EXP 15: Aniline

Indigo

The word “aniline” was derived from the Spanish word meaning ___.

Nitrobenzene (C6H5NO2)

The reduction of what compound makes aniline in large quantities?

Aniline (C6H5NH2)

What is the compound whose properties are determined in this experiment?

Colorless

When freshly prepared, what color is aniline?

Dark brown or red

Over time, what color does aniline become due to oxidation?

False; Analine is insoluble in water but soluble in organic solvents

True or False: Analine is soluble in water.

Basicity

What is the name of (Part 1)?

Distilled Water (di. H2O)

(Part 1) What is added to aniline (C6H5NH2)?

Anilinium Hydroxide (C6H5NH3OH)

(Part 1) What is the organic product formed from the reaction between aniline and distilled water?

Colorless

(Part 1) What is the color of the organic product formed from the reaction between aniline and distilled water?

No Change (Analine is a weak base)

(Part 1) What happens to the litmus paper when tested in the solution of aniline and distilled water?

True

True or False: A water suspension of aniline contains a sufficient concentration of OH- to precipitate slight by soluble metallic hydroxides.

Ferric Chloride (FeCl3)

(Part 1) What is added after the reaction between aniline and distilled water?

Anilinium Chloride (C6H5NH3Cl)

(Part 1) What is the organic product formed from the reaction between anilinium hydroxide and ferric chloride?

Reddish-Brown

(Part 1) What color is the organic product formed from the reaction between anilinium hydroxide and ferric chloride?

Salt Formation

What is the name of (Part 2)?

Salts

When with acids, what does aniline form?

Concentrated Hydrochloric Acid (Conc. HCl)

(Part 2) What is added to aniline?

Anilinium Chloride (C6H5NH3Cl)

(Part 2) What is the salt formed from the reaction between analine and hydrochloric acid?

Separation Layer (Upper: White Salt Ring of Anilinium Chloride Crystals, Bottom: Brown Solution)

(Part 2) What is observed after hydrochloric acid was added to analine?

Effect of NH2 Group on Substitution in the Benzene Ring

What is the name of (Part 3)?

Tri-substitution products

When halogens act upon aniline in water solution, what is formed?

Tribromoaniline

Bromine-water with aniline gives __.

Bromine Water (Br2 * H2O)

(Part 3) What is added to aniline?

Clear yellow solution and insoluble globules of bromine

(Part 3) What is the observed reaction of the solution of bromine water and aniline?

2,4,6-tribromoaniline (C6H2Br3NH2)

(Part 3) What is the organic product formed from the reaction between bromine water and aniline?

Diazotization

What is the name of (Part 4)?

Dissolving the amine in dilute aqueous acid and adding aqueous sodium nitrate

What is the process of converting the salt of an aromatic primary amine to the corresponding diazomium salt?

Concentrated Hydrochloric Acid (Conc HCl) & 5% Sodium Nitrite Solution (NaNO2)

(Part 4) What are the reagents added to aniline to create the diazomium salt?

Minimize decomposition of diazonium salt and nitrous acid

Why is the temperature kept low in (Part 4)?

Colorless

(Part D) What should the solution look like?

Benzenediazonium Chloride (C6H5ClN2)

(Part D) What is the diazomium salt formed?

Formation of Phenol

What is the name of (Part 5)?

Heated

(Part 5) What is done to the diazotized analine?

Phenol (C6H5OH)

(Part 5) What is the organic compound resulted from the heating of the diazotized aniline?

Glue/Paste-Like Odor

(Part 5) What is the odor resulted from heating the diazotized aniline?

Nitrogen Gas (N2)

(Part 5) What is the gas resulted from the heating of the diazotized aniline?

Reddish/Pinkish

(Part 5) What color does the solution turn after heating the diazotized aniline?

Coupling & Formation of Dyes

What is the name of (Part 7)?

Phenol (C6H5OH) & Resorcinol (C6H4(OH)2)

(Part 7) What are the two compounds that diazotized aniline is added to?

8 N Sodium Hydroxide (NaOH)

(Part 7) What is added as a catalyst?

Bright Yellow Precipitate; Yellow Solution

(Part 7) What is observed in the test tube with phenol and aniline (and sodium hydroxide)?

Bright Orange Precipitate; Orange Solution

(Part 7) What is observed in the test tube with resorcinol and aniline (and sodium hydroxide)?

p-hydroxyazobenzene (C12H10N2O)

(Part 7) What is the organic product formed between the diazotized aniline and phenol?

2,4-dihydroxyazobenzene (C12H10N2O2)

(Part 7) What is the organic product formed between the diazotized aniline and resorcinol?