Meeting 3 Problem Set - 30BL

1.Using PC Spartan 2002 at the Science Learning Center (4 Floor Young Hall) do the following:

a. Draw camphor if you have not done it yet (Make sure that all hydrogen atooms are still attached!). Minimize the structures by clicking the minimize icon, , then save.

b. Go to the view mode by clicking the view icon, . Once in the view mode, click the Model menu and select Tube.

c. Select Calculations from the Setup menu.

The following window should appear. Select the options shown.



Verify the Charge is Neutral and Multiplicity is Singlet. Click OK.

• Select Submit from Setup menu.

  
  

  Under the Setup menu, select Surfaces. A window should appear. In this window click Add.

  

  A second window should appear. In this window, select the following

  

  Then click OK to exit dialog. Close the previous window.

  Select Submit from Setup menu. When the calculation is completed you will be notified.

  Under the Display menu, select Surfaces.

  

  A window should appear. In this window check the yellow box.

  

  Next, select the molecule by clicking on it. In the bottom right corner of the window, change the selection from Solid to Transparent.

d) Do the same (steps a-c) for 2-norbornanone.

2. Referring to the below reaction,

(endo/exo huh?)

answer the following questions:

a. Which isomer is expected to be the major product for this reaction? why? (Include the LUMO diagrams generated in question 1 to answer this question. Make sure to show the proper orientation!)

b. What would change if LiAlD₄ and D₂O were used in this reaction?

c. What is the driving force for the reaction?

answer the following questions:

a. Draw the products formed in this reaction

b. which product is the major and which is the minor? Explain using the LUMO generated above (Include the LUMO diagrams generated in question 1 to answer this question. Make sure to show the proper orientation!)

c. What would change if NaBH(CN)₃ were used in this reaction instead of NaBH₄?

4. One critical point in the reduction of camphor was the proper choice of solvent.

a. Which solvent is used for the reaction? Rationalize the choice.

b. Which problem does this solvent pose for the reaction? How are the problems minimized?

5. How many grams of sodium borohydride are needed to reduce 0.100 g of camphor? Show pertinent chemical equation and calculations.

6. The crude product is redissolved in diethylether. Why is step performed?

7. A student forgets to remove the drying agent before boiling off the solvent. What would he observe?

8. The student observes a melting point of 175-179 ^oC for his final product. Which conclusion can he draw from this observation?

9. Why is it considered poor lab techniques to leave bottles and containers open?