GENERAL INFORMATION
ON THE
INORGANIC PREPARATIONS COURSE

Note: This course is required by the American Chemical Society for a certified degree in chemistry.
  1. Required Materials
  2. Goals of the Course
  3. Text
  4. Lectures
  5. Attendace
  6. Plan of the Course
  7. Nature of the Synthesis
  8. Difficulties to be Expected
  9. Grading
  10. Useful References

REQUIRED MATERIALS:

  • Laboratory notebook as described below.
  • Safety goggles and lab coat.

    • I. Goals of the Course

    The purpose of the Inorganic Preparations course is to give the student experience in solving problems dealing with the synthesis and characterization of inorganic and organometallic compounds. The goal is to give the student a "real life" experience with the techniques of doing modern chemistry. The syntheses have been selected for at least one of three purposes:
    1. To introduce a new technique. In real synthetic work, many compounds have properties such as thermal instability, extreme ease of hydrolysis (moisture in the air or in undry solvents), extreme ease of oxidation (atmospheric oxygen), or inconveniently high or low volatility which make them difficult to handle on the open lab bench. The synthesis, manipulation, and characterization of such compounds thus requires exclusions of air and moisture, and equipment like inert atmosphere glove bags, Schlenk reaction vessels and vacuum lines have been developed for this purpose. Other compounds require special conditions for their formation, such as reactions in a high temperature tube furnace, or for their purification, like high vacuum sublimation.
    2. To introduce a new, different, or unusual type of inorganic or organometallic compound. The hundred-odd elements in addition to carbon form compounds exhibiting a fantastic variety of structures, reactions, reactivities, forms of bonding and stereochemistry.
    3. To prepare a starting material for a research laboratory. From time to time students doing research need compounds that are not commercially available. Thus, the purpose of some syntheses is to provide substances for ongoing and future research projects. Students have an opportunity to gain experience in an actual research laboratory, and may even be included on a publication.

    II. Text

    There is no assigned text. A list of important and useful books is attached at the end of this handout. Many of the syntheses are found either in reference texts or in the research journals.

    III. Lectures

    We will meet once each week with the entire class Thursday 10-10:50. The instructor, teaching assistant, or an invited speaker will discuss safety, fundamentals of selected techniques, methods of purification, and characterization. The instructor or a TA will always be in the lab with you to answer any questions you may have pertaining to your work. Do not hesitate to ask questions.

    IV. Attendance

    Technically, University regulations require three hours of class work per credit hour of laboratory. In this course, the number of hours is determined by the amount of time it takes each student to complete the assigned experiments. You are asked to sign in when you start your lab work and sign out when you leave. The hours in which the laboratory is open for your use will be given to you by the teaching assistant. The important point is that the work be completed. The best and most productive students often require the least time in the laboratory. If you miss two weeks of work before you have completed the assignments, you fail the course.

    V. Plan of the Course

    1. General Syntheses. You will be expected to manage your time effectively to accomplish six (seven for the case of 512 students) synthetic experiments during the semester. The particular experiments that you carry out will be assigned by the instructors as the semester progresses. One of your preparations will be a "Special Project" (see later).
      The order of the preparations must be carefully scheduled to allow the best use of all the equipments available. The instructors in charge of the course will schedule the experiments. See the teaching assistant before you finish your current preparation so that you will be able to plan for the next preparation.
      It is expected that the student will have researched the important aspects of a synthesis (such as the necessity for preliminary steps like solvent drying, distillation or purification of starting materials, etc.) and the nature of the compounds used before work begins and that the student has formulated a reasonable plan for using the laboratory time.
    2. Special Project. One of the special features of this course is that new experiments are tried each semester. The experiments that work well are added to the standard list of experiments for following semesters, and less valuable experiments are phased out.
      Some students may be attempting syntheses that have never been carried out in this laboratory before. Common sources for new experiments are Inorganic Syntheses, J. Chem. Ed., the Handbook of Preparative Inorganic Chemistry, G. Brauer (QD151 B7333) and other sources in the Science Library. The instructor, teaching assistants, or other research groups in the department may also make some suggestions. The experiment should be the preparation of an interesting inorganic compound or material, or involve a useful technique.
      The object is not to attempt an extremely difficult experiment. It is more important to show that you can plan and accomplish an experiment within the time and equipment constraints of this course. You will present a poster on your special project on May 8th. All plans should be checked with the instructor before anything is done.

