CHEM 2125L: ORGANIC CHEMISTRY II LAB Spring 2018

Transcription

1 CHEM 2125L: ORGANIC CHEMISTRY II LAB Spring 2018 Instructor: Jose L. Ontiveros, Jr. Office Mailbox: STC 318 Office Hours: Wednesdays and Thursdays 1:00 pm 1:50 pm, STC 301 or by appointment Lab Section 04: Thursday 2:00 pm 5:50 pm, STC 308 COURSE INFORMATION Text/Manual and other required material: Lab Manual: Introduction to Organic Laboratory Techniques: A Small-Scale Approach, Fourth Edition. Pavia/Lampman/Kriz/Engel, 2016, ISBN-13: Supplies should be purchased before the first lab meeting: ANSI certified safety glasses, two combination locks per group, and a bound notebook. Course Description: Traditional and combinatory synthetic routes used in organic synthesis are compared. The concept of reaction kinetics will be explored using UV-Vis spectroscopy as it applies to organic reactions by calculating its rate constant in Microsoft Excel. Also, an in-depth look into the syntheses of various organic compounds obtained from noteworthy reactions will be studied this semester. A mastery of the purification (solubility, crystallization, extraction) and characterization (IR, 1 H-NMR, and 13 C-NMR) techniques learned in CHEM 2123 are essential for success in this course. Prerequisites (min. C grade): CHEM 1312, 102 and Corequisites: CHEM 201 and Student Learning Outcomes/Course Objectives: By the end of the semester I intend for my students to realize some objectives. 1. Learn basic synthetic organic chemistry techniques, such as how to set up reactions, how to monitor the progress of a reaction, how to calculate the number of starting materials needed, how to calculate percent yields, and how to properly clean glassware after each experiment. 2. Learn how to characterize organic compounds using techniques and instrumentation such as melting point, boiling point, retention factor, 1 H-NMR, 13 C-NMR, IR, and UV/Vis spectroscopy. 3. Learn the safety requirements and methods needed to work in an organic chemistry laboratory. 4. Learn how to handle, utilize and safely dispose of chemicals. 5. Learn how to document laboratory experiments, maintain a scientific notebook and write a formal laboratory report. 6. Know the importance of organic chemistry and its relationship to other disciplines (biochemistry and medicinal chemistry) and how these concepts connect to our daily lives. GRADING The student s laboratory grade will be based on 8 of the best experimental write-ups (out of 9), a formal report, and a spectroscopy packet containing IR, 1 H-NMR, and 13 C-NMR. Notebook and Post-lab Write-up: 80% Formal Laboratory Report: 10% Spectroscopy problems: 10% 100% CHEM 2125 Spring 2018 Page 1

2 Students are required to submit all lab write-ups via . Late notebooks and post-labs will not be accepted unless proper documentation can be supplied for the unexcused absence. If a laboratory experiment is missed, it will count as the dropped laboratory grade. If the student misses more than one laboratory experiment, a zero will be given for that assignment. Dishonest scholarship will earn an automatic zero (0) and initiate prosecution to the fullest extent. Grading is based on a standard percentage scale: 59-below = F; = D; = C; = B; = A. Incomplete grades may be given only if the student has a current average 70% and is precluded from completion of the course by a documented illness or family crisis. See the following website for more details about course withdrawal deadlines: TAMUC Academic Calendar. Lab Cleanliness: You will be expected to maintain a clean and orderly lab. At the end of every experiment, your bench space and hood space must be cleaned. Any equipment utilized during the experiment must be cleaned before you leave for the day. You should also check the sinks and floors for any debris or abandoned glassware. If the lab space and equipment that you utilized during the experiment is left dirty and unorganized, you will be penalized 20% on your lab report associated with that experiment. COMMUNICATION AND SUPPORT Communication: If the instructor needs to contact an individual student, it will be via the student s e- mail account on file. It is the responsibility of the student to notify the instructor of his/her absence before class begins. is the best, easiest and fastest way to communicate with me. s sent on Friday will be answered on Monday the following week. LABORATORY NOTEBOOK AND FINAL REPORT GRADING RUBRIC Laboratory Notebooks: You must write down what you observe and take measurements during the time of the experiment. Compose the laboratory notebook in sufficient detail to allow someone else to repeat the experiment exactly. You will not be allowed to bring in your lab textbook. The observations section of the report must be the original notes taken during the experiment (take detailed, legible notes during the experiment). You can also submit a typed version of your observations if you wish, but you MUST submit your original notes taken during the experiment. Each laboratory report will consist of the following sections: 1. Laboratory Notebook 40 points (Notebooks are due at the beginning of the laboratory) o Title 1 point 1. Example: Exp. 1 Title of experiment o Physical Constants/Reagent Data Table 10 points 1. Make a table(s) to clearly list the chemical and physical properties of all the solvents and chemicals you will use. a) The properties include but are not limited to: amount in grams and/or ml (depends on physical state), molecular weight, density, moles, equivalence (eq.), melting point (m.p.), boiling point (b.p.), actual yield, theoretical yield, percent yield, color, phase, flammability, toxicity and safety notes. o Stoichiometry/Theory 5 points 1. Chemical Reaction 2 points (goes before reagent table) 2. How much of each reactant should be used 1 point (listed in the reagent table) 3. What s the theoretical yield by calculation 2 points (list value in table) CHEM 2125 Spring 2018 Page 2

