Organic chemistry Nitrogenous Compounds Organic chemistry 12 1

有机化学 Organic chemistry 第十二章 含氮化合物 Nitrogenous Compounds 材料与化学 程学院

有机化学 Organic chemistry 12. 1 Nitro Compounds R-NO 2 Functional group： -NO 2 12. 1. 1 Structure、Classification and Nomenclature 1. Classification (1)根据碳架分类： (2)根据硝基相连的碳分类： 材料与化学 程学院

有机化学 Organic chemistry Aromatic nitro-compounds: nitro group π-π，p-π共轭； -NO 2 有 -I, -C 效应 材料与化学 程学院

有机化学 Organic chemistry 3. Nomenclature Nitro is as substitutional group. 2 -nitro butane 2–nitronaphthalene 2–methyl– 5–isopropylnitrobenzene 材料与化学 程学院

有机化学 Organic chemistry 12. 1. 2 Aliphatic Nitro Compounds Nitration of alkane-as mixture solvent IR: N-O伸缩振动: 1500~1550 cm-1 1290~1360 cm-1 材料与化学 程学院

有机化学 Organic chemistry Chemical properties Acidity of -H 含有 -H的伯或仲硝基化合物能逐渐 溶解于氢氧化钠(生成稳定的负离子): CH 3 NO 2 CH 3 CH 2 NO 2 CH 3 CH CH 3 NO 2 p. Ka 10. 2 8. 5 7. 8 材料与化学 程学院

有机化学 Organic chemistry 12. 1. 3 Aromatic Nitro-Compounds IR: 1540 cm-1， 15411350 cm-1 870 cm-1 材料与化学 程学院

有机化学 Organic chemistry 12. 2 Amines 氨分子的H原子部分或全部被烃基取代 12. 1. 1 Structure、Classification and Nomenclature 1. Classification 材料与化学 程学院

有机化学 Organic chemistry 12. 2. 3 Chemical properties of amines N原子上的孤对电子 + H X 碱性(basicity): 亲核性(nucleophilicity): + 材料与化学 程学院

有机化学 Organic chemistry 1. 碱性(basicity): Amines p. Kb NH 3 4. 7 CH 3 NH 2 3. 4 (CH 3)2 NH (CH 3)3 N 3. 3 4. 3 9. 4 13 8. 7 材料与化学 程学院

有机化学 Organic chemistry 2. Alkylation of amines and thermal reaction of quaternary ammonium base. Formation of quaternary ammonium salts 材料与化学 程学院

有机化学 Organic chemistry The formation of quaternary ammonium base： β-H heat β- Elimination to form alkenes and an amine 材料与化学 程学院

C 2–C 3 有机化学 Organic chemistry C 1–C 2 Hofmann rule is opposed to the Zaitsev rule, To give a less substituted alkene. The Hofmann Elimination 材料与化学 程学院

3. Acylation of amines 有机化学 Organic chemistry Acylating agents: acyl chlorides, carboxylic acid anhydrides Synthesis of Paracetamol （扑热息痛）: 芳胺易氧化（如硝化反应等）。氨基 在反应时需保护。 材料与化学 程学院

有机化学 Organic chemistry Decreasing the activity of aryl ring or Protecting amino groups : 材料与化学 程学院

5. Reactions of amines with nitrous acid (Nitrosation ) (A) Reactions of primary aliphatic amines with nitrous acid Nitrosating agent: 有机化学 Organic chemistry Primary aliphatic amines Nitrous acid to yield unstable aliphatic diazonium salt. Alkene, alcohol, alkyl halide材料与化学 程学院

有机化学 Organic chemistry (B) Reactions of primary arylamines with nitrous acid Aryl diazoniumsalts are stable below 5℃ (C) Reactions of secondary amines with nitrous acid both aryl amines and alkyl amines react with nitrous acid to yield N-nitrosoamines 材料与化学 程学院

有机化学 Organic chemistry (D) Reactions of tertiary amines with nitrous acid Tertiary aryl amines react with nitrous acid to form C-nitroso aromatic compounds: 6. Electrophilic substitution reaction of aromatic amines 材料与化学 程学院

有机化学 Organic chemistry 12. 2. 4 Preparation of amines 1. Preparation of amines by reduction Reduction of nitriles to amines Reduction of nitro compounds to arylamines 材料与化学 程学院

Reduction of amides to amines: 有机化学 Organic chemistry Reductive amination: Imine 材料与化学 程学院

2. Hofmann rearragement 有机化学 Organic chemistry 3. The Gabriel synthesis of primary amines Primary alkyl halide, SN 2 Reagent: Potassium salt of Phthalimide （邻苯二甲酰胺钾盐） 材料与化学 程学院

有机化学 Organic chemistry 4. Preparation of amines by alkylation of ammonia 12. 3 The nature of the diazonium salt and its application in the synthesis 偶氮二异丁腈(AIBN) 材料与化学 程学院

有机化学 Organic chemistry 12. 3. 1 Substitution reaction The diazonium group may be replaced by other atomes or groups: －X, －OH, －CN and －H. Aryl diazonium salts can be prepared from arene: A: Replacement of the diazonium group by -OH Aryl diazonium ion is converted to phenols 材料与化学 程学院

Hydrolysis 有机化学 Organic chemistry : Electron-withdrawing group Question: Design a synsthesis of B: Replacement of the diazonium group by -H, deamination Aryl diazonium salts react with hypophosphorous acid (H 3 PO 2) or ethanol to yield the product: 材料与化学 程学院

有机化学 Organic chemistry Deamination 脱氨基作用 材料与化学 程学院

有机化学 Organic chemistry C: Replacement of the diazonium group by -X, －CN The Sandmeyer reaction: Aryl diazonium salts react with cuprous chloride, cuprous bromide, cuprous cyanide (70% overall) 材料与化学 程学院

有机化学 Organic chemistry (65% overall) The preparation of aryl iodides The preparation of aryl fluorides: (69%) 材料与化学 程学院

有机化学 Organic chemistry The value of diazonium salts in synthesis: 1. Substituents that are otherwise accessible only with difficulty, such as －F, －I, －CN, －OH, may be introduced onto a benzene ring. 2. Compounds that have substitution patterns 3. not directly available by electrophilic 4. aromatic substitution can be prepared Aniline 2, 4, 6 -Tribromoaniline (100%) 1, 3, 5 -Tribromo. Benzene(74 -77%) 材料与化学 程学院

有机化学 Organic chemistry 12. 3. 2 Azo coupling Aryl diazonium salts are weak electrophiles, they react with highly reactive aromatic compounds, to yield azo compounds 对二甲氨基偶氮苯 Azo dyes （偶氮染料） 甲基橙 材料与化学 程学院

有机化学 Organic chemistry 萘系化合物 12. 4 Azo compounds and azo dyes 材料与化学 程学院

有机化学 Organic chemistry 12. 5 Diazomethane and the carbene 12. 6 Azide compounds and uramine RN 3 azide uramine 材料与化学 程学院

有机化学 Organic chemistry 12. 7 Nitrile, isonitrile and derivatives HCN分子中氢原子被取代后的化合物 一个σ键 两个π键 氰基(cyano-) Nomenclature 丁腈 乙腈 (ethanenitrile) (butanenitrile) 苯甲腈(苄腈) (benzonitrile) 材料与化学 程学院

有机化学 Organic chemistry Reactions 1. Hydrolysis 2. Reaction with organometallic reagents 材料与化学 程学院

有机化学 Organic chemistry 3. Reduction isonitrile Isocyanate Isothiocyanate 12. 8 Surfactant 材料与化学 程学院