Organic ChemistryOrganic Chemistry
Topic 10 Topic 10
Uniqueness of carbonUniqueness of carbon
Up to 4 bonds with other atomsUp to 4 bonds with other atoms Single, double and triple bondsSingle, double and triple bonds Stable covalent bonds C-C or C-HStable covalent bonds C-C or C-H Can form chains and ringsCan form chains and rings Octet cannot expand so not as Octet cannot expand so not as
reactivereactive
Describe the features of an Describe the features of an homologous serieshomologous series
Organic means carbon based Organic means carbon based compoundscompounds
Alkanes C, H all single bondsAlkanes C, H all single bonds CCnnHH2n+22n+2
Alcohols have OH group bonded to CAlcohols have OH group bonded to C CCnnHH2n+12n+1OHOH
Features of an homologous seriesFeatures of an homologous series
Same functional groupSame functional group Same general formulaSame general formula Successive members add CHSuccessive members add CH22
Gradation of physical propertiesGradation of physical properties Similar chemical propertiesSimilar chemical properties Question 1 and 2Question 1 and 2
Longer chains are stickier and Longer chains are stickier and have higher boiling points (bp)have higher boiling points (bp)
Question 3Question 3
FormulasFormulas
ethaneethane Empirical CHEmpirical CH33
Molecular CMolecular C22HH66
Structural full and condensedStructural full and condensed
animationanimation
Try ethanoic acidTry ethanoic acid
Try glucose empirical formula CHTry glucose empirical formula CH22O O M Mrr = 180 = 180
conventionsconventions
R or RR or R‘ used for hydrocarbon part‘ used for hydrocarbon part ROHROH Benzene ringBenzene ring
4 single bonds is tetrahedral 109.54 single bonds is tetrahedral 109.5oo not 90not 90oo, tetrahedral, tetrahedral
3 bonds no lone pairs form 1203 bonds no lone pairs form 120oo, , triangular planertriangular planer
Sterochemical formula wedge = Sterochemical formula wedge = forward of a page, dotted line = forward of a page, dotted line = behindbehind
nomenclaturenomenclature
Learn names of 1-6 carbonsLearn names of 1-6 carbons Page 370 in your bookPage 370 in your book
Rule #1 Name the longest chainRule #1 Name the longest chain Build pentane and show how it Build pentane and show how it
rotates around a single bondrotates around a single bond
`̀
#2 Use the functional group ending #2 Use the functional group ending as the suffix of the name page 371 in as the suffix of the name page 371 in the bookthe book
-ane, -ene, -anol,-anone, -anoic acid-ane, -ene, -anol,-anone, -anoic acid
Name the side chainName the side chain Methyl, ethyl, propylMethyl, ethyl, propyl Build 2-methyl butaneBuild 2-methyl butane This is an isomer of pentaneThis is an isomer of pentane Use the lowest # possible to number Use the lowest # possible to number
the carbon it is onthe carbon it is on What is 4-methyl pentane?What is 4-methyl pentane?
