tb7 - Chal!.ter7 - Alkenes: Reactions and Svnthesis To...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chal!. .ter7 - Alkenes: Reactions and Svnthesis To answer the questions below consider the following reaction: When cyclohexene reacts with chlorine in carbon tetrachloride the trans-dihalide is fonned. 0 ~ CC4 (X CI ". Cl 1. Write the complete stepwise mechanism for this reaction. Be sure to show all intennediate structures and all electron flow using arrows. Answer: H O ALt -- C?~Cj~ . H (X CI "'CI 2. Since the two chlorine atoms add to opposite faces of the cyclohexene double bond, we say that the reaction occurs with: a. b. c. d. syn stereochemistry cis stereochemistry anti stereochemistry retention of stereochemistry Answer: c 3. The observed stereochemistry of addition of chlorine to cyclohexene is explained by the intennediacy of a: a. b. c. d. cyclonium ion carbocation carbene chloronium ion Answer: d 4. Provide the IUPAC name for the product of the reaction of cyclohexene with chlorine. Answer: trans-l ,2-dichlorocyclohex~e 5. Draw both chair confonnations of trans-l ,2-dichlorocyclohexane on the templates provided below. Circle the least stable confonnation. c:::;J - ~ - 48 Chapter 7: Alkenes: Reactions and Synthesis
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Answer: - ~a CI ~ Consider the reaction sequence below to answer the following questions: (J' ~ OH HgOAc Hg(OAch, H20/TH~ ?" I NaB~. ~ + HOAc cf+ Hg 6. Write the complete reaction mechanism for the first step of this reaction sequence. Show all electron flow with arrows and show all intermediate structures. Answer: () ~f\ ?AC I " \Hg-OAC ~ U ~HgOAC (). + HOAc I H r'lHf'e 4-""'"6: OAc ~HgOAC ~ '" @/OAc ~ () r (H + H2O: e OAc . 7. The intermediate in the first step of this reaction sequence is called a: a. carbocation c. mercurinium ion d. mercapto species. b. cyclonium ion Answer: c 8. In the second step of this reaction sequence, the organomercury compound is treated with sodium borohydride, NaBH4, to yield the alcohol product. This replacement of a carbon-mercury bond with a carbon-hydrogen bond is termed: a. an oxidation b. a reduction c. a hydroxylation d. a cycloaddition Answer: b
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 11

tb7 - Chal!.ter7 - Alkenes: Reactions and Svnthesis To...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online