2ALKYL GROUPSAn alkyl group is an unbranched alkane with a hydrogen atom removed from the terminal, or end, carbon.To name the alkyl group, replace the –ane ending of the unbranched alkane with –yl.Thus, if you take one hydrogen from CH4, it becomes —CH3, and the name changes from methane to methyl.
3NAMES OF ALKANES and ALKYL GROUPS Molecular FormulaStructural FormulaAlkylMethaneCH4MethylCH3EthaneC2H6CH3CH3EthylC2H5PropaneC3H8CH3CH2CH3PropylC3H7ButaneC4H10CH3(CH2)2CH3ButylC4H9PentaneC5H12CH3(CH2)3CH3PentylC5H11HexaneC6H14CH3(CH2)4CH3HexylC6H13HeptaneC7H16CH3(CH2)5CH3HeptylC7H15OktaneC8H18CH3(CH2)6CH3OktylC8H17NonaneC9H20CH3(CH2)7CH3NonylC9H19DekaneC10H22CH3(CH2)8CH3DekylC10H21UndekaneC11H24CH3(CH2)9CH3UndekylC11H23DodekaneC12H26CH3(CH2)10CH3DodekylC12H25
5Carbon atoms are classified as primary, secondary, tertiary, or quaternary based on the number of non-hyrogen groups attached to the sp3 carbon.The hydrogen atoms attached to these carbon atoms are given the same designation.
6Primary,secondary and tertiary carbon atoms Organic compounds often contain functional groups bonded on to different types of carbon chains.These can often be usefully distinguished using the terms primary,secondary and tertiary.Primary means that the carbonthat the functional group is joined to is bonded to only one other carbon atomSecondary means that it is bondedto two other carbon atomsTertiary three other carbon atoms.
10TRIVIAL(COMMON) AND IUPAC NAMES OF COMMON ALKYL GROUPS
11PENTYL GROUPSThere are eight different pentyl groups (-C5H11), but only four of these have trivial names. These four are shown above.
12ALKYL GROUPNote that an alkyl group (CnH2n+1, like an alkane with one H removed) can be represented by R.Thus alcohols (which contain the hydroxyl group — OH) can be represented as ROH.Similarly the benzene ring can be represented as so that phenol (a benzene ring with an — OH attached) is represented as
13ALKENYL GROUPAn alkenyl group is a hydrocarbon group formed when a hydrogen atom is removed from an alkene group.Alkenyl compounds are named by replacing the -e from the parent alkene's name with -yl.H2C=CH- (ethenyl or commonly known as vinyl). The parent alkene was H2C=CH2, ethene.
14ALKYNYL GROUPAn alkynyl group is a hydrocarbon group formed when a hydrogen atom is removed from an alkyne group.Alkenyl compounds are named by replacing the -e from the parent alkyne's name with -yl.ethynyl group, H C C derived from ethyne, H C C H is also called ethynyl radical.
15AROMATICS (ARENES)Arenes are cyclic hydrocarbons that contain three single bonds and three double bonds conjugated in a six-carbon ring.Arenes are usually derived from benzene.Another commonly used name for arenes is aromatic hydrocarbons.Arenes are cyclic hydrocarbons with alternating single and double bonds.Aromatic hydrocarbons are arenes based on benzene.
16BENZENE DERIVATIVESThe nomenclature of substituted benzene ring compounds is less systematic than that of the alkanes, alkenes and alkynes.A few mono-substituted compounds are named by using a group name as a prefix to "benzene", as shown by the combined names listed below.A majority of these compounds, however, are referred to by singular names that are unique.There is no simple alternative to memorization in mastering these names.
18ARYL GROUParyl group , in chemistry, group of atoms derived from benzene or from a benzene derivative by removing one hydrogen that is bonded to the benzene ring.The simplest aryl group is phenyl, C6H5 ; it is derived from benzene.
