p1 alkanes to aldehydes and ketones

7/30/2019 p1 Alkanes to Aldehydes and Ketones

1/53

SCH4U 1 Organic ChemistryPart 1 Alkanes to Aldehydes and Ketones


2/53

Saturated Aliphatic HydrocarbonsHydrocarbons are compounds that contain only carbon and hydrogen. Alkanes arehydrocarbons that only contain single bonds. Below are examples of molecularformula, structural diagrams and ball-and-stick diagrams for the first four alkanes.

methane IH-C-HICH4 HH H

ethane I IH -C -C - HI IC2H6 H H

H H Hpropane I I IH-C -C -C -HC3Hs I I IH H H

H H H Hbutane I I I IH -C -C -C -C -HC4H10 I I I IH H H H

Nomenclature1. Straight-Chained (or Normal) Alkanes, CnH2n+2

Number prefix line structural Number prefix line structuralof C diagram of C diagram

1 f ' l \ e - ~ t-J.A. 6 ~ e i ~e--tV\ ; ?.. J\tpt ~- - 7

3 yrop ~ 8 oc\- /V 'VV 'I 34 btA+ ~ 4 9 (\0 (\ / VVV \'5 r ~ ~ ) 10 d_Q_c /VVVV

1


3/53

22. Branched Alkanes, CnH2n+2

alkyl branches halogen branchesmethyl lf flu oro- -I+"' c r-Ilfethyl ~ t]4 c - c ->' (rl H- bromo- Br-propyl ~ rt HI :! t - - e - e - c . ~H H ,4

iodo- T-isopropyJ.f- fj M ~ rt-c - c - c-H {-- I+

cyclopropyl- ~ ' c " l - 1. " / 7I C- ...... c / \1-tOrder branches to give them the lowest numbers possible. The longest chain is thearent. Name the branches al habeticall .

2-methylhexane

Name these:

q- ~ \ 1-3,3-d f \ e t G \ _ ~ JCChr\ e

4-ethyl-3-methylheptane

7

/b

s ; ~ - d l e - \ t " 1 l ).lJ_); 4 + e t m n ' \ e ' t v ~ -7-- pR>p )d ecct ll'\ -e.


4/53

3. Alk C H2. CycliC ones, n n

~ D 0 0G ~ C \ o p 1 ~ t ~ d o o r x r a \ \ e c ~ c\cpert:ln e ~ dohek:aate

Order branches to give them the lowest numbers possible and number according tothe alphabet if possible:

1,1-dimethylcyclohexane 1-ethyl-2-methylcyclopenta ne

Name these:

172, y' s-- + e : h n e : \ t ~ j-3,-s.-d.l f Y \ ~ t t ' H \ c ~ c \ o -. hQ l(ctf\_e_


5/53

Chemical Reactions1. CombustionComplete combustion:

Incomplete combustion produces a mixture of:

2. Substitution by a Halogen: Only happens in light, as the mechanism needs a radical.It produces two products- an alkyl halide and a haloacidhv /f-c-H + ~ c t

ICJ-Cl l}v H- ' - - - - - ~ Cl -t Ct C-+v0o C ~ I \ Q t ' \ v \ e_ ~ c Q \ ~ JCliO) ~ c -\tt ~ J-J.-c .. + i+ctt4 ~

I+ - + c e- ~i

r:---1

1-'\I/ ~ - C - C I

II f

More than one substitution can occur on same molecule:hv CCit..t -+ ~ \ f C I( L{ ClJ-- ~ ~ ~ Cl $ )

A mixture of products (constitutional isomers) can occur when there is more than onecarbon in the molecule:C4H1o + 2 Cb hv Cy H?:; C / ~ + ~ ltC I C' ct C/

4

c1 c' ct c 1 c 1 \ 1 1c1 , , I c I L c-c.-c-c_ e-c-c-ei C (_;- c - c -c_. C - L -C-- . c- c- (_ - I \c-c..-c- , 1 ' I ct1 ct l' \ " . j ~ - c l \ c U I \ D ~ " D ~ : ; - dCl d' h\ . :1 13--o\lc\\\oro ) 1L\-c t t ~ \ b H ; 0"1 )1> t-cttcV\\ofO-tA.N


6/53

1. Fill in the table below for substitution reactions:

reactant(s)

b)

reactant(s)

+ 2 HBr

Type of reactionc:) 5 ct.bsfi-k\-{OUI

hv1/:,c '---- ~ / CHs -+ 1-lr

Iproduct(s)

Type of reactionc:) 5 QV:,siitu_hD t11 .

2. What products would be formed in the reaction between cyclopropane andchlorine gas in the presence of light?

~ c t + 4 C {Without light?

f\0 IX ~ ~ \ ' \ L Q . ~ ~ t ~ ~ W~ C U t & ~ 0 t L e r \ ~ m&lca..Ul { C l ~ ) ~ i l i a ~ ( R n _ G t \ ~ .

