A. (5x5=25) Complete each of the following reactions with the major organic product.

E2 only

alkyl shift

S_N2 attack at the least hindered carbon by CN^-, which is a very good nucleophile and relatively weak base.

B. (3x5=15) For each reaction below, write, in the box provided, the reagents needed to change the starting material on the left into the product on the right.

Without the acid the addition of methanol won’t proceed.

Without a metal catalyst, the addition of H₂ won’t proceed.

C. (2x5=10) The reagents and products of two reactions are shown below. Draw the structure of the starting material that will lead to the product(s) shown.

1,

D. (10) Draw reactions needed to prepare 2-methyl-1-propanol, B, from 2-methyl-2-propanol, A. There is no single reaction that will do the job. The most efficient strategy is to work backwards from B.

E. (10) Draw a mechanism for the following reaction. Use the curved arrow convention. Clearly show the intermediates and the correct number of steps.

F. In the addition of HBr to 1,3-butadiene the intermediate carbocation, B, is formed. Two products, C and D, are formed from B.

(a) (8) On the energy diagram below locate A, B, C and D by writing those letters in the the appropriate boxes. (There are too many boxes and some should be empty.)

(I can’t reproduce the diagram here.)

Only the four boxes that correspond to minima on the diagram are filled. From left to right the boxes should be, in order, A, B, C (for the upper one) and D (for the lower one).

(b) (4) Which is the product of kinetic control? ___C____

(c) (4) Which is the product of thermodynamic control? ___D____

G. (5) Draw one more of the five major resonance forms possible for the anion below.

(b) (4) How many signals would appear in the ¹³C NMR spectrum of the resonance stabilized anion above.

____one_______

Because of resonance, all C’s are equivalent.

H. (5) Draw the product of the following reaction, showing its stereochemistry.

anti addition of Br₂