Ch07- homework

1. Provide the major organic product in the reaction below.

1. Provide the structure of the major organic product(s) in the reaction below.

1. Provide the structure of the major organic product(s) in the reaction below.

2

CH

3

CH

2

C

M

CH

1. NaNH

2

. PhCH

2

Br

1. Complete the following tree of reactions by giving the major products. (don’t worry about g)

1. Draw an acceptable structure for 3- sec– butyl- 1- heptyne.

1. Provide the structure of the major organic product(s) in the reaction below.

Na, NH3

CH

3

CH

2

N

C

M

C

N

CH

3

1. Describe a sequence of reactions by which cis– 2- pentene could be prepared from acetylene.

1. Provide an acceptable name for the compound shown.

1. Provide the structure of the major organic product(s) in the reaction below.

1. Describe a sequence of reactions by which trans– 2- pentene can be prepared from propyne.

1. Provide the systematic name of the compound shown.

1. Draw an acceptable structure for 2- hexyne.

1. Provide the sequence of reagents that are needed to accomplish the multistep synthesis below.

1. Provide the major organic product in the reaction below.

1. Provide the structure of the major organic product of the following reaction.

1. Describe a sequence of reactions by which the aldehyde CH3CH2CH2CH2CHO could be prepared from acetylene.

1. Write structures and give IUPAC names for all alkynes with molecular formula C5H8.

1. Which hydrogens are more acidic, those of benzene or those of cyclohexane? Why?

1. Provide the structure of the major organic produt that results when 2- butyne is treated with 1 equivalent of HCl.

1. Provide the major organic product in the reaction below.

1. Why are terminal alkynes more acidic than other hydrocarbons?

1. Provide the major organic product in the reaction below.

1. Explain why HCMN is a stronger acid than HCMCH.

1. Give the reagents for the following reaction.

1. Provide the structure of the major organic produt that results when 2- butyne is treated with HgSO4/H2SO4 in water

1. Describe a sequence of reactions by which butylbenzene can be prepared from phenylacetylene.

1. Provide the structure of (2E,4E)- 2- chloro- 2,4- octadiene.

1. Provide the systematic name of the compound shown.

1. Provide the structure of the major organic product of the following reaction.

1. Provide the structure of the major organic product of the following reaction.

1. Provide the structure of the major organic product of the following reaction.

1. Name the following compound.

1. Provide the major organic product in the reaction below.

1. Provide the structure of the major organic product(s) in the reaction below.

1. Provide the structure of the major organic produt that results when 2- butyne is treated with H2 in the presence of Lindlar’s Catalyst.

1. Provide the major organic product in the reaction below.

1. Provide the major organic product of the following reaction sequence.

1. Provide the major organic product in the reaction below.

1. Provide the major organic product of the following reaction sequence.

1. Describe a sequence of reactions by which 3- heptyne can be straightforwardly prepared from acetylene.

1. Give the systematic name of the compound shown below.

1. Provide the major organic product in the reaction below.

1. Provide the structure of the major organic product of the following reaction.

1. Complete the following reaction.

Na, NH3

3

–

hexyne

1. Provide the sequence of reagents that are needed to accomplish the multistep synthesis below.

1)

2)

3) CH3CH2CMCCH2Ph

4)

5)

6)

1. 1) NaNH2
   1. CH3CH2Br
   2. NaNH2
   3. CH3Br
   4. H2, Lindlar’s catalyst
2. 7,7- dichloro- 5,5- dimethyl- 3- heptyne or 7,7- dichloro- 5,5- dimethylhept- 3- yne

9)

1. 1) NaNH2
   1. CH3CH2Br
   2. Na, NH3
2. 5,6,6- trimethyl- 1- heptyne 12)

13) 1. NaNH2

1. CH3CH2I
2. Na, NH3

14)

15)

18) Benzene. The carbon hybridization of benzene is sp2 while that of cyclohexane is sp3. The more s character in benzene causes its hydrogens to be more acidic than those of cyclohexane.

19)

20)

21) The carbanion which results upon deprotonation of a terminal alkyne has the lone pair of electrons in an sp hybrid orbital. The greater % s character of this orbital gives the orbital a significantly lower energy.

22)

1. Because nitrogen is more electronegative than carbon.
2. 1. NaNH2, 2. CH3CH2Br, 3. NaNH2, 4. CH3CH2Br, 5. 2 Br2 25)

26) 1) NaNH2

1. CH3CH2Br
2. H2, Pt

27)

28) (E)- 5- methyl- 5- hepten- 1- yne

29)

30)

31)

32) cis– 4,5- dimethyl- 4- hepten- 2- yne or (Z)- 4,5- dimethyl- 4- hepten- 2- yne

33)

34)

35)

36)

37)

38)

39)

1. 1) NaNH2
   1. CH3CH2Br
   2. NaNH2
   3. CH3CH2CH2Br
2. 1,7- dimethyl- 1,3- cycloheptadiene

42)

43)

1. trans– 3- hexene
2. 1. NaNH2
   1. CH3CH2I
   2. H2, Lindlar catalyst