How Do Elimination Reactions Work

In this chapter, elimination reactions were presented both independently and in association with their related nucleophilic substitution mechanisms. Furthermore, the processes by which molecules undergo both El and E2 eliminations were presented and explained using bonding and nonbonding orbitals and their required relationships to one another. While much emphasis was placed on the planar relationships of orbitals required for both elimination reaction mechanisms, the special case of frans-periplanar geometries were described as necessary for efficient E2 eliminations to occur. 

E2 eliminations do not necessarily require acidic protons in order to proceed. Explain how this can occur. 

With an understanding of El mechanisms, one may realize that under SN l reaction conditions multiple products may form. In addition to the products predicted in Chapter 5 for the following molecules, predict plausible elimination products. 

Presently, several different organic reaction mechanisms have been presented. Keeping all of these in mind, predict all of the possible products of the following reactions and list the mechanistic type or types from which these products result. 

As mentioned earlier, stereochemistry is not of great concern in this book. However, certain mechanistic types will show specific stereochemical consequences when acting on chiral molecules. With this in mind, predict the product resulting from the E2 elimination of HBr when the shown isomer of 4-bromo-3-methyl-2-pentanone is treated with sodamide. Show all stereochemistry and explain your answer. 

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