19ALKYL, ALKENYL, ALKYNYL and ARYL GROUPS HydrocarbonsGroups after one hydrogen removedName of the GroupFormulaName of the CompoundName of the SubstituentAlkaneCH4MethaneAlkylCH3 –MethylC2H6EthaneC2H5 –EtihylCyclohexaneCyclohexylAlkeneCH2 = CH2EteneAlkenylCH2 = CH –Ethenyl(Vinyl)– CH = CH – CH31-PropenylCH2 = CH – CH3PropeneCH2 = CH – CH2 –2-Propenyl (Allyl)AlkyneCH CHEthyneAlkynylCH C –EthynylCH C – CH3PropyneCH C – CH2 –PropynylAreneBenzeneArylPhenylTolueneBenzylNaphtalinenaphthylCH3CH2
20FORMATION OF ALKANES AND ARENES Alkyl, Alkenyl, Alkynyl and Aryl groups are not stable enough to exist as alone.Their tendency is to join other groups and this bonding tendency is the basis of synthetic organic chemistry.When alkyl groups join with each other alkanes will form:CH3-CH CH3CH2-CH2CH CH3CH2- CH2CH2CH3Ethane Butane PentaneWhen alkyl groups joined to aryl groups arenes will form. When we are naming arenes (aromatic hydrocarbons) first the name of alkyl group is said then the word benzene is added:Methylbenzene ( Toluene ) EthylbenzeneC2H5CH3
21FORMATION OF POLYCYCLIC ARENES When aryl groups join to each other polycyclic arenes (polycyclic aromatic hydrocarbons) will form.These compounds are named by using their common names.AnthraceneNaphtaline
22FORMATION OF ALKENESWhen alkyl groups join to alkenyl groups alkenes will form. 2-propenyl (CH2 = CH – CH2 -) and methyl ( CH3-) groups join 1- butene will form:CH2 = CH – CH2 – CH3When we are naming alkenes according to IUPAC (Systematic Naming) rules number the carbons in the chain so that the double bond would be between the carbons with the lowest designated number.When writing the name of the compound:first the lower number of the carbon atom which makes the double bond is written thena hyphene (-) is drawn andfinally the name of the alkene corresponding to the parent chain( the longest continuous chain of carbons that have the double bond) is written.CH2 = CH – CH2 – CH CH3- CH=CH - CH31- butene butene
25FORMATION OF ALKYNESWhen alkyl groups join to alkynyl groups alkynes will form.For example: ethyl (C2H5-) and propynyl (CH C – CH2 -) groups joined to each other 1-pentyne will form:CH C – CH2 – CH2 – CH3
26NAMING ALKYNES1. Identify the longest continuous chain of carbon atoms that contains the carbon-carbon triple bond. The parent name of the alkyne comes from the IUPAC name for the alkane of the same number of carbon atoms, except the - ane ending is changed to - yne to signify the presence of a triple bond. Thus, if the longest continuous chain of carbon atoms containing a triple bond has five atoms, the compound is pentyne.2. Number the carbon atoms of the longest continuous chain, starting at the end closest to the triple bond. Thus,is numbered from right to left, placing the triple bond between the second and third carbon atoms of the chain. (Numbering the chain from left to right incorrectly places the triple bond between the third and fourth carbons of the chain.)
27Naming Alkynes3. The position of the triple bond is indicated by placing the lower of the pair of numbers assigned to the triple-bonded carbon atoms in front of the name of the alkyne. Thus the compound shown in rule 2 is 2-pentyne.4. The location and name of any substituent atom or group is indicated. For example, the compoundis 5-chloro-2-hexyne.
28ALKYL HALIDES AND ALCOHOLS When halogens and alkyl groups join to each other alkyl halides will form.In the functional groups table - I we can see ethyl bromide as an example of an alkyl halide.Similarly when hydroxide and alkyl groups join to each other alcohols will form.In the functional groups table - I we can see propyl alcohol or propanol (C3H7 - OH) as a combination of a propyl (C3H7 -) and hydroxide(- OH) groups.When we are naming alcohols in common naming syste,first the name of alkyl group is written than the family name alcohol is added.