    VI. Nature of the Syntheses

    Often the assigned synthesis will have to be modified in various ways. Probably the most common change will be scaling down the size of the reaction. This is done for several reasons, such as the lack of any current research need for the product and, recently, the cost of chemicals and equipment. Before starting a synthesis, inform the instructor of the amounts of starting materials you intend to use and the amount of product you expect to obtain. Occasionally a literature synthesis will call for a special piece of apparatus that may not be available in the lab or stockroom. This will necessitate improvising equipment or partially redesigning the experiment. When this occurs, consult the instructor. It should be noted that this is a common problem in real research labs.
    Occasionally it may be necessary to repeat a synthesis, since some reactions or techniques may be tricky and unfamiliar. This happens in real laboratories.

    VII. Difficulties to be Expected

    The main difficulty you will experience will be collecting and assembling apparatus and chemicals. Sometimes the lab will be out of a chemical or a piece of equipment will not be available. Equipment scrounging will cost time. This can be minimized by a well thought-out approach to your work. These difficulties are common to just about any lab, teaching or research. Please do not attempt to do things without first consulting the TA. If a piece of equipment is misplaced then the TA may know where it is or how to "improvise" a replacement. Please consult the TA when a difficulty arises.

    VIII. Grading

    There will be no written examinations or final exam but there will be a poster session at the end of the semester. You will present your special project in the poster session. Grades will be assigned on the basis of the following:
    1. The product. Quality as well as quantity are important. Quality will be judged by purity (melting point, spectral characterization, etc.) and appearance (color, size of crystals, etc.). Quantity will be judged by the percent yield. This will be compared to the value claimed in the literature - which is usually higher than is possible in this laboratory. All products must be turned in, in a container suitable for long term storage in an ordinary laboratory. This means that products which hydrolyze or oxidize in air must be torch-sealed in a nitrogen-filled all-glass ampoule or storage tube (made from a test tube). The samples will be looked at when first turned in and periodically thenafter.
    2. The notebook. In real life the purpose of a laboratory notebook is to provide an accurate permanent record of exactly what was done and of what happened as a result. Often years pass between the performance of an experiment and the realization of the complete significance of the result. Obviously one's memory cannot be trusted to retain all the details of the work and the existence of a well-kept record under such circumstances is imperative. The notebook is also essential if a patent is to be applied for.
      Your lab notebook should be a clear record of how you performed your synthesis and of what happened. All difficulties you experienced, all modifications you made, and all suggestions for improvement you might make should be detailed. The notebook should be kept as work progresses, and not written up later.
      Specific expectations for the notebook are:
      • The notebook should be of the type that has duplicate pages with carbon paper between. This type of notebook is slightly more expensive but allows for the removal of the duplicate copy to serve as the report for the experiment, while you still have the notebook in your possession. Photocopies are also acceptable.
      • The notebook should be clearly labeled on the outside.
      • The first few pages should be reserved for an index.
      • Each entry should include the date at which it is entered into the notebook. Also include the time so that significant observations can be related to how long a reaction has been proceeding.
      • The description of each preparation should include, before any part of that experiment is performed, the following items:
        • A brief description of the purpose of the preparation including theory and the structure of the molecule being synthesized.
        • Any references to the literature which have been utilized.
        • A brief description of the best synthetic route for preparing the compound, including special techniques, precautions, expected yield, physical charac- teristics and method of characterization.
        • A list of the chemicals and items of equipment required, with quantities scaled to a suitable level.
        • These entries should be approved and initialed by the teaching assistant before the work is to begin.
      • A detailed description of the actual laboratory work is to follow. This should include diagrams of the apparatus utilized and all observations, including spectra. A well-written description will allow a reader to actually visualize what took place.
      • The final comments and conclusions should include:
        • An identification of the purity of the product, as determined by physical or spectral properties (such as color, solubilities, NMR and IR frequencies, etc.).
        • The percent yield of the product obtained.
        • A summary of the weaknesses of the preparation.
        • Any suggestions for improvement in the procedure.
      • Additional information on the laboratory notebook can be found in the texts by Angelici and Jolly.
    3. Laboratory Performance.
      • Be prepared when entering the lab. The TA should be informed before the lab of what you will be doing and if there are any special needs. You should know the material in the pre-lab notebook write-up. Be prepared to answer questions about what you are making, what you are doing, etc.
      • Schedule your time appropriately. Be prepared to finish on time. Take advantage of waiting times in a preparation to clean glassware, improve your notebook comments, prepare for the next step, study the next preparation, etc.
      • Keep your working area clean and uncluttered both during the preparation and at the end of the day. Return all equipment to the proper storage locations.
      • Always be conscious of safety.
      • Above all, think about what you are doing. Have in mind some explanation of what you are doing in each step and how it fits into the entire preparation. The instructors will be asking you to explain what you are doing.
    4. Physical Data We expect you to explain all the spectra, such as NMR, IR, UV-Vis, etc., and physical data, such as magnetic suscepibilities,etc. Interpretation the major peaks and why. you have to explain the meaning of the peak and more. Any unexplained spectra will be treated as none.
    5. Interpretation of results and answering questions We expect you to explain all the phenomenon during and after the reaction, the meaning of physical data, answer any questions might appear in the web.

