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大学-二烯烃和共轭体系习题加答案

大学-二烯烃和共轭体系习题加答案
大学-二烯烃和共轭体系习题加答案

大学-二烯烃和共轭体系习题

(一) 用系统命名法命名下列化合物:

(1)

(2)

4-甲基-1,3-戊二烯

2-甲基-2,3-戊二烯

(3)

(4)

2-甲基-1,3,5-己三烯 (3Z)-1,3-戊二烯

(二) 下列化合物有无顺反异构现象:若有,写出其顺反异构体并用Z,E-命名法命名。

解:(1) 无;

(2) 有;(3E)-1,3-戊二烯, (3Z)-1,3-戊二烯;

(3) 有;(3Z,5Z)-3,5-辛二烯, (3Z,5E) -3,5-辛二烯,(3E,5E) -3,5-辛二烯; (4) 有;(3E)-1,3,5-己三烯, (3Z)-1,3,5-己三烯; (5) 无 (三) 完成下列反应式:

解:红色括号中为各小题所要求填充的内容。

(1)

(2)

(3)

(4)

CH 2=CHCH=C(CH 3)2CH 3CH=C=C(CH 3)2CH 2=CHCH=CHC=CH 3

CH 3

C=C

CH=CH 2

CH 3

H H

(1)2-甲基-1,3-丁二烯(2)1,3-戊二烯(3)3,5-辛二烯(4)1,3,5-己三烯(5)2,3-戊二烯+ HOOCCH=CHCOOH

CH

CH +

3

3

H

+COOCH 3COOCH 3H

H

3

3

H

H

+

H

COOCH 3H

CH 3OOC

(5)

(6)

(7)

(8)

(9)

(10)

(四) 给出下列化合物或离子的极限结构式,并指出哪个贡献最大?

(2) (3)

(4)

(5)

(6)

解: (1)

贡献最大(非电荷分离)

(2)

结构相似,二者贡献一样大

(3)

结构相似,二者贡献一样大

+ RMgX MgX

+ RH

+

3

CHO

+

CH 2Cl

+

CH 2Cl KMnO +

HOOCCH 2CHCH 2CH 2COOH

CH 2Cl

(A)(B)

CH 3

3

3

3

CH

CH 33

CH 3

H CH 3CH 3

CH 3

(1)CH

3C

N (CH 3)2C=CH C(CH 3)2CH 2=CH CH 2CH 2

C CH 3

CH 3

C CH=CH 2CH 3C

N

CH 3C

N

CH 3C

N (CH 3)2C=CH C(CH 3)2

(CH 3)2C CH=C(CH 3)2CH 2=CH CH 2

CH 2

CH=CH 2

(4)

各共振结构式结构相似,能量相同,对真实结构的贡献相同。

(5)

贡献最大(与电负性预计相同)

(6)

贡献最大(共价键最多)

(五) 化合物和同相比,前者C=C 双键的电子云密度降低,而后者C=C 双键的电子云密度升高。试用共振论解之。

解:的真实结构可用共振论表示如下:

其中(II)对真实结构的贡献就是使C=C 双键带部分正电荷,电子云密度降低。

的真实结构可用共振论表示如下:

其中(II)对真实结构的贡献就是使C=C 双键带部分负电荷,电子云密度升高。

(六) 解释下列反应:

(1)

(2)

解:

(1)

... ...CH 2

C CH 3O

CH 2C CH 3

O -

CH 3C CH 2CH 3

C CH CH 2O

CH 3C CH CH 2O

CH 3

C CH CH 2

O

CH 2=CH NO 2CH 2=CH OCH 3CH 2=CH 2CH 2=CH

NO 2CH 2=CH N

O

-

O

CH 2

CH=N O -O

-

(I)

(II)

CH 2=CH OCH 3

2

3

CH 2

CH=OCH 3(I)

(II)

Br

Br Br

+ 2 Br 2

CH 2

CH 2Br

NBS CCl 4 ,

Br

Br Br

Br Br

Br

Br 1,4-加成

1,6-加成

(2)

… …

(七) 某二烯烃与一分子溴反应生成2,5-二溴-3-己烯,该二烯烃若经臭氧化再还原分解则生成两分子乙醛和一分子乙二醛 (O=CH-CH=O)。试写出该二烯烃的构造式及各步反应式。 解:该二烯烃的构造式为: 2,4-己二烯

各步反应式略。

(八) 3-甲基-1,3-丁二烯与一分子氯化氢加成,只生成3-甲基-3-氯-1-丁烯和3-甲基-1-氯-2-丁烯,而没有2-甲基-3-氯-1-丁烯和3-甲基-1-氯-2-丁烯。试简单解释之,并写出可能的反应机理。

解:由于C +

稳定性:

所以,只有与

相关的产物生成:

NBS

少量Br 2,Br 2

2 Br CH 2

+ Br

CH 2

2

+ Br 2

+ Br CH 2Br

2

CH 3CH=CH CH=CH CH 3

CH 2CH

CH 3CH 3

CH

3

CH=CH 2

CH 3CH 3

CH=CH 2CH 3

CH 2CH=CH 2

CH 3

CH 3

CH=CH 2

CH 3

H +

CH 3

C CH=CH 2

CH 3

Cl

CH 3

CH

CH 3

CH 2

+

Cl -

Cl -

CH 3

CH CH 32

Cl

(九) 分子式为C 7H 10的某开链烃(A),可发生下列反应:(A)经催化加氢可生成3-乙基戊烷;(A)与硝酸银氨溶液反应可产生白色沉淀;(A)在Pd/BaSO 4催化下吸收1 mol H 2生成化合物(B), (B)能与顺丁烯二酸酐反应生成化合物(C)。 试写出(A)、(B)、(C)的构造式。

解:

(十) 下列各组化合物分别与HBr 进行亲电加成反应,哪个更容易?试按反应活性大小排列顺序。

, , ,

1,3-丁二烯, 2-丁烯, 2-丁炔 解:(1) 反应活性顺序:

>>

(考虑C +稳定性!)

(2) 反应活性顺序为:1,3-丁二烯 > 2-丁烯 > 2-丁炔 (考虑C +稳定性!) (十一) 下列两组化合物分别与1,3-丁二烯[(1)组]或顺丁烯二酸酐[(2)组]进行Diels-Alder 反应,试将其按反应活性由大到小排列成序。

(A) (B)

(C)

(A)

(B)

(C)

解:反应活性:(1) B >C >A ;

(2) A >B >C (C 难以形成s-顺式构型,不反应) (十二) 试用简单的化学方法鉴别下列各组化合物: (1) 己烷, 1-己烯, 1-己炔, 2,4-己二烯

(2) 庚烷, 1-庚炔, 1,3-庚二烯, 1,5-庚二烯

C CH 3

CH 2CH 3

CH

CH=C CH CH 3

CH 2CH 3

CH 2

O

O (A)

(B)

(C)

(1)CH 3CH=CHCH 3CH 2=CH CH=CH 2 CH 3CH=CH CH=CH 2 CH 2=C

2 CH 3CH 3

(2)CH 22 CH 3CH 3

CH 3CH=CH CH=CH 2 CH 2=CH CH=CH 2

CH 3CH=CHCH 3(1)CH 3

CN

CH 2Cl

(2)CH 2=C CH=CH 2

CH 3

CH 2=CH CH=CH 2 CH 2=C C=CH 2

3)3

(CH 3)3

解: (1)

(2)

(十三) 选用适当原料,通过Diels-Alder 反应合成下列化合物。

(3)

(4)

(5)

(6)

解:(1)

(2)

(3)

(4)

CH 3(CH 2)4CH 3CH 2=CH(CH 2)3CH 3CH C(CH 2)3CH 3CH

3CH=CHCH=CHCH 3

323

24裉色x

灰白色沉淀

白色沉淀

x

或KMnO 4

裉色裉色

CH 3(CH 2

)5CH 3CH 2=CHCH=CH(CH 2)2CH 3CH C(CH 2)4CH

3

x

灰白色沉淀

x x

或KMnO 4

24CH 2=CH(CH 2)CH=CHCH 3

裉色裉色

323

(1)CH 2Cl (2)C O O

O

CH 3

CH 3

C CH 3

O

2Cl

C O O

O

CH 2

Cl CH 2Cl +

C O O

C O

O

O

+ O 2

V 2O 5

?

+

CH 3CH 3C CH

3?

2

Cl

CH 2Cl

+

2Cl Cl

(5)

(6)

(十四) 三个化合物(A)、(B)和(C),其分子式均为C 5H 8,都可以使溴的四氯化碳溶液褪色,在催化下加氢都得到戊烷。(A)与氯化亚铜碱性氨溶液作用生成棕红色沉淀,(B)和(C)则不反应。(C)可以顺丁烯二酸酐反应生成固体沉淀物,(A)和(B)则不能。试写出(A)、(B)和(C)可能的构造式。

解:(A)

(B) or

(C)

(十五) 1,2-丁二烯聚合时,除生成高分子聚合物外,还有一种二聚体生成。该二聚体可以发生如下的反应: (1) 还原后可以生成乙基环己烷; (2) 溴化时可以加上两分子溴;

(3) 氧化时可以生成β-羧基己二酸

根据以上事实,试推测该二聚体的构造式,并写出各步反应式。

解:该二聚体的构造式为:

各步反应式略。

C O C O

C O

C O

+

+CN

CN H

H

CH 3CH 2CH 2C CH CH 3C CCH 2CH 3CH 2=CHCH 2CH=CH

2CH 2=CHCH=CHCH 3HOOCCH 2CHCH 2CH 2COOH COOH

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