29FUNCTIONAL GROUPSAlkyl groups can also join with halogens and other atoms or atom groups to form organic ompounds other than hydrocarbons.Groups that are joined to alkyl grous which have tendency to react chemically are called Functional Groups.Functional groups will be represented in a table in the next two slides. The R, R',R1,R2,R3 and R4 written as bold represent different alkyl groups.But R not written as bold are generally represent alkyl groups and in some special cases it may be hydrogen,H.
30Formula of the Compund as an Example NAMES AND FORMULAS OF COMMON FUNCTIONAL GROUPS AND DERIVED COMPOUNDS - IFunctionalGroups inCompoundsFamily NameGeneral FormulaFormula of the Compund as an ExampleName of the Compound RAlkaneR H or R RCH3 – CH3Ethene C = C AlkeneR2 R1 HC = CH R3 R4CH3CH2CH = CHCH2CH33-hexene C C AlkyneR1 C C R2C2H5 – C C – CH32-pentyneAreneMethyl benzene(Toluene) X(-F, -Cl, Br, -I)AlkylHalideR – XC2H5 – BrEthyl bromide OHAlcoholR – OHC3H7 – OHPropyl alcohol(propanol) O EtherR – O – R'CH3 – O – CH3Dimethyl etherAldehydeAcetaldehydeKetonePropanone(dimethyl ketone)RCH3OCHCH3OCHOCHROCOCCH3OCR'R
31Functional Groups in Compounds Formula of the Compund as an Example NAMES AND FORMULAS OF COMMON FUNCTIONAL GROUPS AND DERIVED COMPOUNDS - IIFunctional Groups in CompoundsFamily NameGeneral FormulaFormula of the Compund as an ExampleName of the Compoundcarboxylic acidPropanoik acidAminePropylamineNitro alkaneNitromethane C NNitrileR C NCH3 C NEthanenitrileEsterEthyl ethanoateAmideacetamide(Ethanamide)Acyl halideacetyl chlorideOCOHOCOHROCC2H5OHHNHNRHNC3H7ONONCH3ONROCOCRR'OCC2H5OCH3OCNHOCNRHOCCH3NHOCXOCXROCCH3Cl
34LEARNING CHECK CH3 – CH2 – C C – C2H5 Draw the stuructural formula and write the name of the compound made of ethyl(-C2H5) and butenyl(CH2 = CH – CH2 – CH2-) grops.Draw the stuructural formula of 2- pentene.Draw the stuructural formula of isobutyl chloride.Write the IUPAC name of the structure:CH3 – CH2 – C C – C2H5Draw the stuructural formula and then write the name of the compound when the alkyl group 1,1-Dimethylethyl and hydroxylgroup (- OH) join to each other.CCH3
35PHYSICAL PROPERTIES OF HETEROATOMIC ORGANIC COMPOUNDS Heteroatomic groups like hydroxide(- OH), formyl(- CHO) and caboxyl(-COOH) can join to alkyl groups.The physical properties of these heteroatomic compounds are different than that of hydrocarbons having the same number of carbon atoms.Due to changes in intermolecular forces based on mass,volume and polarity changes) physical properties will change.Alcohols,aldehydes and carboylic acids have higher melting and boiling points than alkyl halides having the same number of carbon atoms due to addition of hydrogen bonding to dipole-dipole interactions.(Remember hydrogen bonding is stronger interaction than dipole-dipole forces.)
36LEARNING CHECK Name m.p (ºC) b.p (ºC) Butane - 138 - 0.5 Butanol - 88.6117.7Etoxyethane(Dimethyl ether)- 11634.6Butylamine- 5178Try to explain the differences in melting and boiling points of the compounds in the given table by comparing their intermolecular forces.
