![Organic Chemistry: Principles and Mechanisms (Second Edition)](https://www.bartleby.com/isbn_cover_images/9780393663556/9780393663556_smallCoverImage.jpg)
Concept explainers
(a)
Interpretation:
The specific type of relationship between the molecules in the given pair is to be determined.
Concept introduction:
If two molecules have different molecular formulas, they are unrelated. If they have the same molecular formula, they may be the same molecule or isomers. If the two can be interconverted by rotation about a bond, they are conformers. If they have different connectivity of atoms, they are constitutional isomers. If they have the same connectivity, but are not conformers, they must be stereoisomers. Stereoisomers may be enantiomers or diastereomers depending on whether they have nonsuperimposable mirror images or not.
![Check Mark](/static/check-mark.png)
Answer to Problem 5.71P
The two molecules are unrelated.
Explanation of Solution
Structures of the two molecules are:
Both molecules contain the same number of carbon atoms. However, their formulas are different. The first molecule contains a ring with all single bonds. Therefore it has an IHD of 1, and its molecular formula must be
Thus, these are different, unrelated molecules.
Two molecules are unrelated if they have different molecular formulas.
(b)
Interpretation:
The specific type of relationship between the molecules in the given pair is to be determined.
Concept introduction:
If two molecules have different molecular formulas, they are unrelated. If they have the same molecular formula, they may be the same molecule or isomers. If the two can be interconverted by rotation about a bond, they are conformers. If they have different connectivity of atoms, they are constitutional isomers. If they have the same connectivity, but are not conformers, they must be stereoisomers. Stereoisomers may be enantiomers or diastereomers depending on whether they have nonsuperimposable mirror images or not.
![Check Mark](/static/check-mark.png)
Answer to Problem 5.71P
The two molecules are constitutional isomers.
Explanation of Solution
The structures of the two molecules are:
Both molecules contain six carbon atoms. The first one contains a ring, while the second contains one double bond. They both have the same IHD of 1 and the same molecular formula
Therefore, they must be constitutional isomers.
Molecules with the same molecular formula but different connectivities are constitutional isomers.
(c)
Interpretation:
The specific type of relationship between the molecules in the given pair is to be determined.
Concept introduction:
If two molecules have different molecular formulas, they are unrelated. If they have the same molecular formula, they may be the same molecule or isomers. If the two can be interconverted by rotation about a bond, they are conformers. If they have different connectivity of atoms, they are constitutional isomers. If they have the same connectivity, but are not conformers, they must be stereoisomers. Stereoisomers may be enantiomers or diastereomers depending on whether they have nonsuperimpoable mirror images or not.
![Check Mark](/static/check-mark.png)
Answer to Problem 5.71P
The two molecules are unrelated.
Explanation of Solution
The structures of the molecules are:
Both have the same number of carbon atoms and also contain the same ring. However, they have different IHDs, and therefore, different molecular formulas. The first molecule contains only one ring, but no multiple bonds. Therefore, it has an IHD of 1 and a molecular formula of
Therefore, they are unrelated molecules.
Two molecules are unrelated if they have different molecular formulas.
(d)
Interpretation:
The specific type of relationship between the molecules in the given pair is to be determined.
Concept introduction:
If two molecules have different molecular formulas, they are unrelated. If they have the same molecular formula, they may be the same molecule or isomers. If the two can be interconverted by rotation about a bond, they are conformers. If they have different connectivity of atoms, they are constitutional isomers. If they have the same connectivity, but are not conformers, they must be stereoisomers. Stereoisomers may be enantiomers or diastereomers depending on whether they have nonsuperimposable mirror images or not.
![Check Mark](/static/check-mark.png)
Answer to Problem 5.71P
The molecules are unrelated.
Explanation of Solution
The structures of the molecules are:
The molecules have different number of carbon atoms, nine and eight, respectively.
Therefore, they are unrelated molecules.
Molecules with different molecular formulas are unrelated.
(e)
Interpretation:
The specific type of relationship between the molecules in the given pair is to be determined.
Concept introduction:
If two molecules have different molecular formulas, they are unrelated. If they have the same molecular formula, they may be the same molecule or isomers. If the two can be interconverted by rotation about a bond, they are conformers. If they have different connectivity of atoms, they are constitutional isomers. If they have the same connectivity, but are not conformers, they must be stereoisomers. Stereoisomers may be enantiomers or diastereomers depending on whether they have nonsuperimposable mirror images or not.
