1. (16 pts) Give acceptable names for the following compounds, being sure to address alkene geometry and R/S configuration where appropriate.

2. (14 pts) For each of the following four molecules, list the properties from the list on the right which best describe it. Each item on the list can be used as often as necessary, or not at all. DON'T GUESS!!

a. contains no sp2 carbons b. forms another functional group when oxidized or reduced c. forms a salt with NH3 d. very easily oxidized, even by atmospheric O2 e. is not reduced by LiAlH4 f.incompatible with Grignard reagents g. lowest vapor pressure of the four h. reacts with NaBH4 to form an alcohol i. made in one step from a 2o alcohol j. most basic of the four molecules k. can be formed from oxidation of a 1o alcohol

3. (30 pts) Complete the following reactions (provide either the starting molecule, the reagent(s), or product(s). If more than one product is produced, draw them all. If one product predominates, circle it.

4. (16 pts) Provide a synthesis of any TWO (2) of the following four molecules from the indicated starting materials. You may use any inorganic reagents you like, but all carbon atoms must come from the starting material provided. Please fill in the letter of your choices in the spaces provided below and on the following page. DO NOT use illegal starting materials; doing so will cost half the points right off the top.

5. (16 pts) Please explain the following observations.

a. The compound illustrated in the box has the following measurement: [a]25 = +43o. When a tiny amount of anhydrous HCl or a catalytic amount of base is added, the +43 number slowly declines, finally settling at 0o.

Regardless of whether base or acid is used, the intermediate is planar, so that when it tautomerizes to the keto form (acid) or reprotonates (base), the random nature of these processes means that chirality is lost, and a racemic mixture is obtained.

b. What is the effect of an electron-withdrawing substituent on the basicity of aniline? Using resonance, illustrate this effect using p-nitroaniline. Answers without at least two resonance structures will not be graded.

Nitro, being one of the great electron-withdrawing groups, pulls the electron density from the NH₂ lone pair, making it less available for attack by an acid, reducing its basicity.  This is particularly clear in the right-most structure, showing delocalization all the way up into the NO₂ oxygen atom.

6. (8 pts) Rank the molecules in the box from most acidic to least acidic, by placing the letters corresponding to each molecule in the appropriate rank supplied below.

 Most acidic = 1. __C__ 2. __G__ 3. __I__ 4. __D__ 5. __F__ 6. __B__ 7. __H__ 8. __E__ 9. __A__ =Least acidic

A common method for the a-bromination of simple ketones and aldehydes involves simply dissolving the substrate in acetic acid and treating it with bromine. Provide the mechanism of this straightforward reaction, as illustrated in the box. Hint: the acid solvent is involved, and catalyzes a certain transformation.

The acid serves to catalyze the enolization of the ketone, which, as mentioned in class, is the nucleophilic species when carbonyls react with electrophiles.  The enol, by losing its proton, attacks the Br₂ with its two π electrons, and re-forming the carbonyl in the process.