37PHYSICAL PROPERTIES OF HETEROATOMIC ORGANIC COMPOUNDS When heteroatomic groups like hydroxide(- OH), and caboxyl (- COOH) join to alkyl groups solubility in water will increase since these hydrophilic groups are polar.Hydrofobic group Hydrophilic groupCH3- CH2- CH OHpropopyl alcoholCH3- CH2- CH COOHbutanoic acidOn the other hand hydrocarbons having the same number of carbon atoms with alcohols and carboxylic acids do not dissolve in water since hydrophobes are nonpolar molecules.
38CHEMICAL PROPERTIES OF HETEROATOMIC ORGANIC COMPOUNDS When heteroatoms are joined to alkyl groups chemical reactivity will be greater than the hydrocarbons having the same number of carbon atoms.Saturated hydrocabons(Alkanes) can only give substitution and combustion reactions.Alkenes and Alkynes are more reactive than alkanes due to existance of pi bonding.So they can also give addition reactions.Heteroatomic organic compounds can give other types of reactions due to polar character of heteroatomic part.
39CHEMICAL PROPERTIES OF HETEROATOMIC ORGANIC COMPOUNDS Funcional groups can be cations and anions in chemical reactions.Acetyl group in the compound H3C – CO – Cl act as a cation since acetyl chloride molecule is polar.Cl is partial negative and C is partial positive.In the compound Li – CH3 methyl group act as an anion,since methyl lithium molecule is polar.CH3 is partial negative and Li is partial positive.Li CH LiCH3Lithium Methyl Methyl lithiumcation anionOC+CH3ClAcetyl cationChlorine anionCClAcetyl chloride
40CHEMICAL PROPERTIES OF HETEROATOMIC ORGANIC COMPOUNDS In the polar compound Methyl fluoride (Fluoromethane) CH3F methyl group act as a cation and fluorine act as an anion.CH F CH3FMethyl Fluorine Methyl fluoridecation anion
41NAMING OF DIOLS AND TRIOLS Diols, hydroxyaldehydes , hydroxyketones,dicarbonyls,hydroxyacids,ketoacids and dicarboxylic acids are the examples of organic compunds having more than one functional groups.Diols (glycols) have two hydroxide (-OH) groups but triols (glycerine) have three hydroxide groups.When naming these compounds the longest continuous chain having hydroxide groups is chosen and numbering should start from the end closer to hydroxide group.After writing the numbers of carbon atoms bonded to hydroxide groups a hyphen is drawn and then the name of the hydrocarbon is written according to the number of carbon atoms in the longest chain.Finally the word diol or triol is added if the molecule has two or three hydroxide groups respectively.CH2OH211,2-Ethanediol(Glycol)CH2OH321,2,3-Propanetriol(Glycerine)CHOH1
42NAMING OF HYDROXYALDEHYDES AND HYDROXYKETONES Hdroxyaldehdes and hdroxyketones have both hydroxide (- OH) and carbonyl( C=O ) groups.When naming these compunds the carbon atom having the double bonded should be located to the lowest possible number.4-Hydroxy-4-methyll-pentane-2-on(Diaceton alcohol)CCH3O12CH23OH453-HydroxybutanalCHCH3OH12CH23COH4
43NAMING OF DICARBONYL COMPOUNDS Dicarbonyl compounds are dialdehydes,aldehyde-ketone and diketones.When naming these compounds the longest chain is numbered in such away that the carbonyl group should be located to the lowest possible number.After writing the numbers of carbon atoms bonded to oxygen atoms a hyphen is drawn and then the name of the hydrocarbon is written according to the number of carbon atoms in the longest chain.Finally do not forget to add the suffixes - dione,- trione,- dial and – trial depending on the the type and number of functional groups.–al suffix will be used for aldehyde and -one suffix will be used for ketone.1,4-ButanedialSuccinindialdehydeCHO31CH2242,4-PentandioneAcetylacetoneCCH3O12CH2345
