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CHEM103: Organic Chemistry I

Unit 6: Alkenes   Alkenes are hydrocarbons with carbon-carbon double bonds.  Alkenes are also known as ‘olefins’ which means ‘oil forming gas’.  Many important alkenes are found in plants and animals as well as in industrial compounds. ‘Ethylene’, for example, is the largest-volume organic compound produced.  The alkene reactions you will learn about here will serve as the basis for understanding the more complex reactions you will encounter later in the course and in more advanced courses, such as pharmaceutical and medicinal chemistry.  You should make sure you understand the rationale and mechanisms behind the reactions listed prior to moving on, as they are extremely important!

Unit 6 Time Advisory
This unit will take you up to 19.25 hours to complete.

☐    Subunit 6.1: 7.5 hours

☐    Sub-subunit 6.1.1: 2.25 hours

☐    Sub-subunit 6.1.2: 3.75 hours

☐    Sub-subunit 6.1.3: 1.5 hours

☐    Subunit 6.2: 11.75 hours

☐    Sub-subunit 6.2.1:  0.5 hour   

☐    Sub-subunit 6.2.2:  0.75 hour               

☐    Sub-subunit 6.2.3:  0.5 hour   

☐    Sub-subunit 6.2.4:  0.5 hour   

☐    Sub-subunit 6.2.5:  0.5 hour   

☐    Sub-subunit 6.2.6:  0.5 hour   

☐    Sub-subunit 6.2.7:  0.5 hour   

☐    Sub-subunit 6.2.8:  0.5 hour   

☐    Sub-subunit 6.2.9:  0.5 hour   

☐    Sub-subunit 6.2.10: 0.5 hour  

☐    Sub-subunit 6.2.11: 0.5 hour  

☐    Sub-subunit 6.2.12: 0.5 hour  

☐    Sub-subunit 6.2.13: 2.25 hours          

☐    Sub-subunit 6.2.14: 1.75 hours

☐    Sub-subunit 6.2.15: 1.5 hour 

Unit6 Learning Outcomes
Upon successful completion of this unit, the student will be able to:

  • Derive the name of alkenes from their molecular structure and vice versa. 
  • Understand the difference between cis and tran isomers.
  • Draw conformational isomers and assign the proper notation (E/Z, etc.).
  • Calculate the degree of unsaturation.
  • Describe alkene synthesis from alcohols and typical reactions with an emphasis on the reaction mechanism for the addition of electrophilic reagents to the carbon-carbon double bond.  

6.1 Nomenclature, Structural and Physical Properties   6.1.1 Alkene Nomenclature   - Web Media: Khan Academy: Salman Khan’s “Naming Alkenes Examples” Link: Khan Academy: Salman Khan’s: “Naming Alkenes Examples” (HTML)
 
Instructions: Please watch the video about the nomenclature of alkenes (8:27 minutes).  

 Terms of Use: This resource is licensed under a [Creative Commons
Attribution-NonCommercial-NoDerivs 3.0 Unported
License](http://creativecommons.org/licenses/by-nc-nd/3.0/). It is
attributed to the Khan Academy.
  • Reading: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Nomenclature of Alkenes” and “Nomenclature of Alkene Stereoisomers" Link: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Nomenclature of Alkenes” (HTML) and “Nomenclature of Alkene Stereoisomers" (HTML)

    Instructions: Read these webpages to learn how to name alkenes. 
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.  

  • Web Media: YouTube: ChemII Pickens’ “Naming Alkenes Part 1” and “Naming Alkenes Part 2” Links: YouTube: ChemII Pickens’ “Naming Alkenes Part 1” (YouTube) and “Naming Alkenes Part 2” (YouTube)
     
    Instructions: Watch these two videos (8-10 minutes each) to understand alkenes nomenclature. 
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.  

  • Assessment: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: "Drawing and Naming Alkene Stereoisomers” Link: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Drawing and Naming Alkene Stereoisomers” (HTML)
     
    Instructions: In the short section titled "Practice Problems," there is a scroll down menu with several problem topics.  Select "Drawing and Naming Alkene Stereoisomers,” and practice on all problems.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.  

6.1.2 Alkene Configurational Isomers   - Reading: University of Texas: Professor Nathan L. Bauld’s “Alkenes I: Properties of Alkenes” Link: University of Texas: Professor Nathan L. Bauld’s “Alkenes I: Properties of Alkenes” (HTML)

 Instructions: From the table of contents, select and read
“Cis/Trans Isomerism in Alkenes” and “E,Z System of Alkene
Nomenclature.”  This resource also covers the topics outlined in
subunits 6.1.2.1 through 6.1.2.2.  
    
 Terms of Use: Please respect the copyright and terms of use
displayed on the webpages above.  
  • Web Media: YouTube: ChemII Pickens’ “Cis and Trans Isomers in Alkenes” Link: YouTube: ChemII Pickens’ “Cis and Trans Isomers in Alkenes” (YouTube)
     
    Instructions: Watch the 5-minute video to understand cis- and trans-isomerism.  This resource also covers subunits 6.1.2.1 through 6.1.2.2.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.  

