Chapter 22

 Molecular -  Shows type & number of atoms in compound  Structural -  Shows bonding pattern & the shape of molecules

CH4CH4 C2H6C2H6 Structural Condensed Structural H H C H H H H H C C H H H CH4CH4 CH3CH3CH3CH3 Molecular Methane Ethane

 The study of carbon & most carbon compounds  Recall…  Carbon has 4 valence electrons  It can form 4 covalent bonds  Makes carbon a versatile atom  Hydrocarbons -  Compounds containing only C & H  Simplest organic molecules

Common Elements in Organic Compounds

 Alkanes - saturated  Alkenes - unsaturated  Alkynes – unsaturated  Saturated Molecules -  Contain only single bonds  Unsaturated Molecules -  Contain one or more double or triple bonds

 Hydrocarbon with only single covalent bonds  Saturated with H atoms  Formula is C n H 2n+2 where n = 1,2,3, etc.  As # of C increases, boiling point increases  Names end in –ane  Ex. methane (CH 4 ), ethane (C 2 H 6 ), propane (C 3 H 8 )

Physical Properties of Some Alkanes

 A group of related compounds in which each member differs from the previous compound by the same additional unit.  Members have related structures and properties  Ex. alkanes differ by groups of CH 2

 Table P  Prefix is based on the number of carbon atoms in a ‘chain’

 Alkanes  Use Table P to determine the prefix, based on the # of carbon atoms in the compound  End in -ane Hexane

Alkane Nomenclature 1.The parent name of the hydrocarbon is that given to the longest continuous chain of carbon atoms in the molecule. CH 3 CH 2 CHCH 2 CH heptane 2.An alkane less one hydrogen atom is an alkyl group. CH 4 CH 3 methane methyl 4-methylheptane

Alkane Nomenclature 3.When one or more hydrogen atoms are replaced by other groups, the name of the compound must indicate the locations of carbon atoms where replacements are made. Number in the direction that gives the smaller numbers for the locations of the branches. CH 3 CHCH 2 CH methylpentane CH 3 CH 2 CHCH methylpentane

Alkane Nomenclature 4.Use prefixes di-, tri-, tetra-, when there is more than one alkyl branch of the same kind. CH 3 CH CH 2 CH ,3-dimethylhexane CH 3 CH 2 C CH ,3-dimethylhexane

Alkane Nomenclature 5.Use previous rules for other types of substituents. CH 3 CH CH 3 Br 1234 NO 2 2-bromo-3-nitrobutane CH 2 CHCH 3 Cl 1234 F 1-chloro-3-fluorobutane

What is the IUPAC name of the following compound? CH 3 CHCH 2 CHCH 2 CH 3 C2H5C2H5 CH 2 CH 3 2-methyl-4-ethyloctane Draw the structural formula of 2-propyl-4-methylhexane CH 3 CHCH 2 CHCH 2 CH 3 C3H7C3H7

Give the IUPAC name of the following compound: Sample Exercise

Give the IUPAC name of the following compound:

2.Name the following: 3,4-dimethylheptane 2,4-dimethylpentane

3.Draw the complete structural formulas for the following compounds: a.3-ethylhexane b.2,2,4-trimethylpentane

1.Draw the structural formula of 5-ethyl-2,4,6-trimethyloctane.

4. Write the structural formulas for: a. 3-ethyl-2-methylpentane b. 2,3,-dimethylhexane c. 4-ethyl-2,3,4-trimethyloctane

 Hydrocarbon with at least one double covalent bond  Unsaturated with H atoms  Formula is C n H 2n where n = 2,3, etc.  Names end in -ene  Ex. ethene (C 2 H 4 ), propene (C 3 H 6 ), butene (C 4 H 8 )

 Alkenes  End in –ene  Number the location of the double bond CH 2 CHCH 2 CH 3 1-butene CH 3 CH CH 3 2-butene

 Hydrocarbon with at least one triple covalent bond  Unsaturated with H atoms  Formula is C n H 2n-2 where n = 2,3, etc.  Names end in -yne  Ex. ethyne (C 2 H 2 ), propyne (C 3 H 4 ), butyne (C 4 H 6 )

 Alkynes  End in –yne  Number the location of the triple bond 1-butyne2-butyne CH CCH 2 CH 3 CC

 Compounds with the same molecular formula but different structural formulas  Ex. C 4 H 10  Isomers have different chemical & physical properties  As the # of C atoms increase, the # of isomers increase (Straight-chain form) (branched-chain form)

Draw structural isomers for C 5 H 12 : CCCC C HHHHH H HHHHH H CCC C HCH 3 HH H HHHH H CC C H H H HH H pentane 2-methylbutane 2,2-dimethylpropane

Chapter 23

 A specific arrangement of atoms in an organic compound  Capable of characteristic chemical reactions  Aka the ‘chemically functional’ part of the molecule  Allows organic compounds to be classified

 R = carbon chain or rings attached to functional group

 Contain covalently bonded halogens:  F, Cl, Br, or I  Named by describing location of the halogen(s) attached to the chain H Cl Cl H H—C—C—C—C—H H Cl H H 2,2,3–trichlorobutane

