Organic Chemistry, 6 th edition Paula Yurkanis Bruice Chapter 9 Elimination Reactions of Alkyl Halides Competition Between Substitution and Elimination Brian L. Groh Minnesota State University, Mankato Mankato, MN Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

Which alkyl halide will react most readily under E2 reaction conditions with sodium ethoxide? 9.2 Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

Which alkyl halide will react most readily under E2 reaction conditions with sodium ethoxide? 9.2 I - is the best leaving group and E has eight hydrogens that can readily be abstracted by a strong base. Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

In the following reaction, which base will most favor the anti-Zaitsev product? 9.2 Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

In the following reaction, which base will most favor the anti-Zaitsev product? 9.2 The most hindered base will favor anti-Zaitsev elimination. Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

Which of the following statements is false? An E2 reaction _________. 9.4 A.is a reaction in which the syn elimination pathway predominates B.is favored with high base concentration C.is favored with a good nucleophile D.is favored with a good leaving group E.is favored in a polar protic solvent Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

Which of the following statements is false? An E2 reaction _________. 9.4 In a bimolecular process the anti-elimination pathway predominates. A.is a reaction in which the syn elimination pathway predominates B.is favored with high base concentration C.is favored with a good nucleophile D.is favored with a good leaving group E.is favored in a polar protic solvent Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

Under E2 reaction conditions, which alkyl halide will most readily eliminate? 9.6 Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

Under E2 reaction conditions, which alkyl halide will most readily eliminate? 9.6 The predominant conformation of only D has the halide in the preferred axial position. Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

In the reaction of bromocyclohexane with sodium acetate using acetic acid as the solvent, which would be the expected reaction pathway? 9.8 Bruice: Organic Chemistry, © 2011 Pearson Education, Inc. A.Primarily substitution B.Only elimination C.Both substitution and elimination D.Primarily addition E.No reaction

In the reaction of bromocyclohexane with sodium acetate using acetic acid as the solvent, which would be the expected reaction pathway? 9.8 Bruice: Organic Chemistry, © 2011 Pearson Education, Inc. A.Primarily substitution B.Only elimination C.Both substitution and elimination D.Primarily addition E.No reaction With a good leaving group, weak nucleophile, and a polar solvent, substitution will be the major pathway.

Which set(s) of reagents will give cyclohexyl ethyl ether in high yield? 9.9 Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.

Which set(s) of reagents will give cyclohexyl ethyl ether in high yield? 9.9 A will eliminate while C will give a mixture of ethers. Bruice: Organic Chemistry, © 2011 Pearson Education, Inc.