3 o Safety 5 points 1. Read the special instruction part carefully so that you are not injured. 2. How to deal with the dangerous chemicals and operations should be listed clearly. o Procedure and Observations 15 points 1. Itemized and step by step (Don t copy the textbook directly) 2. You are encouraged to explain the key steps after the particular procedures 3. Observations ( T chart Procedure on the left, Observations on the right or viceversa) a. List the phenomenon you have observed such as bubbles formed, the color of the mixture changed from colorless to rose; two layers were formed from one phase, green crystals formed o Student Signature and Experiment Completion Date 1 point 1. Standard procedure and authenticates your work o Instructor s Initials 3 points 1. Notebook was completed as prescribed by instructor 2. Proof that you completed the lab and not counted absent 3. Hood/bench area is clean, and all glassware has been put away 2. Post-Laboratory Write-up 60 points (due by the beginning of the next laboratory period) o Observations 15 point 1. Once the experiment has been performed, transcribe your observations into complete sentences. Be sure to include details about the instruments, equipment, glassware, reagents amounts, techniques, time durations and physical appearances that you observed during the reaction. o Results 15 points 1. Show calculations for determining the limiting reagent, theoretical yield, percent yield 2. Report melting point range. 3. Attach your labeled experimental NMR/IR and literature handouts. o Discussion 15 points 1. Discuss why your results were what they were using the concepts presented in the lab manual and lecture textbook. a) Discuss the reaction theory and factors that affect the reaction b) Explain the mechanism c) Compare your experimental proton NMR data to the literature handout. (i.e., This means what chemical shifts are present or absent in your experimental NMR.) 2. Report all sources of error that justify your percent yield, experimental NMR impurities and melting point range. a) Identify the problem b) Come up with a solution to fix the problem. c) What effect does this solution have on your percent yield, experimental NMR impurities and melting point range? o Questions 15 points Answer the assigned problems according to the syllabus in complete sentences.* 3. Final Report 60 points (due by the beginning of the next laboratory period) o Abstract 5 point CHEM 2125 Spring 2018 Page 3

