Orgo Chem Exam 2
What is the IUPAC name for the following compound? -2-Bromo-4-pentylhexane -(2S,4S)-2-Bromo-4,5-diethylheptane -3,4-Diethyl-6-bromoheptane -2-Bromo-4-methylhexane -(2R,4R)-2-Bromo-4,5-diethylheptane
(2S,4S)-2-Bromo-4,5-diethylheptane
Which of the following is a tertiary alkyl halide? (CH3)2CHCH2Cl (CH3)2CClCH2CH3 (CH3)2CHCHClCH3 (CH3)2CHCH2CHClCH2CH3
(CH3)2CClCH2CH3
Which of the following is the correct IUPAC name of the following structure? (S)-3-ethyl-2-methylhexane (R)-3-ethyl-2-methylhexane (S)-3-ethyl-2-methylpentane (R)-3-ethyl-2-methylpentane
(R)-3-ethyl-2-methylhexane
Which of the following is the correct IUPAC name of the following structure?
(R)-3-methylheptane
Which of the following is the enthalpy change of the following reaction under standard conditions? -8 kJ/mol(not correct) +8 kJ/mol +222 kJ/mol +79 kJ/mol
+8 kJ/mol
Identify the relationship between these two structures. -Diastereomers -Enantiomers -The same compound -Unrelated compounds
-Diastereomers
What is the specific rotation of a sample of carvone that is an equal mixture of the R and S enantiomers? (R)- carvone has a specific rotation of −61. -61 64 0 61
0
Which of the following compounds will undergo rearrangement during solvolysis reaction? 3-iodo-5-methylheptane 3-iodo-2-methylheptane 3-iodo-3-methylheptane 3-iodoheptane cis-1-iodo-3-methylcyclohexane
3-iodo-2-methylheptane
How many distinct resonances would appear in the (proton-decoupled) 13C NMR spectrum for the following compound?
4
What is the specific rotation of pure (S)-carvone if a sample of (R)-carvone of 85% ee has a specific rotation of −54? −61 64 0 61
64
What is the percentage of the R enantiomer in a sample of carvone that has a specific rotation of −20, given that the specific rotation of (R)-carvone is −61?
66.5%
How many possible stereoisomers are there for Crestor ® (rosuvastatin), a medication used to reduce cholesterol?
8
What is a transition state? An isolable intermediate in a reaction. The starting materials of the reaction. A local maximum on the energy diagram. A low-energy point between the starting materials and the product.
A local maximum on the energy diagram.
What is an intermediate? A local maximum on the energy diagram. A point on the reaction pathway that has a discrete lifetime. A point half-way between the starting materials and products. The highest energy compound on an energy diagram.
A point on the reaction pathway that has a discrete lifetime.
What is wrong with the following mechanism? -There is no leaving group, so there should be no arrows. -The arrow should be removing a proton from the H2O group. -An arrow is also needed to indicate the loss of the leaving group. -The arrow is backwards.
An arrow is also needed to indicate the loss of the leaving group.
Identify the electrophilic site in the following molecule. C O B No electrophilic site (not correct)
B
Identify the electrophilic site in the following molecule. H C of carbonyl C other than carbonyl O of carbonyl
C of carbonyl
Which of the following is the electrophilic site in the reactants of the following reaction? C of the carbonyl O Li Me
C of the carbonyl
Why is the entropy change negative for ring closures? Closing a ring results in fewer molecules. Closing a ring results in more molecules. Closing a ring releases energy. Closing a ring restricts the rotation around individual carbon-carbon bonds.
Closing a ring restricts the rotation around individual carbon-carbon bonds.
What is the relationship between the following two compounds?
Constitutional Isomers
What is the relationship between the following two compounds? not isomers; different compounds entirely (not correct)
Constitutional Isomers
Which of the following would you expect to have the most negative ΔS? A B C D
D
What is the relationship of the following two structures?
Diastereomer
What is the relationship between the following two molecules?
Diastereomers
What is the relationship between the two structures shown? Same compound Diastereomers Enantiomers None of these
Diastereomers
What is the relationship of the following two structures?
Diastereomers
Which of the following strategies will NOT be an effective way to separate enantiomers?
Distillation
What substitution reaction mechanism is most likely for the following compound? SN1 SN2 Either SN1 or SN2 None of these
Either SN1 or SN2
Identify the relationship between the following two structures. Enantiomers Identical Neither
Enantiomers
What is the relationship between the following two molecules? Enantiomers Diastereomers Identical Constitutional Isomers
Enantiomers
Which of the following is a weakest nucleophile in a polar protic solvent? F- Cl- Br- I- All of these
F-
Which of the following potential energy diagram represent an exothermic concerted reaction? I II III IV
I
What is the nucleophile in the following reaction? I II III IV
II
Predict the product for the following reaction. I II III IV None of these
III
Which of the following is a mechanism for an SN2 reaction? I II III IV Both I & II
III
Identify the relationship between the following two structures
Identical
Identify the relationship between the following two structures. Enantiomers Identical Neither
Identical
Identify the relationship between the following two structures. Enantiomers Identical Neither (not correct)
Identical
What is the relationship between the following two compounds?
