Reading Guide 9-5 9-6 9-8 PDF

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exam 4...

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Sections 9.5-9.6, 9.8 Chapter 9 Skills (Learning Objectives on Blackboard): 9-13 End-of-Chapter Problems: 60, 62, 67, 73, 81-83 These sections cover three more electrophilic addition reactions. Two of the three reactions in these sections have a common synthetic theme in that they produce alcohols. Two of the three reactions in these sections have a common mechanistic theme in that proceed through a cationic three-membered ring intermediate. The opening of the rings by nucleophiles is similar and predictable – and we will see other similar reactions in later chapters. An understanding of the regiochemical and stereochemical preferences of the ring opening is critical. Continue to keep track of both the regiochemical and stereochemical consequences (is it selective, specific, neither) of each reaction. It is important to recognize that the words SYN and ANTI are mechanistic designations that describe how the addition is done, not necessarily the structure of the final product (recall that single bonds can rotate). As with the reactions from the previous sections, the regiochemical and stereochemical outcomes can be understood using the mechanisms – continue to resist memorizing the mechanism; rather, strive for understanding. That being said, you will need to learn/memorize reagents. The reagents in these sections are somewhat sophisticated; pay careful attention to the details, including the need to add reagents sequentially. There are two videos available through the WileyPLUS site and three videos available through the Khan Academy. Office Hours Video: Drawing the Mechanism of a Ionic Addition Reactions (5:18) – pairs with sections 9.3-9.5, 9.8 Essential Viewing – WileyPLUS Compares carbocation intermediates and three-membered ring intermediates. Office Hours Video: Stereoselectivity of Alkene Additions (9:38) – pairs with sections 9.5-9.10 Essential Viewing – WileyPLUS Discusses the stereochemical implications of syn and anti addition. Hydroboration-Oxidation (9:33) – pairs with section 9.6 Recommended Viewing – Khan Academy Generic description of the mechanism followed by examples. Halogenation (8:13) – pairs with section 9.8 Recommended Viewing – Khan Academy Generic description of the mechanism followed by examples. Halohydrin Formation (12:44) – pairs with section 9.8 Recommended Viewing – Khan Academy Generic description of the mechanism followed by examples....