44NAMING OF KETOACIDSKetoacids are the carbonyl group containing carboxylic acids.When naming these compounds the longest chain is numbered in such a way that the carboxylic acid should be located to the lowest possible number.Carbonyl group is defined by oxo- (=O) prefix.Write the name of the hydrocarbon according to the number of carbon atoms in the longest chain and then add the suffix –oic acid.OCCH3COOH2-Oxopropanoic acidPirüvik asi4OCCH3CH23-Oxobutanoic acidAcetoacetic acidCOOH321
45NAMING OF HYDROXYACIDS Hydroxy acids are the compounds having both hydroxyl(-OH) and carboxyl (-COOH) groups.When naming these compounds the longest chain is numbered in such a way that the carboxylic acid should be located to the lowest possible number.After writing the number of carbon atom which is bonded to hydroxyl group a hyphene is added.Then hydroxy prefix is written, the name of the hydrocarbon according to the number of carbon atoms in the longest chain and the suffix –oic acid is added.COOH2,3-Dihydroxyibutanedioic acidTartaric acidCOHHCOOH2-Hydroxypropanoic acidLactic acidCOHHCOOHHydroxybutanedioic acidMalic acidCOHHCH2
46NAMING OF DICARBOXYLICACIDS Dicarboxylic acids are the compounds having two carboxyl groups in their molecules.When naming them, write the name of the hydrocarbon according to the number of carbon atoms in the longest chain and then add the suffix –dioic acid.Butanedioic acidSuccinic acidCOHOCH2Ethanedioic acidOxalic acidCOHO
47CONDENSED STRUCTURAL FORMULAS Chemical structures may be written in more compact forms, particularly when showing organic molecules.In condensed structural formulas, many or even all of the covalent bonds may be left out, with subscripts indicating the number of identical groups attached to a particular atom.Two varieties of condensed structural formula, both showing butane:
48SKELETAL ( BOND-LINE ) FORMULA Another shorthand structural diagram is the skeletal formula (also known as a bond-line formula or carbon skeleton diagram).In skeletal formulae, carbon atoms are not signified by the symbol C but by the vertices of the lines.Hydrogen atoms bonded to carbon are not shown — they can be inferred by counting the number of bonds to a particular carbon atom — each carbon is assumed to have four bonds in total, so any bonds not shown are, by implication, to hydrogen atoms.A skeletal diagram of butane:
49SKELETAL ( BOND-LINE ) FORMULA For example, in the image below, the skeletal formula of hexane is shown.The carbon atom labelled C1 has only one bond shown to it, so there must also be three hydrogens bonded to it, in order to make its total number of bonds four.The carbon atom labelled C3 has two bonds to other carbons and is therefore bonded to two hydrogen atoms as well.
50BALL-AND-STICK MODELA ball-and-stick model of the actual molecular structure of hexane, as determined by X-ray crystallography, is shown for comparison, in which carbon atoms are depicted as black balls and hydrogen atoms as white ones.
51COMPARISON OF DIFFERENT MODELS Shown below for comparison are a ball-and-stick model of the actual three-dimensional structure of the ethanol molecule in the gas phase (determined by microwave spectroscopy, left), the Lewis structure (centre) and the skeletal formula (right).
52BOND-LINE FORMULAS OF SOME ORGANIC COMPOUNDS Bazı organik bileşiklerin iskelet (çizgi-bağ) formülleriName of the compoundMolecular formulaStuructural FormulaBond-Line FormulasIsohexaneC6H14Ethyl acetate(Ethyl ethanoate)CH3CO2C2CH5AcetophenoneC6H6COCH3NeopentaneC5H12CH3CHCH2CH3OCH2COCCH3OOCH3C
53LEARNING CHECKName the following compounds represented by the bond- line formulas:Draw the stuructural formulas of the following compounds and then write their bond-line formulas:a) ethyl ethanoateb) 1- aminobutanec) 2- chloro- 4 - methylheptaneOH