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1、Chapter 14 Heterocyclic Compounds(杂环化合物),Heterocycle / Heterocyclic Compound 构成环系的原子除C外,还有其它杂原子。,O, S, N.,Hetero-atom (杂原子):,Heterocycle 杂环,Saturated Heterocycles 饱和杂环化合物,Aromatic Heterocycles 芳香杂环化合物,体现各自功能团的性质,一 .Classification & Nomenclature:,按环的大小,Five-membered ring,Six-membered ring,按杂原子的数目,一个杂
2、原子杂环,两个杂原子杂环,多个杂原子杂环,按环的拼合形式,单杂环(homo-heterocycle),稠杂环(fused-heterocycle),pyrrole 吡咯,thiophene 噻吩,furan 呋喃,Classification & Nomenclature,Five-membered ring heterocycles,imidazole 咪唑,pyrazole 吡唑,oxazole 口恶 唑,thiazole 噻唑,Isoxazole 异口恶 唑, Six-membered ring heterocycles,Classification & Nomenclature,pyr
3、idine 吡啶,pyrimidine 嘧啶,2H-pyran 2H- 吡喃,Pyridazine 哒嗪,Pyrazine 吡嗪,4H-pyran 4H- 吡喃, Fused-heterocycles,Classification & Nomenclature,quinoline 喹啉,iso-quinoline* 异 喹啉,Purine* 嘌呤,Indole 吲哚,蝶啶 pteridine,口丫啶 acridine,吩嗪 phenazine,carbazole 咔唑,Phenothiazine 吩噻嗪,Classification & Nomenclature,Attention!, “指示
4、氢” or “标氢”,最多的非累积双键外的饱和氢, 没有达到最多的非累积双键,“外加氢” 的标注,命名顺序:,-SO3H -COOH -COOR -CONH2 -CN -CHO -COR -OH -NH2 -R -NO2 -X,Classification & Nomenclature, 取代杂环的命名:,编号原则:单杂环、稠杂环;最小编号和优先顺序法则,iso-quinoline* 异 喹啉,Purine* 嘌呤,5-硝基-2-呋喃甲醛,4-氨基嘧啶,N,N-二乙基-3-吡啶甲酰胺,1,3,-二甲基嘌呤-2,6-二酮,3-甲基-5-氯喹啉,7-碘-8-羟基喹啉-5-磺酸,Classifica
5、tion & Nomenclature,Classification & Nomenclature, 互变异构的存在,编号及名称的改变,7H-嘌呤,9H-嘌呤,2,4-二羟基嘧啶,嘧啶-2,4-二酮,5-甲基吡唑,3-甲基吡唑,尿嘧啶(U),Classification & Nomenclature, 拼合杂环的命名:,非特定稠环,基本环,附加环,稠合边的表示,呋喃并2, 3-b 噻吩,吡咯并3, 2-b 噻吩,Classification & Nomenclature, 拼合杂环的命名:,整体稠环编号,取代基位置,6-苯基咪唑并2, 1-b噻唑,6H-吡唑并4, 5-d口恶 唑,二. Six
6、-membered Heterocyclic compounds,Pyridine 吡啶,1. Structure:,C5H5N,芳香性,较强的碱性,Kekules structure,Aromaticity ?,电子云的分布,E.S. 变难,N.S. 变易,Oxidation 难,Reduction 易,Basicity,Six-membered Heterocyclic compounds,2. Physical properties,(1) (偶极矩) Dipole moment, = 7.4110-38 c.m 3.90 10-38 c.m,I,C,方向一致,Six-membered
7、Heterocyclic compounds,(2) Solubility:,吡啶可以与水以任意比例互溶,3. Chemical reactions,a. Basicity of Pyridine,Basicity,Six-membered Heterocyclic compounds,Six-membered Heterocyclic compounds,Pyr.SO3,磺化试剂,酰化试剂,甲基化试剂,b. Electrophilic Substitution:,N 的-I,钝化环,反应条件剧烈,取代反应 发生在3-位(),Six-membered Heterocyclic compounds,Six-membered Heterocyclic compounds,不稳定,取代2-位,取代3-位,