essay / The Two-Step Organic Synthesis of 4-Bromoacetanilide and How Green Chemistry Principles Apply Green chemistry principles in the analysis of two-bromoacetanilide. step of organic synthesis of 4-bromoacanilide. This experience was relevant because of the importance of green chemistry principles in environmental and health safety. It was found that it was still possible to obtain an appropriate percentage yield of 68% through the modified reaction sequence (Table 1). Both class and individual performances showed that it is possible to perform the alternative, greener reaction and still achieve the desired results. Spectroscopy data were analyzed to confirm the identity of acetanilide and 4-bromoacetanilide. The alternative reaction was shown to be the more optimal reaction than the standard reaction, due to the green chemistry principles it followed. These principles are important for human health and environmental protection and the modified reaction used in the laboratory was a step in the right direction to make reactions chemically greener. Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”?Get original essayIntroductionThe purpose of this experiment was to use the principles of green chemistry to analyze the two-step organic synthesis of 4-bromoacetanilide . The standard reaction sequence discussed in this experiment produces harmful byproducts and wastes.3 The cost of properly disposing of hazardous substances is high.2 Green chemistry principles are used in order to create a better reaction sequence and safer. An acyl transfer reaction is used in this experiment to form acetanilide from aniline. This acyl transfer reaction is used as a protecting group, which allows the acetanilide to undergo mono-substitution instead of multiple substitutions.1 Since acetanilide is more acidic, it will facilitate the reaction between HOCl and NaBr since these Reactions are usually assisted by an acid.4 This implements the green chemistry principles of prevention and use of less hazardous chemicals. The balanced equations for the two-step synthesis performed in the laboratory are shown below. The first reaction forms the compound acetanilide while the second forms 4-bromoacetanilide. Methods Acetylation reactionFirst, 2 mL (22 mmol) of aniline and 4 mL (69 mmol) of glacial acetic acid were mixed together in a dry and clean 25 mL round bottom flask. A stirring bar was incorporated into the mixture and the air condenser and adapter were attached to the flask. The mixture was brought to a boil at around 370-430°C with stirring. During this time, the movement of the condensation ring was carefully observed. When the condensation ring rose halfway up to two-thirds of the way up the condenser, the heat was lowered by 5 to 10°C. At this time, the reaction was refluxed for 90 minutes and the height of the condensation ring was again carefully monitored. The reaction was removed from the heat after 90 minutes and cooled before being poured into 30 ml of cold ice water in a 100 ml container. cup. This mixture was cooled and stirred in an ice water bath until crystallization was complete. The crystals were then collected with a Büchner filter and washed twice with 10 ml of ice-cold water. Once the acetanilide crystals were dry, they were massagedto obtain 1.808 g (61%) of a white solid: melting point 108-111 °C with decomposition [lit.5 mp 113-114 °C]; IR 3291, 3067, 3027, 1662, 1499, 1262 cm-1; 1H NMR (500 MHz, CDC13) δ 2.16 (3H, s), 7.11 (1H, t), 7.31 (2H, m), 7.5 (2H, d), 7.65 (1H , s); 13C NMR (125.7 MHz, CDC13) δ 24.6, 120.1, 124.5, 129.1, 138, 168.8. Bromination reactionFirst, 1.0 g (7.4 mmol) of acetanilide was mixed with 1.8 g (17.5 mmol) of NaBr in a 125 ml Erlenmeyer flask. with 6 ml of 95% ethanol, 5 ml of acetic acid and a stirring bar. This reaction was stirred in an ice water bath for 5 minutes. Once complete, 10.7 mL (7.8 mmol) of NaOCl was added to the mixture and the reaction was removed from the ice water bath after stirring for an additional 5 min. After allowing the mixture to sit for 15 minutes, it was cooled again over an ice water bath. A solution was prepared of 1.0 g of sodium thiosulfate added to 1.0 g of sodium hydroxide in 10 ml of distilled water. This preparation was incorporated into the reaction mixture then mixed for 15 minutes. The crude product formed was then recovered by vacuum filtration and washed with 10 ml of distilled water. Once dry, 50% ethanol was used to recrystallize the crude product. The recrystallized 4-bromoacetanilide product was collected and massed to obtain 1.076 g (68%) of a white solid: melting point 167-168 °C with decomposition [lit. 5 