Ch. 5 - ChiralityWorksheetSee all chapters
All Chapters
Ch. 1 - A Review of General Chemistry
Ch. 2 - Molecular Representations
Ch. 3 - Acids and Bases
Ch. 4 - Alkanes and Cycloalkanes
Ch. 5 - Chirality
Ch. 6 - Thermodynamics and Kinetics
Ch. 7 - Substitution Reactions
Ch. 8 - Elimination Reactions
Ch. 9 - Alkenes and Alkynes
Ch. 10 - Addition Reactions
Ch. 11 - Radical Reactions
Ch. 12 - Alcohols, Ethers, Epoxides and Thiols
Ch. 13 - Alcohols and Carbonyl Compounds
Ch. 14 - Synthetic Techniques
Ch. 15 - Analytical Techniques: IR, NMR, Mass Spect
Ch. 16 - Conjugated Systems
Ch. 17 - Aromaticity
Ch. 18 - Reactions of Aromatics: EAS and Beyond
Ch. 19 - Aldehydes and Ketones: Nucleophilic Addition
Ch. 20 - Carboxylic Acid Derivatives: NAS
Ch. 21 - Enolate Chemistry: Reactions at the Alpha-Carbon
Ch. 22 - Condensation Chemistry
Ch. 23 - Amines
Ch. 24 - Carbohydrates
Ch. 25 - Phenols
Ch. 26 - Amino Acids, Peptides, and Proteins

According to IUPAC protocol, each molecule must have a unique, unambiguous name – even stereoisomers.

Concept #1: Why stereoisomers need their own naming system.  

Rules for the R and S Naming System

Step 1: Assign priorities to the four atoms on the chiral center according to their atomic mass on the periodic table. 

Concept #2: R and S Naming- Step 1  

Step 2: When there is a tie between atomic weights, compare the next set of adjacent atoms (playoffs!)

Concept #3: R and S Naming- Step 2  

Step 3: Double bonds count twice. Triple bonds count three times

Concept #4: R and S Naming- Step 3  

Example #1: Determine priorities for the following chiral center.

Example #2: Determine priorities for the following chiral center.

Step 4: If the last priority group is in the back, then trace a path from highest to lowest priority

- Clockwise = R, Counterclockwise = S                            

- Always Ignore group 4

Concept #5: R and S Naming- Step 4  

Step 5: If the last priority group is NOT in the back, swap that group with the group that is on the dash.

- Trace path as always, but this time swap the sign since you swapped groups.

  • R becomes S
  • S becomes R

Concept #6: R and S Naming- Step 5  

Provide the full name of the following molecule including R & S. 

Practice: Provide the full name for the following molecule, taking stereochemistry into account.

Provide the full name of the following molecule including R & S. 

Practice: Provide the full name for the following molecule, taking stereochemistry into account.

Provide the full name of the following molecule including R & S. 

Practice: Provide the full name for the following molecule, taking stereochemistry into account.

