christian brothers high school department of chemistry organic chemistry ii

Christian BrothersHigh School

Department of Chemistry

Organic Chemistry II

Organic Reactions

• Much slower than inorganic reactions• Organic compounds can be toxic, but

effects are usually cumulative, i.,e., there must be long-term exposure

• Substitution • Addition• Formation of radicals and functional

groups

Organic ChemistrySubstitution Reactions I• Knock off one or more hydrogens• Substitute another radical or an oxygen, halogen,

sulfur, etc• Methane subst. 1 Cl for H= Chloromethane• Subst. One more Cl for H= dichloromethane

or methylene chloride• Subst. One more Cl for H= trichloromethane

or chloroform• Subst. One more Cl for H= tetrachloromethane or

carbon tetrachloride

Organic ChemistryFormation of Free

Radicals• Whenever a hydrogen atom is knocked off • Formation of a free radical• Always uses the –yl suffix to indicate the

radical• Functional group radicals also use the –yl suffix• In generic formulae use R ROH means any

alcohol• Bonds with other molecules and radicals to

form new compounds• Examples methyl- CH3 ethyl- C2H5

propyl- C3H7 butyl- C4H9

Organic ChemistryFunctional Groups

• Way of organizing different classes of compounds

• Identify by structure• -OH hydroxyl group Alcohols• -OOH carboxyl group

Organic Acids

Organic ChemistryAlcohols

• Generic formula ROH• Characterized by the hydroxyl group -OH• Industrial solvent, cleaner, intermediary in

reactions, beverages, miscible in water• Properties of alcohols are determined by where

the hydroxyl groups attached• Primary alcohol- hydroxyl group on the end• Secondary alcohol- hydroxyl group attached to

a carbon which is attached to one hydrogen• Tertiary alcohols- hydroxyl group attached to a

carbon which is in the middle of the chain

Organic ChemistryOrganic Acids

• Also known as carboxylic acids• Characterized by the carboxyl group –OOH• Examples Acetic Acid CH3COOH• A 3% aqueous solution of acetic acid is

vinegar• Butyric acid 4 carbons is produced by

the spoiling of milk• Longer chain acids (primarily C18 with one or

more double bonds are called polyunsaturated fatty acids)

Organic ChemistryOrganic Bases

• Organic bases are known as amines• Primary amines have radicals substituted

for the hydrogens on the ammonia molecule

• Methylamine 1 methyl group• Dimethylamine 2 methyl groups• Triethylamine 3 ethyl groups

• Other amines have the nitro group (NH2) substituted on other radicals

Organic ChemistryOther Functional Groups

• Aldehydes and Ketones both contain the carbonyl group -C=O

• Aldehydes have the group attached to a hydrogen at the end of a chain H-C=O

• Ketones have the group attached to two carbons (See board)

• Ethers R-O-R

• Diethyl ether once used as a surgical anesthetic

Organic ChemistrySugars/Carbohydrates

• Energy source in animal metabolism

• Always end in –ose• Simple sugars

• Fructose• Glucose• Sucrose• Lactose

• Complex Carbohydrates

• Increasing stacking of rings

• Long stacks of rings

• Cellulose (plant fiber)

• Wood

Organic ChemistryProteins

• Enzymes• Structural Building Blocks• Amino Acids• Peptide backbone• Biomacromolecules (DNA)

Organic ChemistryPlastics (polymers)

• Built from simple compounds (monomers)

• Ethylene + initiator = polyethylene• Propylene + initiator = polypropylene• Butylene + initiator = polybutylene• Styrene + initiator = polystyrene• Vinyl chloride + initiator = polyvinyl

chloride