 Contain a hydroxyl group: –OH  Alcohols are not electrolytes  Do not form ions/conduct electricity  Hydroxyl groups are polar  Allows alcohols to be soluble in water  To name: change the ending -e to –ol

Sample Problems Name the alcohol: Example 1 H H H H H—C—C—C—C—OH H H H H Name: 1–butanol CSF: CH 3 CH 2 CH 2 CH 2 OH

Example 2 H H H H H—C—C—C—C—H H H OH H Name: 2–butanol CSF: CH 3 CH(OH)CH 2 CH 3

Example 3 H H—C—H H H H H—C—C—C—C—H H H OH H Name: 2–methyl, 2-butanol CSF: CH 3 C(OH)(CH 3 )CH 2 CH 3

Example 4 H H H H H—C—C—C—C—OH H H OH H Name: 1,2–butanediol CSF: CH 3 CH 2 CH(OH)CH 2 OH

Example 5 H H OH H H—C—C—C—C—OH H H OH H Name: 1,2,2–butanetriol CSF: CH 3 CH 2 C(OH)(OH)CH 2 OH

Example 6 Draw and then name the following alcohol: CH 3 CH 2 CH 2 CH 2 CH 2 OH

 Contain a carbonyl group: -C=O  C is attached to at least one H at end of the molecule  Carbonyl groups are polar!!!  To name: propanal change the -e ending to -al R C H O aldehydes have the general formula

 Contain a carbonyl group: -C=O  C is joined to two other C’s in the middle of the molecule  To name: change the -e ending to -one R C R′ O ketones have the general formula

 Are compounds in which oxygen is bonded to two carbon groups  The groups attached to the ether linkage are names in alphabetical order and is followed by the word ether H H H–C–O–C–H H H dimethyl ether H H H H–C–O–C–C–H H H H ethyl methyl ether H H H H H–C–C–O–C–C–H H H H H diethyl ether

Functional Group Chemistry Ethers have the general formula R−O−R′. CH 3 OH + HOCH 3 CH 3 OCH 3 + H 2 O H 2 SO 4 catalyst Condensation Reaction

 Contains a carboxyl group: -COOH  Usually weak electrolytes  To name: change the -e ending to -oic acid propanoic acid

 Derivatives of a carboxylic acid & an alcohol  R-CO-OR’  To name: change -e ending to -oate

 Formed when 1 or more H atoms in ammonia (NH 3 ) are replaced with an alkyl group  To name: CH 3 CH 3 N CH 3 H CH 3 N CH 3 H CH 3 N H H H N H ammoniamethyl aminedimethyl aminetrimethyl amine change the -e ending to -amine & number the alkane chain to show where the amine group is located

 A carboxyl group: -COOH  An amine group: -NH 2  H atom  R group attach to a central carbon atom

 H atom in an amine group reacts with a –OH group of an organic acid  Occurs when two amino acids form a peptide bond

O CH 3 —C—NH 2 ethanamide O C 3 H 7 —C—NH 2 butanamide  To name: change the -e ending to -amide

 Identify the functional group in each structure: 1.CH 3 – OH 2.CH 3 – CH 2 – NH 2 3.CH 3 – CH 2 – CH 2 – Br 4.CH 3 – CH 2 – O – CH 2 – CH 3

 Burning a hydrocarbon in oxygen to produce water and carbon dioxide  If O 2 supply is limited CO may be produced instead of CO 2  Complete combustion  C 3 H 8 (g) + 5O 2 (g) —> 3CO 2 (g) + 4H 2 O(g)  Incomplete combustion  2C 3 H 8 (g) + 7O 2 —> 6CO(g) + 8H 2 O(g)

 Replacement of one or more of the H atoms in a saturated hydrocarbon with another atom or group  Ex. halogenation or hydrogenation  CH 4 + Cl 2  CH 3 Cl + HCl  C 2 H 6 + Cl 2  C 2 H 5 Cl + HCl  CH 3 I + KOH  CH 3 OH + KI

 The addition of one or more atoms to a double or triple bond

 Reaction between an organic acid and an alcohol to produce an ester plus water

 Reaction between an ester and an inorganic base to produce an alcohol and a soap  Ex. Fat + NaOH  soap + glycerol  In the soap–making process, an animal fat or vegetable oil is boiled with a strong base, NaOH

Fat + Alkali Glycerol +Soap →

 Reaction where yeast cells break down glucose into CO 2 and ethanol  C 6 H 12 O 6  2C 2 H 5 OH + 2CO 2

 Reaction where many monomers covalently bond to form a polymer  Polymer –  organic compounds made up of chains of smaller units covalently bonded together  Ex. proteins, starches, DNA

Addition Polymerization -  Reaction that joins monomers of unsaturated compounds  nC 2 H 2 —> (C 2 H 2 ) n H H H H H H C=C + C=C + C=C H H H H H H H H H – C-C –– C-C –– C-C – H H H H H H

Condensation Polymerization -  Reaction where monomers are joined together and a water molecule is released  Monomers form an ether or ester linkage

Chemistry In Action: The Petroleum Industry Crude Oil

Fractions Obtained from Crude Oil