Identical
What is the relationship between the following two compounds? Constitutional isomers Stereoisomers Identical Not isomers; different compounds entirely.
Identical
What is the relationship between the following two molecules?
Identical
What is the relationship of the following two structures? Enantiomers Diastereomers Constitutional isomers Identical
Identical
The structure of Crestor (rosuvastatin), a medication used to reduce cholesterol, is shown below. If the specific rotation for this compound is known to be +100, what would be the specific rotation for the stereoisomer shown at the right? +100 -100 0 Impossible to predict
Impossible to predict
Which of the following describes the effect of a catalyst on a reaction? It lowers the free energy of the products. It makes the reactants less stable. It changes the equilibrium constant. It lowers the energy of activation.
It lowers the energy of activation.
For the following reaction step, indicate which pattern of arrow pushing it represents. Proton transfer Loss of leaving group Nucleophilic attack Rearrangement
Loss of leaving group
What pattern of curved arrow pushingis the second step of this reaction? Proton transfer (not correct) Loss of leaving group Nucleophilic attack Rearrangement
Loss of leaving group
Which of the following is the nucleophilic site in the reactants of the following reaction? C of the carbonyl (not correct) O Li Me of Li-Me
Me of Li-Me
For the following reaction step, indicate which pattern of arrow pushing it represents. Proton transfer Loss of leaving group Nucleophilic attack Rearrangement
Nucleophilic attack
What pattern of curved arrow pushing is the second step of this reaction? Proton transfer Loss of leaving group Nucleophilic attack Rearrangement
Nucleophilic attack
Identify the nucleophilic atom in the following molecule. Me3P P C H Me
P
For the following reaction step, indicate which pattern of arrow pushing it represents. Proton transfer Loss of leaving group Nucleophilic attack Rearrangement
Proton transfer
What pattern of curved arrow pushing is the fourth step of this reaction? Proton transfer Loss of leaving group Nucleophilic attack Rearrangement
Proton transfer
Identify the sequence of curved arrows (electron movement) in the steps of the following reaction. Proton transfer, proton transfer Proton transfer, loss of leaving group Nucleophilic attack, proton transfer Proton transfer, nucleophilic attack
Proton transfer, nucleophilic attack
Identify the sequence of curved arrows (electron movement) in the steps of the following reaction. -Proton transfer, proton transfer, nucleophilic Attack -Proton transfer, loss of leaving group -Nucleophilic attack, proton transfer, loss of leaving group -Proton transfer, nucleophilic attack, proton transfer
Proton transfer, nucleophilic attack, proton transfer
For the following reaction step, indicate which pattern of arrow pushing it represents. Proton transfer Loss of leaving group Nucleophilic attack Rearrangement
Rearrangement
What substitution reaction mechanism is most likely for the following conversion? SN1 SN2 Either SN1 or SN2 None of these
SN2
What is wrong with the following mechanism? -There is no leaving group, so there should be no arrows. -The arrow should be removing a proton from the H2O group. -An arrow is also needed to indicate the loss of the leaving group. -The arrow indicating the formation of the C-Br bond (nucleophilic attack) should start at the bromide anion.
The arrow indicating the formation of the C-Br bond (nucleophilic attack) should start at the bromide anion.
Identify the relationship between these two structures. Diastereomers Enantiomers The same compounds Unrelated compounds
The same compounds
Predict the sign of ΔG for an endothermic reaction with an increase in entropy. positive negative no change cannot predict without additional information
cannot predict without additional information
Predict the sign of ΔG for an exothermic reaction with a decrease in entropy. positive negative no change cannot predict without additional information
cannot predict without additional information
What type of bond cleavage does the following reaction involve? homolytic heterolytic
homolytic
Which of the following is a reasonable definition of a concerted reaction? -it is a reaction in which bond breaking occurs first -it is a reaction in which all bond-breaking and bond-forming occurs at the same time -it is a reaction in which bond forming occurs first -it is a substitution reaction
it is a reaction in which all bond-breaking and bond-forming occurs at the same time
Predict the sign of ΔG for an exothermic reaction with an increase in entropy. positive negative no change cannot predict without additional information
negative
Predict the sign of ΔS of the following reaction. positive negative no change
negative
Predict the sign of ΔS of the following reaction. positive negative no change (not correct)
negative
Predict the sign of ΔS of the following reaction. positive negative no change
positive
What set of reaction conditions would favor an SN2 reaction on 2-bromo-3-methylbutane? weak nucleophile in a protic solvent weak nucleophile in an aprotic solvent strong nucleophile in a protic solvent strong nucleophile in an aprotic solvent
strong nucleophile in an aprotic solvent
