The study of carbon-based compounds and their properties.

Historically the distinction between inorganic and organic substances was based on whether or not they were produced by living systems. It was believed that some sort of “life force” was needed to synthesize them.

In 1828, the German chemist Freidrich Wohler (1800-1882) prepared urea from the inorganic salt ammonium cyanate by simple heating.

NH4OCN H2N—C—NH2

Ourea

Hydrocarbons: contain only hydrogen and carbon

HydrocarbonsAliphatic Aromatic

Alkanes Alkenes Alkynes Cyclic

Hydrocarbons can be divided into different types, depending on their bonding.

Alkanes - - Carbon chain, no double or triple bonds. All single bondsAlkenes - - Carbon chain, contains double bond(s)Alkynes - - Carbon chain, contains triple bond(s)

Naming Organic Molecules

Naming Organic Molecules

There are two parts to the main name of each molecule…

prefix: tells the # of carbons in main chain or ring

suffix: tells the type of bonding in the chain or ring

Prefix: indicates number of carbon atoms in the main chain or ring1 meth-

2 eth-3 prop-4 but-5 pent-

6 hex-7 hept-8 oct-9 non-10dec-

Suffix: indicates types of bonds presentAlkanes: (all single bonds) ___ -ane

Alkenes: (double bond) ___ -eneAlkyne: (triple bond) ___ -yne

For example…

For example…

For example…

Saturated Hydrocarbons contain only single C-C bonds

Unsaturated hydrocarbons: contain double or triple C-C bonds

Saturated Hydrocarbons: the ALKANES: chains of carbon

connected by single bonds:

ALKANESmethane, CH4

ALKANESethane, C2H6

ALKANESpropane, C3H8

ALKANESbutane, C4H10

ALKANESpentane, C5H12

ALKANEShexane, C6H14

ALKANESoctane, C8H18

“Normal” v. Branched “normal” hydrocarbons are straight

chains; no branching

Branched-chain hydrocarbons – isomers of “normal” hydrocarbons; have same formula, but different structures

n-butane

2-methlypropane

n-pentane

2-methylbutane

2,2-dimethylpentane

Cycloalkanes

cyclopentane

Unsaturated Hydrocarbons: ALKENES – contain C-C double bonds

2-pentene

Unsaturated Hydrocarbons: ALKENES – contain C-C double bonds

2,4-hexadiene

Unsaturated Hydrocarbons: ALKYNES – contain C-C triple bonds

1-butyne

Unsaturated Hydrocarbons: ALKYNES – contain C-C triple bonds

3-ethyl-1-pentyne

Aromatic Hydrocarbons:

benzene – the simplest aromatic hydrocarbon; has a symmetrical ring structure

Aromatic Hydrocarbons:

benzene – can be drawn like this…

Derivatives of benzene:

1-ethyl-2-methylbenzene

Derivatives of benzene:

1,2-dimethyl-4-propylbenzene

Functional Groups

Functional groups: special groups of atoms attached to a hydrocarbon skeleton; the most common sites of chemical reactivity.

Organic halides: a hydrogen is replaced by a halogenfluoro-, chloro-, bromo-, iodo-2-iodobutane

Organic halides: a hydrogen is replaced by a halogenfluoro-, chloro-, bromo-, iodo-2,4-dibromo-1-hexene

Organic halides: a hydrogen is replaced by a halogenfluoro-, chloro-, bromo-, iodo-1-bromo-2-chlorobenzene

Alcohols & phenols: contain the hydroxyl group (-OH)alcohols: at least 1 H on a hydrocarbon is replaced by OHphenols: at least 1 H on an aromatic ring is replaced by OH2-propanol

Alcohols & phenols: contain the hydroxyl group (-OH)alcohols: at least 1 H on a hydrocarbon is replaced by OHphenols: at least 1 H on an aromatic ring is replaced by OH3-methyl-1-butanol

Alcohols & phenols: contain the hydroxyl group (-OH)alcohols: at least 1 H on a hydrocarbon is replaced by OHphenols: at least 1 H on an aromatic ring is replaced by OH1,2-butanediol

ethers: compounds in which an O atom is bonded to 2 organic groups: -C-O-C-

methoxymethane (dimethyl ether)

ethers: compounds in which an O atom is bonded to 2 organic groups: -C-O-C-methoxypropane (methyl propyl ether)

ethers: compounds in which an O atom is bonded to 2 organic groups: -C-O-C-methoxybenzene (methyl phenyl ether)

amines: derivatives of ammonia (NH3) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups)

ammonia

amines: derivatives of ammonia (NH3) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups)

methylamine

amines: derivatives of ammonia (NH3) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups)

trimethylamine

amines: derivatives of ammonia (NH3) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups)

2-aminobutane

amines: derivatives of ammonia (NH3) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups)

1-amino-3-propylcyclohexane

*aniline: the simplest aromatic amine

aniline

*aniline: the simplest aromatic amine

3,5-dichloroaniline

*aniline: the simplest aromatic amine

N,N-dimethylaniline

Carboxylic acids: compounds that contain the carboxyl group (general formula is R-COOH)butanoic acid

Carboxylic acids: compounds that contain the carboxyl group (general formula is R-COOH)ethanoic acid

Carboxylic acids: compounds that contain the carboxyl group (general formula is R-COOH)3-methylpentanoic acid

Carboxylic acids: compounds that contain the carboxyl group (general formula is R-COOH)benzoic acid