Additional Problems
Identify the configuration of each chirality center in the following compounds:
Identify the configuration of each chirality center in the following compounds:
Identify the configuration of each chirality center in the following compounds:
Identify the configuration of each chirality center in the following compounds:
Which of the following is the acceptable structure for ( R )-5-bromohept-2-yne?
Give the IUPAC name, including stereochemistry of the compound below
Assign (R) or (S) configuration to the chiral center in each molecule.      
Give the IUPAC name, including stereochemistry of the compound below
Draw the following molecule. (1S,3S,4S)- 4-fluoro-3-methylcyclohexan-1-ol
Draw the structure of the following molecules. Make sure your strucuture show s the stereochemistry of the alkene.  (S)–2,2–dibromo–1,4–nonanediol
Meropenem is an injectable, broad spectrum antibiotic that is frequently used for the treatment of bacterial meningitis and pneumonia. The line-angle structure of Meropenem given below is drawn in a manner that shows the absolute stereochemistry clearly and unambiguously. This molecule contains several chiral centers, three of which are labeled 13, 14, and 15. The one alkene double bond present is labeled 19.
What is the absolute configuration of the chiral carbon shown below?  The absolute configuration is ______________
Name the following compounds
(R)-Limonene is found in many citrus fruits, including oranges and lemons: 
(R)-Limonene is found in many citrus fruits, including oranges and lemons: 
(R)-Limonene is found in many citrus fruits, including oranges and lemons: 
Write an acceptable IUPAC name for the following two molecules. Where appropriate, use E and Z or R and S.
Provide a name for the following pure compound. Be sure to name stereoisomers properly, designating configurations when necessary.
Assign the correct IUPAC name to the following structure (include any stereochemistry)
Assign the follow chiral centers as R or S.  Show your logic by drawing the groups around a circle & assigning priority.
Configurational isomers. Assign the follow chiral centers as R or S.  Show your logic by drawing the groups around a circle & assigning priority.
Assign the follow chiral centers as R or S.  Show your logic by drawing the groups around a circle & assigning priority.
Configurational isomers. Assign the follow chiral centers as R or S.  Show your logic by drawing the groups around a circle & assigning priority.
Examine the following structures. For each molecule with a chiral center, assign the stereochemistry then write "R" or "S" as appropriate in the box provided below each structure. For all molecules that have no chiral centers, leave the box blank.
The Cahn-Ingold-Prelog stereochemical designations used for the following substance are: a. (1S, 2R, 3R) b. (1R, 2R, 3R) c. (1R, 2S, 3R) d. (1S, 2S, 3S) e. (1R, 2S, 3S)
Which molecule has the R configuration?
The absolute configuration of the two carbon atoms in this compound are  a) R - left carbon atom; R - right carbon atom. b) S - left carbon atom; S - right carbon atom. c) S - left carbon atom; R - right carbon atom. d) R - left carbon atom; S - right carbon atom. 
Assign (R) or (S) configuration to the chiral center in each molecule.
Provide a structural formula for (R)-oct-7-en-3-ol. Be sure to designate each configuration properly for this single stereoisomer. You may give any acceptable type of structural formula.
Name the compound given below.
Draw the molecule using bondline structure. (4S,5R)-4,5-dimethylhept-1-yne
Give the proper IUPAC name that corresponds to the following structure.
Shown below are chemical structures of an anti-cholesterol medication Crestor (left) and a narcotic analgesic hydrocodone, also known as Vicodin (right). Label the stereocenters indicated by arrows with appropriate (R) or (S) designators. Note that the question asks for configurations of only 3 out of 4 stereocenters in Vicodin.
Assign the Cahn-Ingold-Prelog priorities directly on each structure and determine the R/S configuration. 
Draw the structure for the following IUPAC name. (2R,3S)-2-chloro-3-methylheptane
(2S,3R)-2-Bromo-3-methylpentane is
Determine the R/S configuration of the following alkane. If there is no chiral center put an X. (Hint: Think about the definition of a chiral center)
Assign configuration for the following compound (Adrenaline) and draw its enantiomer.
Assign the priority to the four groups attached to the chiral center compounds A and B. Then assign R and S configuration to the chiral center of molecules A and B.
Applying the correct rules for IUPAC nomenclature, select the correct name for the following compound. Make sure to include correct stereochemistry when appropriate. A) (R,Z)-6-fluorohex-4-en-3-ol B) (S,Z)- 6-fluorohex-4-en-3-ol C) (R,Z)- 7-fluorohept-5-en-3-ol D) (S,Z)- 7-fluorohept-5-en-3-ol
Name the following compound correctly using accurate  R or S and E and Z nomenclature.
Applying the correct rules for IUPAC nomenclature, select the correct name for the following compound. Make sure to include correct stereochemistry when appropriate. A) (R,Z)-3-chloropent-4-en-1-yne B) (R,Z)-3-chlorohex-2-en-5-yne C) (S,Z)-3-chlorohex-2-en-5-yne D) (S,Z)-3-chlorohex-4-en-1-yne E) (R,Z)-3-chlorohex-4-en-1-yne
For the following compound. a) Identify absolute configurations of all chirality centers. b) Draw its enantiomer
Assign the following chiral center as R or S. Show your logic by drawing the groups around a circle & assigning priority.
(R)-(3-Chloro-2-methylpropyl) methyl ether (A) on reaction with azide ion (N 3-) in aqueous ethanol gives (S)-(3-azido-2-methylpropyl) methyl ether (B). Compound A has the structure ClCH2CH(CH3)CH2OCH3. (a) Draw wedge–dashed wedge–line formulas of both A and B.  
Determine the R and S configuration of the following compound. 
Determine the R and S configuration of the following compound. 
Determine the R and S configuration of the following compound. 
