Concept explainers
(a)
Interpretation:
The configuration of each of the asymmetric centers in the given compound is to be determined.
Concept introduction:
Asymmetric center is a stereocenter which arises to a compound if any atom is bonded to four different groups.
Stereoisomers are named by following Cahn-Ingold-Prelog system, in which R or S letter is used to differentiate between enantiomers.
According to Cahn-Ingold-Prelog system,
The group attached to asymmetric center should be ranked based on the
Check the direction of arrow drawn in the direction of decreasing priority. If the arrow points clockwise direction, then the compound has R configuration. If the arrow points counterclockwise direction, then the compound has S configuration. If the group with lowest priority is not bonded by a hatched wedge, then interchange this group (lowest priority) by group bonded to hatched wedge and draw the arrow in priority order but the configuration is assigned as just reverse.
(b)
Interpretation:
The configuration of each of the asymmetric centers in the given compound is to be determined.
Concept introduction:
Asymmetric center is a stereo center which arises to a compound if any atom is bonded to four different groups.
Stereoisomers are named by following Cahn-Ingold-Prelog system, in which R or S letter is used to differentiate between enantiomers.
According to Cahn-Ingold-Prelog system,
The group attached to asymmetric center should be ranked based on the atomic number of atom which directly connected to asymmetric center. The higher the atomic number of atom, higher the priority. If there is tie, then consider the next atoms attached to the connected atom and so on.
For Fischer projection formula: Check the direction of arrow drawn in the direction of decreasing priority. If the arrow points clockwise direction, then the compound has R configuration. If the arrow points counterclockwise direction, then the compound has S configuration. If the group with lowest priority is bonded in horizontal line, then the configuration is assigned as just reverse.
(c)
Interpretation:
The configuration of each of the asymmetric centers in the given compound is to be determined.
Concept introduction:
Asymmetric center is a stereocenter which arises to a compound if any atom is bonded to four different groups.
Stereoisomers are named by following Cahn-Ingold-Prelog system, in which R or S letter is used to differentiate between enantiomers.
According to Cahn-Ingold-Prelog system,
The group attached to asymmetric center should be ranked based on the atomic number of atom which directly connected to asymmetric center. The higher the atomic number of atom, higher the priority. If there is tie, then consider the next atoms attached to the connected atom and so on.
For Fischer projection formula: Check the direction of arrow drawn in the direction of decreasing priority. If the arrow points clockwise direction, then the compound has R configuration. If the arrow points counterclockwise direction, then the compound has S configuration. If the group with lowest priority is bonded in horizontal line, then the configuration is assigned as just reverse.
(d)
Interpretation:
The configuration of each of the asymmetric centers in the given compound is to be determined.
Concept introduction:
Asymmetric center is a stereocenter which arises to a compound if any atom is bonded to four different groups.
Assigning of configuration for carbohydrates, the configuration is R if –OH group is on the right and the configuration is S if the –OH is group in on left side.
(e)
Interpretation:
The configuration of each of the asymmetric centers in the given compound is to be determined.
Concept introduction:
Asymmetric center is a stereocenter which arises to a compound if any atom is bonded to four different groups.
Stereoisomers are named by following Cahn-Ingold-Prelog system, in which R or S letter is used to differentiate between enantiomers.
According to Cahn-Ingold-Prelog system,
The group attached to asymmetric center should be ranked based on the atomic number of atom which directly connected to asymmetric center. The higher the atomic number of atom, higher the priority. If there is tie, then consider the next atoms attached to the connected atom and so on.
For Fischer projection formula: Check the direction of arrow drawn in the direction of decreasing priority. If the arrow points clockwise direction, then the compound has R configuration. If the arrow points counterclockwise direction, then the compound has S configuration. If the group with lowest priority is bonded in horizontal line, then the configuration is assigned as just reverse.
Conversion of sawhorse projection to Fischer projection,
The groups on the front side carbon of sawhorse projection - The groups on the bottom side carbon of Fischer projection. And the groups on the back side carbon of sawhorse projection - The groups on the topside carbon of Fischer projection
The groups on the vertical line of sawhorse projection are the groups on the vertical line of Fischer projection.
The groups on the left side of sawhorse projection are the groups on the left side of horizontal line of Fischer projection.
The groups on the right side of sawhorse projection are the groups on the right side of horizontal line of Fischer projection.
(f)
Interpretation:
The configuration of each of the asymmetric centers in the given compound is to be determined.
Concept introduction:
Asymmetric center is a stereocenter which arises to a compound if any atom is bonded to four different groups.
Stereoisomers are named by following Cahn-Ingold-Prelog system, in which R or S letter is used to differentiate between enantiomers.
According to Cahn-Ingold-Prelog system,
The group attached to asymmetric center should be ranked based on the atomic number of atom which directly connected to asymmetric center. The higher the atomic number of atom, higher the priority. If there is tie, then consider the next atoms attached to the connected atom and so on.
Check the direction of arrow drawn in the direction of decreasing priority. If the arrow points clockwise direction, then the compound has R configuration. If the arrow points counterclockwise direction, then the compound has S configuration. If the group with lowest priority is not bonded by a hatched wedge, then interchange this group (lowest priority) by group bonded to hatched wedge and draw the arrow in priority order but the configuration is assigned as just reverse.
Newman projection: Newman projection of molecule is one type of representations for the
From the angle of observer the front carbon is proximal and second carbon is distal.
In wedge-dash line representation wedge is coming out of the plane and going behind the plane, the wedge and the dash of front carbon in Newman projection are pointing up and the wedge and the dash of back carbon in Newman projection are pointing down.
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Chapter 4 Solutions
Organic Chemistry; Organic Chemistry Study Guide A Format: Kit/package/shrinkwrap
- Part B. Mark each chirality center in each molecule with an asterisk (*). Illustrate onto the image Cannot be hand-drawnarrow_forwardDetermine the configuration of each stereogenic center in the compound below. Highlight the carbon in red if the configuration is R, and in blue if the configuration is S.arrow_forwardLocate the tetrahedral stereogenic center(s) in each compound. A molecule may have one or more stereogenic centers.arrow_forward
- The [α] of pure quinine, an antimalarial drug, is −165. a.Calculate the ee of a solution with the following [α] values: −50, −83, and −120. b. For each ee, calculate the percent of each enantiomer present. c.What is [α] for the enantiomer of quinine? d. If a solution contains 80% quinine and 20% of its enantiomer, what is the ee of the solution? e. What is [α] for the solution described in part (d)?arrow_forwardDraw both enantiomers for the attached biologically active compound.arrow_forward(a) Which compounds (B–F) are identical to A? (b) Which compounds (B–F) represent an isomer of A?arrow_forward
- Consider the following six compounds (A–F). How are the two compounds in each pair related? Choose from enantiomers, epimers, diastereomers but not epimers, constitutional isomers, and identical compounds.a. A and Bb. A and Cc. B and Cd. A and De. E and Farrow_forwardDraw both enantiomers for each biologically active compound.arrow_forwardDraw the structure for a compound with molecular formula C2H2I2F2 a. that is optically inactive because it does not have an asymmetric center. b. that is optically inactive because it is a meso compound. c. that is optically active.arrow_forward
- Citalopram is an antidepressant pharmaceutical that is sold as a racemic mixture. However, it is known that the (S) enantiomer is 30x more biologically active than the (R) enantiomer. Draw the (S) configuration.arrow_forwardHow many asymmetric centers in naproxenarrow_forwardDraw all possible configurational stereoisomers for the given molecule below. Designate the R/S on the stereogenic centers and E/Z on the C=Carrow_forward