4 3. Give a summary, typically 3-5 sentences to a paragraph, about the experiment. The abstract MUST contain this information in as succinct a manner as possible: major experiment and techniques, major data, major conclusions, and a reaction scheme. The abstract should not contain every finding or conclusion, and should not have a detailed procedure, but you must address all these areas. It should be written in passive, past tense, and not first person. The abstract is the last thing a scientist writes. (Burling) o Introduction 10 points 1. The introduction is included in the formal report for a few reasons. First, it gives the reader background on the scientific issues being discussed. What are some of the key terms and definitions used? How have other scientists approached the problem in the past and what have they concluded? Second, it gives the reader a perspective of why the research and findings are important to the scientific community. The introduction, therefore, is often highly cited with previous works. ***This section is the hardest section for an inexperienced scientist to write because it requires some more substantial background in the field. Therefore, in this course, you will be given guidance for each paper in the type of sources to use.*** (Burling) (i.e., ACS Journal of Chemical Education) o Results 15 points 1. What s the physical property of your product? (melting point, color, phase) 2. How much product did you get in this part? (You should show your original data and the calculation process; three significant digits after the decimal are required.) 3. Calculate your actual yield o Discussion 15 points 1. Discuss why your results were what they were using the concepts presented in the lab manual and lecture textbook. a. Discuss the reaction theory and factors that affect the reaction b. Explain the mechanism in words c. Compare your experimental data ( 1 H-NMR, 13 C-NMR, IR) to the literature. (i.e., This means what chemical shifts/bands are present or absent in your experimental NMR.) 2. Report all sources of error that justify your percent yield, experimental data, melting point range and any impurities. a. Identify the problem b. Come up with a solution to fix the problem. c. What effect does this solution have on your percent yield, experimental data, melting point range and impurities? 3. Answer the assigned problems according to the syllabus in complete sentences.* o Conclusion 5 points 1. Write a few sentences that provide a summary of what you said in the introduction, results, and discussion and conclude with a valid scientific interpretation of what your data means. o Experimental Procedure 5 points 1. This is the place where organic chemists give a detailed procedure of each reaction or experiment performed. First, you will write a paragraph outlining the general materials and equipment. 2. The next paragraph will outline the next experiment with a heading in bold. If it is a synthetic experiment, the heading will be the name of the compound made. CHEM 2125 Spring 2018 Page 4

5 If you used another paper as a reference for your procedure, cite the paper here. Following the name, a detailed procedure is given. It is written in the past, passive. It includes actual gram or volume amounts used as well as molar amounts of reagents. The procedure should be detailed enough that someone else could successfully repeat the experiment exactly as you did. After the procedure, the amount of product obtained, product observations, and % yield are given. This is followed by a summary of all the characteristic data (m.p., TLC R f and solvent system, IR data and sample technique, 13C, and 1 H NMR data, and any other characterization data) (Burling). o References 5 points 3. Be sure that you have correctly cited all of your sources in ACS format. *Any responses given as answers to textbook questions should not come from any homework help website (Chegg, Course Hero, etc.). Simply for the fact that some responses have been seen to come from the Instructor s Manual. Use caution and best judgment practices. If you are in doubt, see me. This class requires you to use and develop your critical thinking skills. COURSE AND UNIVERSITY POLICIES Class Attendance Policy: All students are expected to attend classes on a regular basis and attendance will be recorded. The Department of Chemistry adheres to the attendance policy set by the University as stated in the most current Undergraduate Catalog. Being late by more than 5 minutes is equivalent to missing a laboratory. You must be on time to take a quiz or an exam. Excessive absence is defined as missing more than 10% of the laboratory sessions without excusable reasons. Excessive absence will be reported to the Dean of the College and the Dean of Students. Also, according to the TAMU- Commerce Procedure A13.02., good class attendance will be necessary to pass the course. Student Conduct Policy: All students enrolled at the University shall follow the tenets of common decency and acceptable behavior conducive to a positive learning environment (see Student s Guidebook, Policies, and Procedures, Conduct). Any student engaging in disruptive behavior will be dismissed from class on the first offense. A second offense may constitute dismissal from the course. Nondiscrimination Statement: Texas A&M University-Commerce will comply in the classroom, and in online courses, with all federal and state laws prohibiting discrimination and related retaliation on the basis of race, color, religion, sex, national origin, disability, age, genetic information or veteran status. Further, an environment free from discrimination on the basis of sexual orientation, gender identity expression will be maintained. Academic Integrity and Dishonesty Policy: Academic cheating, plagiarism, and other forms of academic misconduct may result in removal of the student from class with a failing grade or may in extreme cases result in suspension or expulsion from the University as described in the Code of Student Conduct section of the Student1s Guidebook A&M-Commerce Procedure R0.10. ADA Statement: The Americans with Disabilities Act (ADA) is a federal anti-discrimination statute that provides comprehensive civil rights protection for persons with disabilities. Among other things, this legislation requires that all students with disabilities be guaranteed a learning environment that provides for reasonable accommodation of their disabilities. If you have a disability requiring an accommodation, please contact: CHEM 2125 Spring 2018 Page 5

