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Chemistry 7B

IDENTIFICATION OF ORGANIC COMPOUNDS

I. Preliminary Examination A. Physical State B. Crystalline Form C. Color D. Odor E. Ignition Test

II. Physical Constants and Purity A. Melting Point B. Boiling Point C. Refractive Index D. Density E. Freezing Point F. Purification (if necessary)

III. Tests A. Water (check pH) B. 5% Hydrochloric Acid C. 5% Sodium Hydroxide D. 5% sodium bicarbonate E. Concentrated Sulfuric Acid F. Organic Solvents (, etc.)

IV. Elemental Analysis A. Sodium Fusion 1. nitrogen a. p-nitrobenzaldehyde in DMSO b. Prussian blue test 2. sulfur a. sodium nitroprusside test b. lead acetate test c. p-nitrobenzaldehyde in DMSO 3. halogens a. silver halide test b. oxidation of halide ion B. Beilstein Test for Halogens C. Metals and Other Inorganic Elements 1. qualitative inorganic analysis schemes 2. spectral tests

V. Spectroscopy A. IR B. NMR C. Others (UV, mass spectroscopy, etc.)

VI. Chemical Classification Tests A. 1. none B. and 1. bromine/carbon tetrachloride 2. Baeyer test C. Aromatic Hydrocarbons 1. aluminum chloride/chloroform D. Halides 1. Beilstein test 2. ethanolic silver 3. sodium iodide/acetone E. 1. Lucas test 2. chromic acid 3. acetyl chloride 4. iodoform test F. 1. ferric chloride solution 2. bromine water 3. acetyl chloride 4. colored phenoxide ion G. 1. none H. and 1. 2,4-dinitrophenylhydrazine 2. iodoform test 3. ferric chloride solution (for compounds with high enol content) 4. For Aldehydes Only a. chromic acid b. Tollens’ test c. Benedict’s test I. Carboxylic Acids 1. sodium bicarbonate solutions 2. ethanolic silver nitrate

J. 1. nitrous acid 2. acetyl chloride 3. Hinsberg test K. Nitro Compounds 1. ferrous hydroxide test L. 1. ferric hydroximate test 2. ammonia liberation from base hydrolysis M. 1. ferric hydroximate test N. 1. ferric hydroximate test 2. ammonia or amines liberated from base hydrolysis O. Acid Chlorides 1. ferric hydroximate test 2. ethanolic silver nitrate P. Acid Anhydrides 1. ferric hydroximate test Q. Others such as , quinones, sulfonamides, etc.

VII. Preparation of Derivatives A. Alkanes 1. none B. Alkenes and Alkynes 1. none C. Aromatic Hydrocarbons 1. side chain oxidation 2. nitro derivatives D. Halides 1. none E. Alcohols 1. 3,5-dinitrobenzoates 2. phenylurethanes 3. -naphthylurethanes F. Phenols 1. same as alcohols 2. bromo derivatives

G. Ethers 1. bromo derivatives (if aromatic ether) H. Aldehydes and Ketones 1. 2,4-dinitrophenylhydrazones 2. semicarbazones 3. I. Carboxylic Acids 1. amides 2. anilides 3. p-toluidides 4. neutralization equivalent J. Amines 1. benzamides 2. benzenesulfonamides 3. acetamides 4. methiodides 5. picrates K. Nitro Compounds 1. reduction to amines ( derivatives) 2. nitro derivatives (if aromatic ) L. Nitriles 1. hydrolysis to carboxylic acids ( derivatives) M. Esters 1. transesterification to derivatives 2. hydrolysis to carboxylic acids and alcohols (carboxylic acid and alcohol derivatives) 3. saponification equivalent N. Amides

1. hydrolysis to carboxylic acids and amines or NH3 (carboxylic acid and amine derivatives) O. Acid Chlorides 1. same as carboxylic acid derivatives 2. hydrolysis to carboxylic acids P. Acid Anhydrides 1. same as acid chloride derivatives

VIII. Confirmation of Identity A. Comparison to an "Authentic" Sample 1. physical properties and constants 2. IR and NMR spectra