Practice Problems Organic Chemistry II

Which of the following molecules is most stable?

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Answer explanation

The correct answer is (A)

Response (B) has 4 conjugated p –bonds.

Note that sp3-hybridized carbon atoms disrupt the conjugated system.

Response (C) has 2 sets of 3 conjugated p –bonds.

Note that sp3-hybridized carbon atoms disrupt the conjugated system.

Response (D) has 4 conjugated p –bonds.

Note that sp3-hybridized carbon atoms disrupt the conjugated system.

Response (A) has 6 conjugated p –bonds and is therefore the correct answer.

Note that sp3-hybridized carbon atoms disrupt the conjugated system.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

From the standpoint of reactivity, which is the best dienophile to react with the following diene in a Diels-Alder reaction?

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Answer explanation

The correct answer is (A)

For this question you recall that for a Diels-Alder reaction you want to match the electrostatics for the 2 reactants.

You want one to contain electron withdrawing groups (EWGs) while the other contains electron donating groups (EDGs).

The given diene has an EDG (the oxygen is d-) so we are looking for a response which has an EWG.

Which of the following is aromatic?

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Answer explanation

(B) the carbocation contains an empty P-orbital, and we count the electrons on the nitrogen. 6 p electrons that fills the HOMO and hence makes the molecule aromatic.

Which of the following is NOT a mechanistic step in the following hydrolysis reaction:

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Which starting material(s) would give the product shown below?

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Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-4

Which of the following amino acids is NOT one of the twenty common amino acids?

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Tags

NGSS.HS-LS1-6

Rank the following monomers in order of increasing reactivity in cationic polymerization:

• I < IV < II < III

• IV < II < III < I

• IV < I < III < II

• IV < I < II < III

The reaction of a secondary amine with acetone will lead to the formation of which of the following?

• imine

• amide

• oxime

• enamine

Which functional groups does a peptide bond contain?

• ester

• aromatic ring

• acetal

• amide

When you think of Green Chemistry, what comes to mind?

Tags

NGSS.HS-ETS1-3

NGSS.HS-LS2-7

NGSS.HS-PS1-6