melting point 167-169 °C]; IR 3300, 3064, 2928, 1667, 1536, 1258 cm-1; 1H NMR (500 MHz, DMSO) δ 2.04 (3H, s), 7.47 (2H, d, J = 2.5 Hz), 7.57 (2H, d, J = 2.5 Hz), 10.06 (1H, s); 13C NMR (125.7 MHz, DMSO) δ 24.4 (2.04), 114.9, 121.3 (7.57), 131.9 (7.47), 139.1, 168.9. Table 1. The table below shows the yields and yield percentages of the class and individual data of the Acetanilide and 4-bromoacetanilide products. It can be seen that the average yield of the acetanilide class was 1.84 grams while the individual yield was 1.808 grams. Lower individual performance is the reason why the overall individual performance percentage is lower than the class value. The standard deviation of the acetanilide class performance was 0.23. This means that there was virtually no deviation from the average, meaning that individual performance was actually below average. The standard deviations of the class percent yields for acetanilide and 4-bromoacetanilide are 7.9 and 12.2, respectively. This means that more groups deviated from the true mean, showing that the individual percentage yields for both substances were comparatively similar to the mean. Table 2. The table below shows the IR spectrum frequencies of acetanilide. with their missions. The frequency at 3291 cm-1 was assigned to an NH bond, which is consistent with the NH bond that was part of the amide at the frequency of 1662 cm-1. This amide group also confirms the identity of the acetanilide products. Table 3. The table below shows the peaks of the 13C NMR spectrum for acetanilide in ppm along with the number of attached hydrogen atoms and peak assignments. The structure on the left of the table shows where each peak is assigned on the structure. The number of attached hydrogen atoms is consistent with the structure assignments for each different peak. This confirms the identity of acetanilide instead of 4-bromoacetanilide due to the presence of a hydrogen atom attached to carbon 6, whereas in 4-bromoacetanilide there was no hydrogen atom attached. Table 4. The table below shows the 1H NMR spectrum of acetanilide as well as the structure which corresponds to the missions. The peak values in ppm are indicated as well as the number of hydrogen atomsattached to each different peak. The peak values are consistent with the values given in the starting information. The amount of hydrogen atoms that correspond to each different peak is also consistent with its corresponding assignment in the acetanilide structure. The identity of acetanilide is further confirmed due to the hydrogen atom attached to the carbon at the E position, whereas in 4-bromoacetanilide there was no hydrogen atom there . 4-Bromoacetanilide Spectroscopy TablesTable 5. The table below shows the frequencies of acetanilide. IR spectrum of 4-bromoacetanilide as well as their assignments. The frequency at 3300 cm-1 was assigned to an NH bond, which is consistent with the NH bond that was part of the amide at the frequency of 1667 cm-1. This amide group also confirms the identity of the product as 4-bromoacetanilide.Table6. The table below shows the peaks of the 13C NMR spectrum for 4-bromoacetanilide in ppm along with the number of attached hydrogen atoms and peak assignment. The structure on the left of the table shows where each peak is assigned on the structure. The number of attached hydrogen atoms is consistent with the structure assignments for each different peak. This confirms the identity of 4-bromoacetanilide instead of acetanilide because there is 0 hydrogen atom attached to carbon 6, whereas in acetanilide there was 1 hydrogen atom attached. Table 7. The table below shows the 1H NMR spectrum for 4-bromoacetanilide with the structure that matches the missions. Peak values in ppm are shown along with the number of hydrogen atoms attached to each different peak. The peak values are consistent with the values given in the starting information. The amount of hydrogen atoms that correspond to each different peak is also consistent with its corresponding assignment in the structure of 4-bromoacetanilide. The identity of 4-bromoacetanilide is further confirmed as there is no longer a hydrogen atom attached to the carbon that is now attached to the bromine, whereas in acetanilide there was a hydrogen atom at this place. The COZY pairing information is also displayed in the Mult. column.Table 8. The table below presents HSQC data for 4-bromoacetanilide. 