Anti-Markovnikov Additions to Triple Bonds

Solved Exercise 13-19 Working with the Concepts Using Alkynes in Synthesis 

Propose a synthetic scheme that will convert compound A into B (see margin). [Hint Consider 

The hint reveals to us a possible retro synthetic analysis of the problem  

Let us consider what we have learned so far in this chapter that can be helpful. This section has shown how alkynes can be converted to ketones by mercury ion-catalyzed hydration. Section 13-5 introduced a new strategy for the formation of carbon-carbon bonds through the use of alkynyl anions. Beginning with the three-carbon ketone A (acetone), our first task is to add a two-carbon alkynyl unit. Referring to Section 13-5, we can use any of several methods to convert ethyne into the corresponding anion. 

Finally, hydration of the terminal alkyne function, as illustrated for the cyclohexyl derivative shown on the previous page, completes the synthesis  

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Anti-Markovnikov Additions to Triple Bonds CHAPTER 13... 

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