    IX. Useful References (Science Library)

    1. Common sources of syntheses.
      1. * Inorganic Syntheses (QD151 A1 I5) A multivolume collection of checked syntheses.
      2. * Handbook of Preparative Inorganic Chemistry, G. Brauer, ed. (QD151 B733) A two volume collection of strictly inorganic (no C- not even a CH3 group) syntheses.
      3. The Synthesis and Characterization of Inorganic Compounds, W.L. Jolly ,(QD156 J65) A useful collection of lab techniques and syntheses. Instructor also has a copy.
      4. Synthesis and Technique in Inorganic Chemistry, R.J. Angelici (QD155 A53)
    2. Sources of information on inorganic compounds, reactions, and chemistry.
      1. Basic Inorganic Chemistry, F.A. Cotton and G. Wilkinson (QD151.2 C69) An excellent introductory text.
      2. Advanced Inorganic Chemistry, F.A. Cotton and G. Wilkinson (QD151.2 C68 1972) The best advanced one volume text (the big brother of b-1 above). The 1966 and 1962 editions are also good.
      3. Modern Inorganic Chemistry, J.J. Lagowski (QD151.2 L34) A good introductory text.
      4. Inorganic Chemistry, R.B. Heslop and P.C. Robinson (QD151 H47 1967) Similar to b-3, but older.
      5. Inorganic Chemistry, J.E. Huheey (QD151.2 H84) An excellent introductory text - especially good on transition metal compounds and bio-inorganic chemistry.
      6. Coordination Chemistry, F. Basolo and R. Johnson (541.396 B316) An elementary text on transition metal complexes.
      7. Elementary Coordination Chemistry, M.M. Jones (541-396 J78) An introductory text.
      8. *Comprehensive Inorganic Chemistry, J.C. Bailar, et al., ed. (QD151.2 C64) A modern five volume treatise. When all else fails, try this.
      9. Advances in Inorganic Chemistry and Radiochemistry, (QD151 A45) A multivolume collection of reviews on specific topics.
      10. Progress in Inorganic Chemistry, (546 P964) Like b-9.
    3. Sources of information on lab methods and techniques.
      1. a-3 and a-4, above. Very useful.
      2. The Manipulation of Air Sensitive Compounds, D.F. Shriver (QD61 557) The best source of information on inert atmosphere and high vacuum methods and Schlenk techniques.
      3. Laboratory Technique in Organic Chemistry, K.B. Wiberg (547.072 W632) In spite of the title, a useful book on lab operations, especially solvent purifica- tion.
      4. Microscale Inorganic Chemistry, Z. Szafran, R.M. Pike, M.M. Singh.
      5. Purification of Laboratory Chemicals, D.D. Perrin, W.L.F. Armarego.
    4. Sources of information on the characterization of compounds by spectroscopic methods.
      1. Physical Methods for Chemists, R. S. Drago.
      2. Structural Methods in Inorganic Chemistry, E.A.V. Ebsworth, D.W.H. Rankin, S. Cradock.
      3. Spectrometric Identification of Organic Compounds, R.M. Silverstein, G.C. Bassler and T.C. Marrill (QD272 S6 555 1974) An excellent practical introduction to nmr, ir, ms, etc. The earlier editions (547.364 S587) are also very good.
      4. * Instrumental Methods of Analysis, Willard, Merritt & Dean (QD79 I5 W54 1974) Standard introductory text.
      5. Infrared Spectra of Inorganic and Coordination Compounds, K. Nakamoto (1st ed. 535.842 N163; 2nd ed. QC457 N3 1970) Excellent, but more advanced.
      6. *An Index of Vibrational Spectra of Inorganic and Organometallic Compounds, Greenwood, Ross & Stranglian (QC453 G742) A bibliography of references to papers on the ir spectra of a huge number of inorganic compounds.
    5. Some advice on finding information.
      1. If a book is checked out, you can probably borrow the instructor's copy.
      2. If you really can't get to first base after an hour's honest effort, see the instructor.
    (* indicates books located in reference room)