13C NMR peaks are shown with their corresponding 1H NMR peaks where applicable. Only three 1H NMR peaks are shown since the final peak was attached to a nitrogen atom instead of a carbon. This confirms the identity of the 4-bromoacetanilide product. DiscussionThe two reactions performed in this experiment present the principles of green chemistry. The main guiding principles presented are prevention, use of less hazardous chemical syntheses, safer solvents and auxiliaries, efficiency, reduction of derivatives and inherently safer chemistry for accident prevention.5 Prevention is an important principle to use in this discussion because of the change in experiences. from the most dangerous standard procedure to the safer procedure that was actually performed. With this in mind, the use of less hazardous chemical syntheses and safer solvents and auxiliaries are two key factors in the green chemistry analysis of this experiment. These factors show the negative qualities of the standard procedure and illustrate the positive qualities of the modified procedure. The effectiveness is visible in the standard procedure and will be explained in more detail later. The green chemistry principle of reduced derivatives is evidenced in the use of protecting groups in both reactions and for this reason it is included in this discussion. The final guiding principle of the discussion is the use ofinherently safer chemicals for accident prevention. This principle can be used to examine to what extent the modified reaction is chemically safer than the standard procedure. These are the broad guiding principles that can be used to analyze both reaction sequences and their ability to be considered green. The first principle of discussion is prevention. In the standard procedure for the formation of 4-bromoacetanilide, HBr was produced as a byproduct with the possibility that unreacted Br2 would be present after the reaction was complete. This is a problem because HBr is a strong, toxic acid and Br2 is corrosive and toxic.5 These are not substances that are good to keep after the reaction is complete. The modified reaction sequence, however, solves this problem. In the modified reaction, safer reagents are used in order to produce only water and NaCl as byproducts. Water can be easily released into the environment and NaCl is a much safer alternative to Br2 or HBr. Therefore, the modified reaction sequence is chemically greener than the standard procedure with respect to the prevention principle. As part of prevention, there are the principles of using less dangerous chemical syntheses and safer solvents and auxiliaries. The standard reaction uses materials like acetic anhydride and bromine, which are reactive and toxic to humans and the environment. The standard reaction then generates more toxic and corrosive materials such as HBr and Br2. This shows the complete disregard of the standard reaction for green chemistry. The materials used in the modified reaction sequence are also not entirely safe and harmless. Bleach is used as the source of HOCl, instead of acetic anhydride. Being able to avoid acetic anhydride is beneficial, but bleach is also toxic to humans and the environment and can be deadly if mixed with the wrong substances. Modified reactions using NaBr as a reagent, on the other hand, are positive due to its low toxicity. Again, the modified reaction also generates safer byproducts that are not as harmful as those produced in the standard reaction. Even with the use of bleach, the modified reaction is still considered to be chemically greener than the standard reaction sequence. Two principles of green chemistry that both reaction sequences demonstrate are efficiency and reduction of derivatives. Aside from the production of toxic materials in the standard reaction sequence, both reactions proceed very well on their own.5 It is possible to achieve high yield from these reactions and obtain a pure compound having a melting point almost identical to that of literature. value.3 Efficiency is an important element of green chemistry because less energy and resources must be used to achieve the desired product. Both reactions also display the principle of reduced derivatives. A reagent used in both reaction sequences is aniline. Since aniline strongly activates the benzene ring to which it is attached, the ring can undergo many substitution reactions. This can be problematic since multiple substitutions can produce uncontrollable side products, which can lead to various complications. To counteract this, the amino group can be acetylated, which would cause it to undergo only mono-substitution. The acyl group acts as a protecting group in both of these reaction sequences. Although the protective groups help to avoid generating other by-products and waste, they require a step..

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