第六章炔烃和共轭二烯 Conjug Dienes
第六章 炔烃和共轭二烯 Alkynes and Conjugated Dienes
Alkynes, also called acetylenes, are o hydrocarbons that contain a carbon carbon triple bond. acetylene itself, the simplest alkyne, was once widely used in industry as the starting material for the preparation of acetaldehyde, acetic acid, vinyl chloride, and other high- volume chemicals, but more efficient route using ethylene as starting material are now more common
Organic Chemistry Organic Chemistry Xiamen Xiamen University University Alkynes, also called acetylenes, are hydrocarbons that contain a carboncarbon triple bond. Acetylene itself, the simplest alkyne, was once widely used in industry as the starting material for the preparation of acetaldehyde, acetic acid, vinyl chloride, and other highvolume chemicals, but more efficient route using ethylene as starting material are now more common
6.1炔烃的结构、命名 和物理性质 Structure, Nomenclature, and g Physical Properties of Alkyne
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 6.1 炔烃的结构 命名 和物理性质 Structure, Nomenclature, and Physical Properties of Alkyne
61.1炔烃的结构 180° 106pm H—C≡三C—H 120pm 总_sp化,键角180,线形分子 2个π键,π电子云呈圆柱体 ■碳碳键长比烯键短
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 6.1.1 炔 烃的结构 H C C H 180 120pm 106pm sp杂化 键角180 º 线形分子 2 个 π 键 π电子云呈圆柱体 碳碳键长比烯键短
HH+C H
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 乙炔的 π电子云 H C C H H C C H
键长、键能比较 C-CC=CC≡C 键长154134120pm 键能347.3610.98368kJ/mol 已碳原子的电负性随杂化时S成分的增加而增大 3∠驴<sp C≡C-H有一定酸性pKa~25
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 键长 键能比较 C C C C C C 键长 154 134 120 pm 键能 347.3 610.9 836.8 k J / mol 碳原子的电负性随杂化时 S成分的增加而增大 sp 3< sp 2 < sp C C H 有一定酸性 pK a ~ 25
612炔烃的异构和命名 存在位置异构。 与烯烃的命名原则相同,改“烯”为“炔”。 (yne) 分子中同时存在烯键和炔键时,母体名 为“烯炔”(- enyne) 65432 CH2 CH, CHCHO≡ CCH, CH 6-Methyl-3-octyne 6-甲基-3-辛炔
Organic Chemistry Organic Chemistry Xiamen Xiamen University University 6.1.2 炔烃的异构和命名 存在位置异构 与烯烃的命名原则相同 改 “ 烯 ” 为 “ 炔 ” (-yne) 分子中同时存在烯键和炔键时 母体名 为 “烯炔 ” (-enyne) CH 3CH 2CHCH 2 C CCH 2CH 3 CH 3 8 7 6 5 4 3 2 1 6-Methy l-3-octyne 6-甲基-3 -辛炔
Nomenclature of Alkynes Alkynes follow the rules of hydrocarbon nomenclature already discussed. The suffix -yne is used in the base hydro- carbon name to denote an alkane and the position of the triple bond is indicated by its number in the chain Numbering always begins at the chain end nearer the triple bond so that the triple bond receives as low a number a as possible
Organic Chemistry Organic Chemistry Xiamen Xiamen University University Nomenclature of Alkynes Alkynes follow the rules of hydrocarbon nomenclature already discussed. The suffix –yne is used in the base hydrocarbon name to denote an alkane, and the position of the triple bond is indicated by its number in the chain. Numbering always begins at the chain end nearer the triple bond so that the triple bond receives as low a number as possible
g Compounds with more than one triple bond are called diynes, triyne, and so forth; compounds containing both double and triple bonds are called enynes(not ynenes) Numbering of an enyne chain always starts from the end near the first multiple bond whether double or triple
Organic Chemistry Organic Chemistry Xiamen Xiamen University University Compounds with more than one triple bond are called diynes, triyne, and so forth; compounds containing both double and triple bonds are called enynes(not ynenes). Numbering of an enyne chain always starts from the end near the first multiple bond, whether double or triple
a‖CH3C≡CCH2C三CCH2CH3 2. 5-Octadiyne 三 2.5-辛二炔 sopropylcyclodecyne 6-(1-甲基乙基)环癸炔 CH3CH=CHCH=CHC=CCH3 2, 4-Octadien-6-yne 24-辛二烯6-炔
Organic Chemistry Organic Chemistry Xiamen Xiamen University University CH 3C C C H 2 C CCH 2CH 3 2,5- O c t adiyn e 2, 5 - 辛 二 炔 2,4 -Oct adien- 6-yn e CH 3 C H CHCH CHC CCH 3 2,4 -辛二烯 - 6 - 炔 6-Isop r o p ylcy clodecyne 6-(1-甲基乙 基 )环癸 炔