ORGANIC CHEMISTRY 301

EXAMINATION THREE-Nov. 25, 1996

I. (Four points each)

a. Complete the following drawing to represent the mirror image of the drawn compound.

b. Draw a stereochemical drawing for 2R,3R-2,3-dichloropentane.

c. Which of the following compounds will have the same [a] as compound I?

d. Completely name the following compound:

II. (Three points each) Consider the following reaction:

a. What is the total number of products expected from the reaction?

b. How many will be chiral?

c. How many can be separated from each other?

III. (Three points each) Complete the following reactions for the mechanisms stated. Include stereochemistry, where applicable.

SN₁

a. R-2-bromopentane + OH^- ®

E₂

b. R-2-bromopentane + OH^- ®

SN₂

c. R-2-bromopentane + CN^- ®

d. 1-bromopentane + Li ® ? + D₂O ® ?

E₁

e. R-2-bromopentane + OH^- ®

f. R-2-bromopentane + OH^-/H₂O ®

III. (Four points each)

a. Non-polar solvents favor much type of reactions of alkyl halides and nucleophiles? Why?

b. Which of the following are related? How. R , S , d, a, [a].

c. Which type of reaction, unimolecular or bimolecular, is stereospecific? Explain why.

d. How does alpha-elimination differ from the E₂ and E₁ processes, in general?

e. Which reaction type SN₁, SN₂, E₁, E₂ can produce the largest number of products? Explain.

f. Why should there be an inverse preference of the SN₂ and SN₁ processes for the type of alkyl halide, primary, secondary, etc.?