Comparative Reactions of Amines Lab (PDF)

UST General Santos COMPARATIVE REACTION OF AMINES UST General Santos PRAYER BEFORE CLASS Holy Spirit, Divine Creator, true source of light and fountain of wisdom! Pour forth your brilliance upon my dense intellect...

UST General Santos COMPARATIVE REACTION OF AMINES UST General Santos PRAYER BEFORE CLASS Holy Spirit, Divine Creator, true source of light and fountain of wisdom! Pour forth your brilliance upon my dense intellect, dissipate the darkness which covers me, that of sin and of ignorance. Grant me a penetrating mind to understand, a retentive memory, method and ease of learning, the lucidity to comprehend, and abundant grace in expressing myself. Guide the beginning of my work, direct its progress and bring it to successful completion. This I ask through Jesus Christ, true God, and true man, living and reigning with You and the Father, forever and ever. Amen.  UST General Santos Learning Objectives: At the end of the Laboratory activity: The students should be able to distinguish primary, secondary, and tertiary amine using nitrous acid and Heinsberg tests.  UST General Santos Amines An ammonia derivatives of hydrocarbons. It be classified as either primary, secondary, or tertiary, depending on the number of carbon-containing groups that are attached to them.  UST General Santos Classification of Amines EXAMPLE  UST General Santos Aliphatic Amines Resistant to oxidation. Aliphatic (long Carbon-chain) primary and secondary amines are the most basic.  UST General Santos Aromatic Amines The amine of benzene called Aniline. It decreases the basicity of the amine. This effect can be either strengthened or offset depending on what substituents are the ring and on the nitrogen.  UST General Santos Properties of Amines Distinctive “Fishy” smell Basic class of organic compounds. Only Organic compound which are substantially basic in aqueous solution. Completely protonated by dilute solutions of strong acids.  UST General Santos Properties of Amines Lighter than water Soluble in water (1 to 5 carbon amines) Boiling point: Amine < Alcohol < Carboxylic Acid (with comparable masses) Hydrogen bonding significantly influences the properties of primary and secondary amines. Methyl and Ethyl amines are gases under standard conditions.  UST General Santos Test for the Presence of Amines 1. Nitrous Acid Test - (+) Result Nitrogen gas Primary Aliphatic Amines evolution Insoluble oil Secondary Aliphatic Amines produce Tertiary Aliphatic Amines Clear solution  UST General Santos Test for the Presence of Amines 2. Heinsberg Test - Distinguishes primary, secondary and tertiary amines.  UST General Santos LABORATORY ACTIVITY: COMPARATIVE REACTIONS OF AMINES  UST General Santos Nitrous Acid Test 1. Prepare 3 test tubes, each containing 2 mL of 6 M HCl. 2. Add 5 drops of the sample into a corresponding test tube. 3. Cool down the test tubes to approximately 0oC using ice bath. 4. Slowly add 2 mL of 10% NaN02 to each test tube. 5. Keep the mixtures of the ice bath for 5 mins., then warm to room temperature. 6. After reaching room temperature, allow the mixture to stand in the ice bath for 15 mins. 7. Record observation when applicable: effervescence, color of the gas evolved, formation and color of an oily layer, or appearance and color of precipitate.  UST General Santos Heinsberg Test 1. Place 5 drops of aniline to a test tube. 2. Add 5 mL of 10% NaOH and 10 drops of benzenesulfonyl chloride. 3. Cover the test tube with an appropriate stopper. Share the mixture vigorously for 5 mins. 4. Record any observation of changes to the color or the physical state of mixture. Use litmus paper to confirm alkalinity. 5. Cool the mixture to room temperature and add 6 M HCl until the mixture is acidic. 6. Record any observation of changes to the color or the physical state of the mixture. 7. Repeat the procedure for the other organic amines. N-methylamine and N,N-dimethylaniline