CH3 POCl3 pyridine CH2 OH H20 CH3 H3C CH3 Secondary alcohols are often dehydrated in an E2 reaction to give an alkene. Elimination follows Zaitsev's rule to give the more substituted alkene as the major product. Since the reaction occurs via an E2 mechanism, there is no risk of rearrangement of the carbon skeleton as could possibly occur if the elimination occurred via an E1 mechanism with a carbocation intermediate Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions Il CI CH3 HO +CI Cl H3C CH3 Нас CH3 Cl Retry Entire Group 8 more group attempts remaining Submit Answer

Rearrangements can occur during the dehydration of 1° alcohols even though no 1° carbocation is formed—that is, a 1,2-shift occurs as the C − OH2+ bond is broken, forming a more stable 2° or 3° carbocation, as shown. Using this information, draw a stepwise mechanism that shows how CH3CH2CH2CH2OH is dehydrated with H2SO4 to form a mixture of CH3CH2CH = CH2 and the cis and trans isomers of CH3CH = CHCH3. We will see another example of this type of rearrangement in Section 18.5C.

Draw the organic product of the following reaction. CH3 CH3C=CHCH3 meta-Chloroperoxy- benzoic acid

4) One of the diastereomeric cyclohexyl bromide starting materials below will readily undergo an E2 reaction while the other one will not. Fill in the requested information in boxes and lines indicated including the structure of the alkene product that does undergo an E2 reaction (use scratch paper first please). draw the expected major alkene product draw lowest E chair conformations Me. Ме Me EtO: Na Me "Ме :Br: Ме. Ме Me Me" Ме EtO: Na :Br: Required arrangement of H and LG (Br) for E2? (no acronyms). What is the rate law for and E2? On the template at left, draw all o & o* orbitals involved in the allowed E2 process.

The deuterated ethanol shown can be converted to an alkyl halide via a mesylate intermediate. Complete the mechanism, draw the final product (with nonbonding electrons) and select the correct absolute stereochemistry of the starting material and the final product.

Complete the following nucleophilic substitution reactions. In each reaction, show all electron pairs on both the nucleophile and the leaving group.