VJC 2025 Organic Compounds Notes

1 VICTORIA JUNIOR COLLEGE CHEMISTRY DEPARTMENT Tan Kuang Shing (tan.kuang.shing@vjc.edu.sg) ORGANIC NITROGEN COMPOUNDS [H2 only] SLS Lessons 1 2 3 Topics Amines Amides Amino Acids & Proteins Pages 1 - 14 15 - 23 24 – 31 Tutorial Q 1 2 – 6 7 – 9 LESSON OUTLINE PART I: AMINES 1 Classes of Amines 2 Nomenclature of Amines 3 Properties of Aliphatic Amines 4 Properties of Phenylamine 5 Basicity of Amines 6 Preparation of Aliphatic Amines 6 .1 Nucleophilic Substitution of Halogenoalkanes 6 .2 Reduction of Amides 6.3 Reduction of Nitriles 7 Preparation of Phenylamine by Reduction of Nitrobenzene 8 Reactions of Aliphatic Amines and Phenylamine 8 .1 Neutralisation 8 .2 Nucleophilic Substitution of Halogenoalkanes 8 .3 Condensation Reaction with Acyl Chloride 9 Electrophilic Substitution of Phenylamine PART II: AMIDES 1. Classes of Amides 2. Nomenclature of Amides 3. Properties of Amides 4. Preparation of Amides by Condensation Reaction between Amines and Acyl Chlorides 5. Reactions of Amides 5 .1 Acid Hydrolysis 5 .2 Base Hydrolysis 5 .3 Reduction PART III: AMINO ACIDS AND PROTEINS 1. Structure and Nomenclature 2. Classification of Amino Acids 3. Acid-Base Nature of Amino Acids 3.1. Formation of Zwitterions and their Physical Properties 3.2. Acid-Base Properties 3.2.1 Titration Curve of a Fully Protonated Neutral Amino Acid, Glycine H 3N+CH2CO2H 3.2.2 Titration Curve of a Fully Protonated Acidic Amino Acid, Glutamic Acid H3N+CH(CH2CH2CO2H)CO2H 3.2.3 Titration Curve of a Fully Protonated Basic Amino Acid, Lysine H3N+CH(CH2(CH2)3NH3+)CO2H 4. Peptide (Amide) Bonds Formation 4.1 Condensation Reaction between Amino Acids 4.2 Properties of a Peptide (Amide) Bond 5. Formation of Proteins 6. Hydrolysis of Proteins 6.1 Acid-Base Catalysed Hydrolysis 6.2 Enzymatic Hydrolysis

2 ASSESSMENT OBJECTIVES (a) D escribe the formation of amines as exemplified by ethylamine (through amide and nitrile reduction) and by phenylamine (through the reduction of nitrobenzene) (b) Describe the reaction of amines in the formation of salts (c) Describe and explain the basicity of primary, secondary and tertiary amines in the gaseous phase (interpret as Lewis bases) (d) E xplain the relative basicities of ammonia, ethylamine and phenylamine in aqueous medium, in terms of their structures (e) Describe the reaction of phenylamine with aqueous bromine (f) D escribe the formation of amides from the condensation reaction between RNH 2 and R'COCl (g) Explain why an amide is neutral in terms of delocalisation of the lone pair of electrons on nitrogen (h) Describe the chemistry of amides, exemplified by the following reactions: (i) h ydrolysis on treatment with aqueous alkali or acid (ii) reduction to amines with lithium aluminium hydride (i) Describe the acid/base properties of amino acids and the formation of zwitterions (j) Describe the