Determine the R and S configuration of the following compound.
Albuterol, shown here, is a commonly prescribed asthma medication. For either enantiomer of albuterol, draw a three-dimensional formula using dashes and wedges for bonds that are not in the plane of the paper. Choose a perspective that allows as many carbon atoms as possible to be in the plane of the paper, and show all unshared electron pairs and hydrogen atoms (except those on the methyl groups labeled Me). Specify the (R,S) configuration of the enantiomer you drew.  
Designate the (R) or (S ) configuration at each chirality center in the following molecules.  
Shown below are Newman projection formulas for (R,R)-, (S,S)-, and (R,S)-2,3-dichlorobutane. (a) Which is which?  
Draw the following compounds.  a)  (S) – 2, 2 – dibromo – 1,4 – nonanediol           b)  (2R,3S)–3–bromo-2-butanol            c)  (R)–1,2–dibromobutane            d)  (S)–3–methyl-1-hexene 
The 3 stereocenters in penicillin V, a broad spectrum antibiotic, are labeled “a,” “b,” and “c” in the structure shown below. In each part of this question, the four bonds to the stereocenter are reproduced in the same orientation as they are written in this structure. Assign priorites to each of the four groups attached to the stereocenter (1 = highest priority; 4 = lowest priority), and write the number associated with each group in the appropriate circle. Then, determine whether the absolute stereochemical configuration is (R) or (S). θ
Name the following compound. 
Which of the following is the correct structure for the compound ( R)-2-pentanol?    
Identify the configuration of each chirality center in the following compounds:
Identify the configuration of each chirality center in the following compounds:
For each of the single, pure compounds given to the right, provide a name. Be sure to designate R/S and E/Z when necessary
The other half of the 2015 Nobel Prize in Medicine  was won by Youyou Tu. Youyou Tu discovered Artemisinin, a drug that has significantly reduced the mortality rates for patients suffering from Malaria.  a. List your priorities (1, 2, 3 etc.) in the boxes provided surrounding the chiral centers indicated with a black dot (·) and determine if each is either R or S.    
Provide a structural formula for (S)-3,6-dimethyl-3,4-octadiene. Note that any correct form of a structural formula is acceptable. Be sure to identify stereoisomers properly.
For the following IUPAC names, draw the appropriate line angle drawing (you can ignore R and S for the first two, but not the bottom one).
Which structure corresponds to (1R-2S-3S)-1,2-dibromo-3-ethylcyclohexane?
Designate the chiral center in the following molecule as either R or S.
Designate the chiral center in the following molecule as either R or S.
Designate the chiral center in the following molecule as either R or S.
Designate the chiral center in the following molecule as either R or S.
Draw the  Fischer projections  for the stereoisomers of 2-bromo-3-chlorobutane:CH3CHBrCHClCH3Clearly label pairs of enantiomers & diastereomers, if any. Drawings must be clear & correctly labeled. (You do NOT need to name the compounds)
Give an IUPAC substitutive name for each of the following molecules. Use E/Z or R/S as needed to properly indicate stereochemistry
Designate the (R) or (S ) configuration at each chirality center in the following molecules.
Designate the (R) or (S ) configuration at each chirality center in the following molecules.
Designate the (R) or (S ) configuration at each chirality center in the following molecules.
Draw the structure for (R,E)-5-bromo-6-methyloct-4-en-7-yn-4-ol
Label the chiral center of the following molecules as either R or S.
Draw the appropriate line angle drawing for the following IUPAC name.   (2S,6S)-1-bromo-1,2,6-trimethylcyclohexane
Assume that the four groups below are bonded to a stereocenter and assign an R.S system priority from 1 (highest) to 4 (lowest) to each of them. 
Select the Complete IUPAC name for the following compound, including the correct (R) or (S) designation.(S)-3-methylhexane (S)-4-methylhexane (R)-2-ethylpentane (R)-3-methylhexane
Arrange the following groups in order of decreasing priority that would allow you to determine E/Z, or R/S. a) -CH3 b) -CH2OH c)  -CH2NH2 d) -CH2 Br Provide a string of letters (e.g. abcd) as an answer with the highest priority listed first, lowest priority last: Arrange the following groups in order of decreasing priority that would allow you to determine E/Z, or R/S. a) -OCH3 b) -CH(CH3)2 c) -B(CH2CH3)2 d) -H Provide a string of letters (e.g. abcd) as an answer with the highest priority listed first, lowest priority last: 
Click the "draw structure" button to launch the drawing utility.Give the structure corresponding to the name. (2R,3S)-3-isopropyl-2-hexanol
How would you name the compound below? (A) (R)-3-bromo-3-methylhexane (B) (S)-3-bromo-3-methylhexane (C) (R)-2-bromo-2-ethylpentane (D) (S)-2-bromo-2-ethylpentane
Indicate the stereochemical configuration for the tetrahedral centers shown below.
Spell out the full name of the compound. 
What is the correct name for the following structure? Select one: a. (2R, 3R)-3-bromo-4-methylpentan-2-ol b. (2S, 3R)-3-bromo-4-methylpentan-2-ol c. (2S, 3S)-3-bromo-4-methylpentan-2-ol d. (2R, 3S)-3-bromo-4-methylpentan-2-ol 
Select the correct (R) or (S) designation for the stereocenter carbon atom in the following molecule.
Assume that the four groups below are bonded to a stereocenter and assign an R.S system priority from 1 (highest) to 4 (lowest) to each of them.
Select the proper IUPAC name for the following compound, including the (R) or (S) designation where appropriate. 
Select the complete IUPAC name for the following compound, including the correct (R) or (S) designation. 
Assign R or S to the indicated chiral center in the molecule below.
Click the "draw structure" button to launch the drawing utility.Give the structure corresponding to (S) 4-chloropent 2 yne.