178 CHAPTER 4 Reactions of Alkenes
Problems
- Give the major product of each of the following reactions:
- Identify the electrophile and the nucleophile in each of the following reaction steps. Then draw curved arrows to illustrate the
bond-making and bond-breaking processes. - What will be the major product of the reaction of 2-methyl-2-butene with each of the following reagents?
a. HBr h. followed by
b. i.
c. HI j.
d. k.
e. ICl l.
f. m. followed by
g. n. followed by- Which of the following compounds is the most stable?
3,4-dimethyl-2-hexene; 2,3-dimethyl-2-hexene; 4,5-dimethyl-2-hexeneWhich would you expect to have the largest heat of hydrogenation? Which would you expect to have the lowest heat of
hydrogenation?- When 3-methyl-1-butene reacts with HBr, two alkyl halides are formed: 2-bromo-3-methylbutane and 2-bromo-2-methylbutane.
Propose a mechanism that explains the formation of these products. - Problem 30 in Chapter 3 asked you to give the structures of all alkenes with molecular formula Use those structures to
answer the following questions:
a. Which of the compounds is the most stable? b. Which of the compounds is the least stable?
C 6 H 12.Br 2 +excess NaCl Hg(O 2 CCF 3 ) 2 +CH 3 OH, NaBH 4H 2 >Pd BH 3 >THF, H 2 O 2 >HO-Br 2 >CH 3 OHHI+peroxide Br 2 >H 2 OBr 2 >CH 2 Cl 2HBr+peroxide H 2 O+trace HClHg(OAc) 2 , H 2 O NaBH 4a.b. CH 3 CH CH 2++c. CH 3 C+CH 3CH 3+CH 3 CHCH 3CH 3 OHBrCl–CH 3 C +OCH 3CH 3CH 3 HCH 3 CHCH 2 BrCH 3 CHCH 3Cl+CHa.CH 2 CH 3b. CH 2 CCH 2 CH 3+ HBr+ HBrCH 3c.CH 2d. CH 3 CH 2 CCH + HBrCH 3CH 2CH 3+ HBr