Use prefixes di-, tri-,tetra- to Use prefixes di-, tri-,tetra- to represent more than one side chain represent more than one side chain in alphabetical orderin alphabetical order
1,2 dichloropropane1,2 dichloropropane
1-chloro-2-methylpropane (notice 1-chloro-2-methylpropane (notice alphabetical order)alphabetical order)
Propan-2-olPropan-2-ol
But-1-eneBut-1-ene
If a functional group can only be in If a functional group can only be in one place leave off the numberone place leave off the number
Like propeneLike propene
Butanoic acidButanoic acid
PropanonePropanone
Name the following a) CHName the following a) CH33CHCH22CHCH22COOH COOH
b) CHClb) CHCl22CHCH22CHCH33
c) CHc) CH33CHCH22COCHCOCH33
Draw the structural formulas of the Draw the structural formulas of the following molecules a) hexanoic following molecules a) hexanoic acid acid
b) butanalb) butanal
Do questions 4-6Do questions 4-6
Handout on nomenclatureHandout on nomenclature
Do questions 1-4 pages 374-5Do questions 1-4 pages 374-5
Aromatic groupsAromatic groups Para dichloro benzenePara dichloro benzene
Structural isomersStructural isomers
Same molecular formula, different Same molecular formula, different arrangement of atomsarrangement of atoms
Different structural formulaDifferent structural formula Butane and 2-methylpropaneButane and 2-methylpropane
Draw and name all the isomers of Draw and name all the isomers of pentanepentane
Start with the straight chain and Start with the straight chain and progressively pull off the endsprogressively pull off the ends
Draw and name all the isomers of Draw and name all the isomers of CC66HH1414
Structural isomers in alkStructural isomers in alkeenesnes
Draw and name the isomers of CDraw and name the isomers of C44HH88
Draw and name the straight chain Draw and name the straight chain isomers of Cisomers of C66HH1212
Classes of compoundsClasses of compounds
Primary, secondary, tertiaryPrimary, secondary, tertiary To how many carbons is the carbon To how many carbons is the carbon
attached to the functional group attached to the functional group attachedattached
EthanolEthanol
Propan-2-olPropan-2-ol
2-methylpropan-2-ol2-methylpropan-2-ol
Trends in physical propertiesTrends in physical properties
Volatility (how easily evaporated)Volatility (how easily evaporated) Smaller less stickySmaller less sticky Branched less stickyBranched less sticky Animation 1Animation 1 Functional polar groups more sticky Functional polar groups more sticky
less volatileless volatile
alkanealkane>halogenoalkane >aldehyde >halogenoalkane >aldehyde >ketone >alcohol >acid>ketone >alcohol >acid
Solubility in waterSolubility in water
More polar more solubleMore polar more soluble Alcohol, aldehyde, ketone and acid Alcohol, aldehyde, ketone and acid
are all solubleare all soluble
Which compound has the Which compound has the lowest boiling point? lowest boiling point? CH3CH2CH(CH3)CH3 CH3CH2CH(CH3)CH3 (CH3)4C CH3CH2CH2CH2CH3 (CH3)4C CH3CH2CH2CH2CH3 CH3CH2OCH2CH3CH3CH2OCH2CH3
Do questions 8 and 9Do questions 5-8 page 382 for HW
10:2 Alkanes10:2 Alkanes
CCnnHH2n+22n+2
SaturatedSaturated HydrocarbonsHydrocarbons Strong bonds – low reactivityStrong bonds – low reactivity However, they burn easily forming However, they burn easily forming
COCO22 and H and H22OO If not enough OIf not enough O22 they form CO or C they form CO or C
(soot)(soot)
Show the equation for burning Show the equation for burning octaneoctane
Halogenation of alkanes page 384 in Halogenation of alkanes page 384 in your bookyour book
UV light and ClUV light and Cl22 yields 2 Cl yields 2 Cl.. Radicals Radicals
Called homolytic fissionCalled homolytic fission
Propagation or chain reactionPropagation or chain reaction
Show termination stepShow termination step
Do this all with molecular Do this all with molecular modelsmodels
Do question set 1 for homeworkDo question set 1 for homework
Ready for a quiz???Ready for a quiz???
10:3 Alkenes10:3 Alkenes
Unsaturated hydrocarbonsUnsaturated hydrocarbons = bond has a weak pi( )= bond has a weak pi( )bond along bond along
with the sigma (with the sigma (σσ))
Addition reactionsAddition reactions
Ni catalyst and HNi catalyst and H22
Used in margarine to make saturated Used in margarine to make saturated fats with higher melting pointsfats with higher melting points
Reaction with halogensReaction with halogens Propene with BrPropene with Br2 2 (test for a = bond) (test for a = bond)
Hydrogen halides Hydrogen halides
Produce halogenoalkanesProduce halogenoalkanes Propene with HClPropene with HCl
HI weaker bonds more reactive than HI weaker bonds more reactive than HBr then HClHBr then HCl
Reaction with waterReaction with water
Called hydrationCalled hydration Alkene to alcoholAlkene to alcohol Use conc. HUse conc. H22SOSO44 as a catalyst and as a catalyst and
steamsteam Ethene to ethanol (industrial use to Ethene to ethanol (industrial use to
get alcohol)get alcohol)
polymerizationpolymerization
PolyethylenePolyethylene Monomer isMonomer is
Polymer isPolymer is
Polyvinylchloride (PVC)Polyvinylchloride (PVC)
Teflon (polytetrafluoroethene) what Teflon (polytetrafluoroethene) what is the starting material?is the starting material?