![Check Mark](/static/check-mark.png)
Answer to Problem 5.71P
The two molecules are enantiomers.
Explanation of Solution
The structures of the two molecules are:
The chemical formulas of both molecules are the same,
The nitrogen atom in each molecule is bonded to four different groups;
The specific relation between the two isomers can be determined from the configuration at the nitrogen atom.
The priorities of
In the first molecule, the 1 to 3 priority groups are arranged clockwise with the lowest priority H at the back. Therefore, the configuration at this nitrogen is R.
In the second molecule also, they are arranged clockwise, but with the lowest priority H in front. Therefore, the configuration at the nitrogen in second molecule is S.
Thus, they are enantiomer.
The molecules are enantiomers because they have different configurations and are the only chiral center.
(f)
Interpretation:
The specific type of relationship between the molecules in the given pair is to be determined.
Concept introduction:
If two molecules have different molecular formulas, they are unrelated. If they have the same molecular formula, they may be the same molecule or isomers. If the two can be interconverted by rotation about a bond, they are conformers. If they have different connectivity of atoms, they are constitutional isomers. If they have the same connectivity, but are not conformers, they must be stereoisomers. Stereoisomers may be enantiomers or diastereomers depending on whether they have nonsuperimposable mirror images or not.
![Check Mark](/static/check-mark.png)
Answer to Problem 5.71P
The two molecules are conformers.
Explanation of Solution
The structures of the molecules are:
The molecules have the same molecular formula and same connectivity. Therefore, they are either conformers or configurational isomers.
If rotation of one group in the first molecule about a single bond converts it to the other structure, then they must be conformers. If not, they would be configurational isomers.
Rotating C3 of first molecule about
Therefore, these two molecules are two conformers of the same molecule.
The two molecules are conformers as they differ from each other only by rotation about a single bond.
(g)
Interpretation:
The specific type of relationship between the molecules in the given pair is to be determined.
Concept introduction:
If two molecules have different molecular formulas, they are unrelated. If they have the same molecular formula, they may be the same molecule or isomers. If the two can be interconverted by rotation about a bond, they are conformers. If they have different connectivity of atoms, they are constitutional isomers. If they have the same connectivity, but are not conformers, they must be stereoisomers. Stereoisomers may be enantiomers or diastereomers depending on whether they have nonsuperimposable mirror images or not.
![Check Mark](/static/check-mark.png)
Answer to Problem 5.71P
The two molecules are enantiomers.
Explanation of Solution
Structures of the molecules are:
The molecules have the same formula and same connectivity. Therefore, they must be either conformers or configurational isomers. The exact relation between the two molecules can be determined from the configurations about the chiral centers in the two. Each molecule contains two chiral centers, C2 and C3.
The structures of both are shown with the lowest priority H atoms in the plane of the paper. Therefore, the molecules are rotated about the
The priorities of the four groups attached to C2 and C3 are then determined.
In the first molecule, on C2, chlorine is assigned the highest priority as it is the heaviest (highest
For C2, 1 to 3 priority groups are arranged clockwise with H at the back. On C3, 1 to 3 priority groups are arranged counterclockwise, but with H in the front. Therefore, the configurations are
A similar analysis shows that the configurations of the two chiral centers in second molecule are
Therefore, the two molecules are enantiomers.
Two molecules with multiple chiral centers are enantiomers if they have different configuration at each chiral center.
(h)
Interpretation:
The specific type of relationship between the molecules in the given pair is to be determined.
Concept introduction:
If two molecules have different molecular formulas, they are unrelated. If they have the same molecular formula, they may be the same molecule or isomers. If the two can be interconverted by rotation about a bond, they are conformers. If they have different connectivity of atoms, they are constitutional isomers. If they have the same connectivity, but are not conformers, they must be stereoisomers. Stereoisomers may be enantiomers or diastereomers depending on whether they have nonsuperimpoable mirror images or not. Molecules with multiple chiral centers are diastereomers if the configuration at some but not all centers is different.
![Check Mark](/static/check-mark.png)
Answer to Problem 5.71P
The two molecules are diastereomers.