  • Assessment: Elmhurst College, Illinois: Virtual Chembook: “Cis-Trans Isomers of Alkenes” Link: Elmhurst College, Illinois: Virtual Chembook: “Cis-Trans Isomers of Alkenes” (HTML)
     
    Instructions: Read the webpage and complete the quiz at the bottom of the page (note that you can check your answers).  This resource covers subunits 6.1.2.1 through 6.1.2.2.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.  

  • Web Media: Khan Academy: Salman Khan’s “Cis-Trans and E,Z Naming Scheme for Alkenes” and “Entgegen-Zusammen Naming Scheme for Alkenes Examples” Link: Khan Academy: Salman Khan’s: “Cis-Trans and E,Z Naming Scheme for Alkenes” (HTML) and “Entgegen-Zusammen Naming Scheme for Alkenes Examples” (HTML)
     
    Instructions: Please watch these two videos, which explain the cis-trans and E,Z nomenclature of alkenes (11:00 minutes).  

    Terms of Use: These resources are licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. Thy are attributed to the Khan Academy.

6.1.2.1 Cis/trans isomerism   6.1.2.2 E/Z notation   6.1.3 Degree of Unsaturation   - Reading: University of California, Davis: UC Davis ChemWiki: "Degree of Unsaturation" Link: University of California, Davis: UC Davis ChemWiki: "Degree of Unsaturation” (HTML or PDF)
 
Instructions: Read the webpage, and complete the practice problems located toward the end of the page.  Note that calculating the degree of unsaturation is important when you elucidate the structure of a molecule, derive and draw a molecule from its chemical formula, and later deduce the structure of a molecule from the spectroscopy data. 
 
Note: You can view this in a PDF by clicking the “Make PDF” button near the top of the linked webpage.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.  

  • Web Media: YouTube: EnderlePhD’s “Degree of Unsaturation” Link: YouTube: EnderlePhD’s “Degree of Unsaturation” (YouTube)
     
    Instructions: Watch the video (10 minutes) to understand how to calculate the degree of unsaturation.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above. 

6.2 Synthesis and Reactivity   - Reading: University of California, Davis: UC Davis ChemWiki: "Alkenes" Link: University of California, Davis: UC Davis ChemWiki: "Alkenes” (HTML or PDF)
 
Instructions: In the table of contents, select the following reactions and read the corresponding material: “Alkenes by Dehydration of Alcohols,” “Catalytic Hydrogenation of Alkenes,” “Catalytic Hydrogenation of Alkenes: Relative Stability of Double Bonds,” “Diazomethane, Carbenes, and Cyclopropane Synthesis,” “Electrophilic Addition of Halogens to Alkenes,” “Electrophilic Addition of Hydrogen Halides,” “Hydroboration Oxidation,” “Oxacyclopropane Synthesis,” “Ozonolysis,” “Radical Additions: Anti-Markovnikov Product Formation,” “Radical Allylic Halogenation,” and “Vicinal Syn Dihydroxylation.”  This resource also covers the topics outlined in subunits 6.2.1 through 6.2.12.
 
Note: These are all available as a PDF by clicking the “Make PDF” button near the top of each page.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.  

6.2.1 Alkene Synthesis by Dehydration of Alcohols   6.2.2 Catalytic Hydrogenation of Alkenes   6.2.3 Catalytic Hydrogenation of Alkenes: Relative Stability of Double Bonds   6.2.4 Diazomethane, Carbenes, and Cyclopropane Synthesis   6.2.5 Electrophilic Addition of Halogens to Alkenes   6.2.6 Electrophilic Addition of Hydrogen Halides   6.2.7 Hydroboration Oxidation   6.2.8 Oxacyclopropane Synthesis   6.2.9 Ozonolysis   6.2.10 Radical Additions: Anti-Markovnikov Product Formation   6.2.11 Radical Allylic Halogenation   6.2.12 Vicinal Syn Dihydroxylation   6.2.13 Addition Reactions of Alkenes Part I   - Reading: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Addition Reactions of Alkenes Part I,” “Addition Reactions of Alkenes Part II,” and “Free Radical Reactions of Alkenes” Links: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Addition Reactions of Alkenes Part I,”  (HTML) “Addition Reactions of Alkenes Part II,” (HTML) and “Free Radical Reactions of Alkenes” (HTML)
 
Instructions: Read the entirety of these three sections, taken from the Virtual Textbook of Organic Chemistry, which discuss alkenes’ reactivity.  This resource covers subunits 6.2.13 through 6.2.15.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpages above. 

  • Web Media: YouTube: ChemII Pickens’ “Reactions of Alkenes” Link: YouTube: ChemII Pickens’ “Reactions of Alkenes” (YouTube)
     
    Instructions: Watch the brief 9-minute video that summarizes the most common reactions of alkenes.  This resource covers subunits 6.2.13 through 6.2.15.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.  

  • Assessment: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Reactions of Alkenes Part II: Practice Problems” Link: Michigan State University: Professor William Reusch’s Virtual Textbook of Organic Chemistry: “Reactions of Alkenes Part II: Practice Problems” (HTML)
     
    Instructions: Select and complete all the problems from the scroll-down menu.  These problems are taken from the Virtual Textbook of Organic Chemistry.  This resource covers subunits 6.2.13 through 6.2.15.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpages above.  

6.2.14 Addition Reactions of Alkenes Part II   6.2.15 Free Radical Reactions of Alkenes