6.2炔烃的化学性质 Chemical Properties of Alkynes
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 6.2 炔烃的化学性质 Chemical Properties of Alkynes
621炔烃的酸性 ■末端炔烃酸性比水、醇弱,但比氨强 CH3CH3 CH2-CH2 NH3 CH=CH EtOH H2O K。50 pl 40 35 25 1615.7
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 6.2.1 炔烃的酸 性 末端炔烃酸性比水 醇弱 但比氨强 CH 3 C H 3 CH 2 C H 2 N H 3 CH C H Et OH H 2 O pK a 50 40 3 5 25 1 6 15.7
40 2Na+NH3(i一→2NaNH2+H2 NH3o CH=CH +NaNH,33 CH=CNa NaC≡CNa CH=CH+AgNH3)→AgC=CAg白 eCH=CH+CuNH)→CC=CC山红 RC≡CH+HOBr RC≡CBr+HO
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 2N a + NH 3(liq. ) 2N aNH2 + H2 - 40 CH C H + N aNH2 NH 3(l ) - 33 CH CNa NaNH2 NaC CNa C H C H + Ag (NH 3 ) + AgC CAg 白 C H C H + Cu(NH 3 ) + CuC CCu 红 RC C H + H OBr RC CBr + H2 O
应用 合成 CH, CHoCHBr CH≡CNa CH=≡CCH2CH2CH NanH CH2C≡ CCH,CH2CH (2)CH3 I 鉴别
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 应 用 合成 CH CNa CH 3CH 2CH 2Br CH CCH 2CH 2CH 3 (1) N aN H 2 CH 3C C C H 2CH 2CH 3 (2) C H 3 I 鉴别鉴别
622末端炔烃与醛酮的加成 CHo-O CH≡CH+KOH CH≡C HoO CH≡C-CHO CH≡C-CH2OH KOH 谷CH≡CH+CH3C-CH OH CH3-C-C≡CH CH
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 6.2.2 末端炔 烃与醛酮的加成 CH CH + KO H CH C CH 2 O CH C C H 2 O H 2 O CH C C H 2OH CH CH + CH 3 C C H 3 O KOH CH 3 C CH 3 OH C C H
523炔烃的亲电加成 1加卤素 E. CH2-CHCH2C=CH Br2(1 mol)- BrCH-CHCH2C≡CH Br 烯键比炔键容易加成 2 CH≡CH C-C Fecl H△ 或SnCl2 ClCH-CHCl2 反式加成
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 5.2.3 炔 烃 的亲电加成 1. 加卤素 烯键比炔键 容易加成 CH 2 CH C H 2 C CH + Br 2(1 mo l ) BrCH 2 CHCH 2 C CH B r 反式加成 CH CH 或 SnCl 2 C C Cl H H Cl Cl 2CH CHCl 2 Cl 2 FeCl 3 Cl 2
2加卤化氢 C HCI RC≡CH RC=CH HCI -Rc-CH HgC gcl2 Cl C H Cl Cl RC-CH →RC=CH2 RC-CH rp More stable C RCHECH ess stable 符合马氏规则
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 2.加卤化氢 RC CH HCl HgCl 2 RC CH 2 Cl RC CH 3 Cl Cl HCl H + Cl H + RC CH 2 RCH C H Less stable More stable Cl RC CH 3 Cl RC CH 2 Cl 符合马氏规则
三3加水 Heso ID CH=CH H,O CH=CH HoSO O OH CH3-c-h HgSO4 RC=CH 3RC≡CH+H2O HoSO OH R一C—CH
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 3.加水 Hg S O 4 CH CH + H 2 O H 2SO 4 CH CH 2 OH CH 3 C O H RC CH + H 2 O Hg S O 4 H 2SO 4 RC CH 2 OH R C O CH 3
HgSO4 RC=CHR' RC≡CR+H2O H2SO4 OH RCHECR OH R-CCH2R+ rch,-c-R
Organic Chemistry Organic Chemistry Xiamen Xiamen University University RC CR' + H 2 O Hg S O 4 H 2SO 4 RC CHR' OH R C O CH 2R' RCH CR' OH RCH 2 C O + R
回624炔烃的硼氢化一氧化反应 (1)B2H6 R、 H 互变异构 GRC≡CH C=C RCH, CHO (2)H2O2,OH H OH 1) B,H RC≡CR 2)H2O2, OH RC-CH2R RCH2--CR' g末端炔烃经硼氢化—氧化反应生成醛, 其它炔烃则生成酮。 ⑨D
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 6.2.4 炔烃的硼 氢 化 —氧化反应 RC C R' RC C H 2R' O RC H 2 CR' O + RC C H (1) B 2 H 6 (2) H 2 O 2, OH − C C H H R OH 互变异构 RCH 2CH O (1) B 2 H 6 (2) H 2 O 2, OH − 末端炔 烃经硼氢化 —氧化反应生成醛 其它炔 烃则生成酮