Explanation of Solution
The structures of the molecules are:
The molecules have the same formulas and same connectivities. Therefore, they are stereoisomers. They are not interconverted by rotation about a single bond, therefore, they are not conformers.
The exact relation can then be determined from the configurations at the two chiral centers they contain.
The priorities assigned according to Cahn-Ingold-Prelog rules to the four groups on the chiral centers are as shown above.
In the first molecule, 1 to 3 priority groups on C2 are arranged clockwise with the lowest priority H at the back. 1 to 3 priority groups on C3 are arranged counterclockwise with the lowest priority H in the front. Therefore, the configurations of the chiral centers in the first molecule are
A similar analysis shows that the configurations of the chiral centers in the second molecule are
Therefore, these molecules are diastereomers.
Molecules containing multiple chiral centers are diastereomers if they differ in configuration at only some of the chiral centers.
Want to see more full solutions like this?
Chapter 5 Solutions
Organic Chemistry: Principles and Mechanisms (Second Edition)
- Nonearrow_forwardIn the solid state, oxalic acid occurs as a dihydrate with the formula H2C2O4 C+2H2O. Use this formula to calculate the formula weight of oxalic acid. Use the calculated formula weight and the number of moles (0.00504mol) of oxalic acid in each titrated unknown sample recorded in Table 6.4 to calculate the number of grams of pure oxalic acid dihydrate contained in each titrated unknown sample.arrow_forward1. Consider a pair of elements with 2p and 4p valence orbitals (e.g., N and Se). Draw their (2p and 4p AO's) radial probability plots, and sketch their angular profiles. Then, consider these orbitals from the two atoms forming a homonuclear л-bond. Which element would have a stronger bond, and why? (4 points)arrow_forward
- Write the reaction and show the mechanism of the reaction. Include the mechanism for formation of the NO2+ 2. Explain, using resonance structures, why the meta isomer is formed. Draw possible resonance structures for ortho, meta and para.arrow_forwardNonearrow_forward3. A molecular form of "dicarbon", C2, can be generated in gas phase. Its bond dissociation energy has been determined at 599 kJ/mol. Use molecular orbital theory to explain why energy of dissociation for C₂+ is 513 kJ/mol, and that for C2² is 818 kJ/mol. (10 points)arrow_forward
- 9.73 g of lead(IV) chloride contains enough Cl- ions to make ____ g of magnesium chloride.arrow_forward6. a) C2's. Phosphorus pentafluoride PF5 belongs to D3h symmetry group. Draw the structure of the molecule, identify principal axis of rotation and perpendicular (4 points) b) assume that the principal axis of rotation is aligned with z axis, assign symmetry labels (such as a1, b2, etc.) to the following atomic orbitals of the P atom. (character table for this group is included in the Supplemental material). 3s 3pz (6 points) 3dz²arrow_forward2. Construct Lewis-dot structures, and draw VESPR models for the ions listed below. a) SiF5 (4 points) b) IOF4 (4 points)arrow_forward
- 5. Complex anion [AuCl2]¯ belongs to Doh symmetry point group. What is the shape of this ion? (4 points)arrow_forward4. Assign the following molecules to proper point groups: Pyridine N 1,3,5-triazine N Narrow_forward7. a) Under normal conditions (room temperature & atmospheric pressure) potassium assumes bcc lattice. Atomic radius for 12-coordinate K atom is listed as 235 pm. What is the radius of potassium atom under normal conditions? (3 points) b) Titanium metal crystallyzes in hcp lattice. Under proper conditions nitrogen can be absorbed into the lattice of titanium resulting in an alloy of stoichiometry TiNo.2. Is this compound likely to be a substitutional or an interstitial alloy? (Radius of Ti (12-coordinate) is 147 pm; radius of N atom is 75 pm. (3 points)arrow_forward
- Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage LearningChemistry for Today: General, Organic, and Bioche...ChemistryISBN:9781305960060Author:Spencer L. Seager, Michael R. Slabaugh, Maren S. HansenPublisher:Cengage Learning
![Text book image](https://www.bartleby.com/isbn_cover_images/9780618974122/9780618974122_smallCoverImage.gif)
![Text book image](https://www.bartleby.com/isbn_cover_images/9781305960060/9781305960060_smallCoverImage.gif)