Alkenes Structure and Preparation via Elimination Reactions

The main culprit is a small compound called ethylene (H2C CH2). At room temperature ethylene is a gas, and it functions as a growth hormone by tri ering the ripening process. In a well-ventilated area, a single fruit does not produce enough ethylene to affect nearby fruits significantly. But when fruit are placed in a bag, the concentration of ethylene builds up inside the ha, causing them to ripen more quickly. 

Many fruits are picked while still green, transported to stores, and then sprayed with ethylene gas to promote ripening. In some cases, their exposure to ethylene is insufficient, which explains why you might find green bananas in the grocery store. To ripen bananas in your home, simply place them in a paper bag, which subjects the bananas to their own natural ethylene. To speed up the process, place a ripe fruit in the bag as well, because ripe fruits produce more ethylene than unripe fruits. This method will work with any fruit that produces ethylene, including mangos, kiwis, avocados, tomatoes, apples, and pears. 

Like ethylene, many naturally occurring compounds contain a carbon-carbon double bond. This chapter will focus on the properties and synthesis of compounds that possess carbon-carbon double bonds. 

If necessary, review the suggested sections to prepare for this chapter. 

Rearrangements (Sections 6.8 - 6.11), Chair Conformations of Cyclohexane (Sections 4.11 - 4.13) 

Fill in the blanks below. To verily that your answers are correct, look in your textbook at the end of Chapter 8. Each of the sentences below appears in the section entitled Review of Concepts and Vocabulary. 

E2 reactions are said to be regioselective, because the more substituted alkene, called the product, is generally the major product. 

E2 reactions are stereospecific because they generally occur via the  

Substituted cyclohexanes only undergo E2 reactions from the chair conformation in which the 

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CHAPTER 8 Alkenes Structure and Preparation via Elimination Reactions... 

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