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CHEM1. Classify each of the following reactions as either an oxidation or reduction (8 points).
b. OCH3OCH3 Na, NH3
2. NaOH, ∆
2. Explain the following observation (10 points)? O
3. Which of the following undergoes decarboxylation (loss of CO2) the easiest? Explain your
reasoning (10 points).
HO2C O CO2H
A B C
4. Phenyl selenium halide (Ph-SeX) is an electrophilic reagent used to oxidize cyclic ketones to
α,β – unsaturated ketones. Using the following scheme, provide a mechanism for this reaction (Hint: think Cope elimination) (12 points).
O O1. LDA, -78 °C
2. Ph-SeCl 3. H2O2
5. Enolate formation is greatly influenced by both the choice of base and the temperature of the
reaction. Given the following reaction conditions, predict the products that would be formed and
provide an explanation for why each one is formed (12 points).
6. The Mannich reaction is a reaction that substitutes the α-carbon of a ketone with an amine. Propose
a mechanism for the following Mannich reaction (8 points) O
H N+ +
7. Determine the major product for the following reactions. Include a complete reaction mechanism
with all appropriate stereochemistry (16 points).
a. O O
b. 1. O3, -78 °C
8. Complete the following roadmap problem by giving the structures if the missing compounds
2. DMS A B C
[(PPh3)CuH]6 = Stryker's Reagent
1. In chapter 19, we discussed a variety of condensation reactions (aldol, claisen, etc.). These reactions are powerful in that they form carbon-carbon bonds fairly easily. The Knoevenagel condensation is a related reaction to those other condensation reactions. The reaction involves the condensation of a β-dicarbonyl compound and an aldehyde. Predict the product of the following series of reactions where the second step is a Knoevenagel condensation (10 points).
2. benzaldehyde, H+
2. The reaction of an α-haloketone with sodium hydroxide produces a carboxylic acid in a reaction
known as the Favorskii rearrangement. The mechanism of the reaction includes the formation of an enolate followed by intramolecular nucleophilic addition. Using the below example, provide a mechanism for this reaction (15 points).
O H3C NaOH