Do questions 10-12Do questions 10-12
10:4 alcohols10:4 alcohols
CCnnHH2n+12n+1OHOH Nomenclature handout alcoholsNomenclature handout alcohols -OH (hydroxyl group) functional -OH (hydroxyl group) functional
groupgroup Shorter chains soluble in waterShorter chains soluble in water
combustioncombustion
Like alkanesLike alkanes Equation for burning of ethanolEquation for burning of ethanol
Longer chains give off more energyLonger chains give off more energy
oxidationoxidation
Alcohols with orange KAlcohols with orange K22CrCr22OO7 7 reduce it to reduce it to green Crgreen Cr22OO33 (breathalyzer test) (breathalyzer test)
Primary alcohols oxidize to aldehyde Primary alcohols oxidize to aldehyde then to acidsthen to acids
Ethanol with KEthanol with K22CrOCrO7 7
Distill to get ethanal (apple smell)Distill to get ethanal (apple smell)
Reflux to get acidReflux to get acid Lab activity distillation and refluxingLab activity distillation and refluxing
Secondary alcohols make ketonesSecondary alcohols make ketones Propan-2-ol (reflux) Propan-2-ol (reflux)
Tertiary alcohols do not readily Tertiary alcohols do not readily oxidizeoxidize
Do questions 13-14Do questions 13-14 Do question set 2 for homeworkDo question set 2 for homework
10:5 Halogenoalkanes10:5 Halogenoalkanes
CCnnHH2n+12n+1X X = halogenX X = halogen Used as intermediaries in other Used as intermediaries in other
reactionsreactions Polar CPolar Cδδ++ - Cl - Clδδ- - C e- deficientC e- deficient Nucleophiles e- rich lone pairs Nucleophiles e- rich lone pairs
attack the e- deficient areaattack the e- deficient area SSNN substitution nucleophile reactions substitution nucleophile reactions
Examples of nucleophiles HExamples of nucleophiles H22O OHO OH-- NHNH33 CN CN--
SN2 (bimolecular) primary SN2 (bimolecular) primary halogenoalkaneshalogenoalkanes
SSNN1 tertiary halogenoalkanes1 tertiary halogenoalkanes UnimolecularUnimolecular Secondary halogenoalkanes can Secondary halogenoalkanes can
undergo eitherundergo either
Go to page 395 and draw the 2 Go to page 395 and draw the 2 mechanisms showing curly arrowsmechanisms showing curly arrows
AnimationAnimation Do questions 15-17Do questions 15-17
10:6 Reaction pathways 10:6 Reaction pathways
see page 406 in the textbook fill in see page 406 in the textbook fill in the reagents and conditions neededthe reagents and conditions needed
Convert 1-chlorobutane into butanoic Convert 1-chlorobutane into butanoic acid acid
Do proponal from 1-bromopropaneDo proponal from 1-bromopropane
1,2,3 trichlorpropane from propene1,2,3 trichlorpropane from propene
EstersEsters Formed when organic acids react Formed when organic acids react
with alcoholswith alcohols Fragrances and flavorsFragrances and flavors RCOORRCOOR‘‘
Draw methyl methanoate from Draw methyl methanoate from methanol and ethanoic acidmethanol and ethanoic acid
Ester from methanoic acid and propanolEster from methanoic acid and propanol Name and draw the structureName and draw the structure Nomenclature handout estersNomenclature handout esters
Do question 7Do question 7 Ester labEster lab
Do questions 18-20Do questions 18-20 Do questions 1-4,6-9,11 pages 416 Do questions 1-4,6-9,11 pages 416
and 417 in your textbookand 417 in your textbook Do the SL questions (1-11) in your Do the SL questions (1-11) in your
study guide on page 74study guide on page 74 Homework question set 3Homework question set 3 Quiz 10:3-6Quiz 10:3-6