6 Office of Student Disability Resources and Services Texas A&M University-Commerce Gee Library- Room 162 Phone (903) or (903) Fax (903) TENTATIVE LABORATORY SCHEDULE OF EXPERIMENTS Week Chapter/Topic Dates Experiments & Assigned Problems 1 1st Week of Classes 1/18 The lab will not meet this week. Monday - Martin Luther King Jr. Day 2 2nd Week of Classes 1/25 Syllabus, safety lecture, exam, notebooks, checkout 3 Experiment 17 & 18 An Introduction to Molecular Modeling and Computational Chemistry 2/1 Training on how to use computational chemistry software Spartan (second-floor computer lab). Read experiment 17 and 18 before class. Read the essays in the chapters before class. Conduct exercises 17A-17D and 18 A-D. Notebooks are not required. Bring a pen to write responses on a handout given by the instructor. 4 Combinatory Chemistry 2/8 5 Oxidation of Alcohol 2/ Experiment 34 Aqueous-Based Organozinc Reactions Experiment 42 Relative Reactivities of Several Aromatic Compounds Experiment 41 1,4-diphenyl-1,3- butadiene (Wittig reaction) 2/22 3/1 3/8 Read and follow the pre-lab directions given in the handout. Attach your spectra (IR and 1 H- NMR) and questions to your lab write-up. A handout will be given out that describes this experiment. Microsoft Excel will be used to calculate the rate constant. Bring your laptop to class. Read experiment 34. Answer questions 1-4 on page 289, interpret your spectra (IR, 1 H-NMR, and 13 C-NMR), and attach it to your lab writeup. Read experiment 42. Answer questions 1-3 on page 335, interpret your spectrum ( 1 H-NMR) and attach it to your lab write-up. Read experiment 41B. Answer questions 1, 3, and 4 on page 330, report your melting point, interpret your spectrum ( 1 H-NMR) and attach it to your lab write-up. The next 3 labs will test your synthetic chemistry skills as the product from one experiment will be utilized for the next experiment. So hopefully you have material at the end of each lab that will serve as your starting material for the subsequent lab. Week Chapter/Topic Dates Experiments & Assigned Problems 9 SPRING BREAK 3/12-3/16 CHEM 2125 Spring 2018 Page 6

7 Experiment 32A Benzoin by Thiamine Catalysis Experiment 32B Benzil. Experiment 32C Benzilic Acid Experiment 50AB Polyesters and Polyamides Experiment 16 Ethanol from Sucrose Experiment 37 The Aldol Condensation: Benzalacetophenones (Chalcones) 3/22 3/29 4/5 4/12 4/19 4/26 Read experiment 32A: KEEP your product at the end of this experiment because you will use it next week. Answer questions 1 and 4 on page , melting point, interpret your spectrum ( 1 H-NMR) and attach it to your final report. Read experiment 32B. Use your product from last week as this weeks starting material. KEEP your product at the end of this experiment because you will use it next week. Obtain a melting point, interpret your spectrum ( 1 H- NMR) and attach it to your final report. Read experiment 32C. Use your product from last week as the starting material. Obtain yields from each step and the overall yield for the three-step reaction for your report. Answer questions 1-3 on page , melting point, interpret your spectrum ( 1 H-NMR) and attach it to your final report. Read the essay on pages : Polymers and Plastics. Conduct experiments 47A and 47B. Answer questions 1-7 on page 400 and attach it to your lab write-up. Set up experiment 16 for next week. Read the essay on page 116: Ethanol and Fermentation Chemistry. Complete experiment 16 which was started last week. Answer questions 1-6 on page 123 and attach to your lab write-up. Read experiment 37. Answer questions 1, 2, and 4 on page , melting point, interpret your spectra ( 1 H-NMR and 13 C-NMR) and attach it to your lab write-up with a balance equation of the reaction. Check-out. Spectroscopy packets are due. Note: The instructor reserves the right to make any changes to the syllabus CHEM 2125 Spring 2018 Page 7