5


7/53

Textbook: Sect 1.2:Hydrocarbons p. 11-15 Sect 1.3: Reactions of Hydrocarbons p. 24-25Practice p. 151 Write the IUPAC names for the follow1ng hydrocarbons:a)CH3ICHs CH2I , I > 1; -,H 3C - C H - C H - C H -CH CH 2 - CH 3

t 1- I '-t ICH3 CH3

c) 2- tCH2-CH3I ) 6 1

H3C-CH -CH2-CH-CH2-CH CH 3:, 4 I ICH3 CH2 -CH2 -CH3

'i5 cr l ( )

2. Draw a structural dia ram for each of the followin h drocarbons:a) 3,3,5-trimethyloctane b) 4-ethyl-3,4-dimethylheptane

7

c) 2-methyl-4-isopropylnonane d) cyclobutane

D({ 1

6


8/53

7

Unsaturated Aliphatic HydrocarbonsUnsaturated hydrocarbons have double and triple bonds between adjacenthydrocarbons in the chain. The electron density of these double and triple bonds makethem a site of chemical reactivity. Interaction of light with the double bonds canproduce vivid colours:

CH3lycopene- red of tomato, paprika and watermelon

Nomenclature1. Alkenes, CnH2n. The double bond takes priority when numbering the hydrocarbon. Ifthere is more than one possible location for the double bond, then locator numbersmust be used.

H H H H H H'c==c/ " / " // ' /C=C, /H H /C=C,H H H /c"- ) " HH H H Brethene propene 3-bromopropene

H ~ = = C H - C H 2 - C H 3 H3C -CH ===CH - CH 3 H3C -CH 2 - CH = =CH - CH3

1-butene 2-butene 2-penteneDouble bonds are made with one sigma and one pi bond. Pi bonds are formed withunhybridized p-orbitals which have two lobes- one above and one below the sigmabond.

The two lobes of the p-orbitals overlapabove and below the C-C sigmabond.This forms a pi-bond that prevents thebond from rotating.C:[He] 1 1 1 1sp2 sp2 sp2 P

a bond a bond a bond :rt bond


9/53

Because the double bond cannot rotate, the geometry of the bond is locked in place.This causes the formation of geometric isomers:

trans-2-butene cis-2-buteneName these alkenes. The longest chain containing a double bond is the parent. Achain containing two double bonds ends with "diene".

l ~2.. l4;

3,3_d Yeth l j - i -bGlTel\eS f l \ ~ - t t -d - p n : ; ~ -- pe_(\\Q_ \\, !(

Br' 1 - -# )

5 - b f ' o m . o - ~ , 4--1\ .e rtos\ed( eO\.(>

2. Cycloalkenes, CnH2n-2. The double bond always takes Cl and C2. When there ismore than one double bond, number the ring to give them the lowest numbers.

8


10/53

3. Alkynes, CnH2n-2, remember the linear geometry for four atoms in a row

I 2.

I 2 ]H -C==C -CH 3

Chemical Reactions1 CombustionSC2H4 + 02 -

2. Addition: Here an entire molecule adds across the double bond, so there is only oneproduct. The electron density of a double or triple bond makes the bond vulnerableto attack by:a) halogens (F2,Cb,Br2,b): are very electronegative so they can attack with nocatalyst or light needed

Cl ClI IJ./--c-c-1+O ~ V L '-) Of\.J ~

?PGbu.LTr 1tl HC. I --- ( l Cl Cli lH-c -c -14( I+l 1-iC -Cl -7 i+- C.:_=._ --_ -J-1I Irl 1-\

-}

c_ \ -- etttv..-dcsc\ o ~ ~ l - e . C:: c_ b ~ ~ 11 wru1 ~ ~ \woCs t'J i'.v:tiLS

9


11/53

I,

-'),;!..

H

b) haloacids (HF,HCI,HBr,HI): two o n ~ , H+ and x-: the positive H+ ion is the oneattracted to the double bond, so 1t attacks first:' - /H-c + HCI t-t ClI I..,. ~ -C..__ C - I {/ \

H HI It-1 H

10

W oJ\v...d


12/53

When a molecule is asymmetric about d 11applies (the rich in hydrogen get richer h ~ ~ ~ ~ ~ ~ ~ ) ~ d , then Markovnikov's ruleCl 4

HsC" /H

I \- - - ~ . . . c h3- c - c_-1+c==c + HCIH/ \ H ' lH

0 [ \ ) ly}htD e_ie.droil c{GU.[I?o lasts t ~ ~ n ~ 3ni f - - t ~

C\- a ~ 01 . - . J ' ) D Q l ~ ' M (j;) '.+H;c- c - c -t+ + c ~ 8 -0

Cl ir-JI I

I ' - c- c -.}{1SL I )! Irt H rl d14 ~ l ) J \ S-ttA ---tko. mas.+ i-l~ '--14 QK-h t-1 . ~ t - I d ~


13/53

12c) water: not able to attack on its own, it needs an acid catalyst

H3C"' Hc===c// \H H

-I'0 X j 3til. (lj:ul\ 1t ~ V \~ ~ ~ e . bO'I\Cl'

::. 1'-

11- 0 ; 4{ lH c- c - c 1 + +3 I 1 tM H ~ ' c )

c a v n ~ + ~~ \ ~ l t - ~


14/53

13d) hydrogen: not able to attack on its own, needs a metal catalyst (Pt, Ni, Pd)HsC'\. H H )-4

c== c / i ; ./ + H2 metal H\ .. t-\; (_ -- c - C_ -H H i jH-H ~~

'0.- e1-oJ s Ll t'- f?a.c -'- - ~

l-i HH- - -

H 1-\ -PcN\'lS LDt- bOV\tD w t ~(\\ ~ - t t l \ S U I ~ C e c fu ; U ) ~ . C ) J G 2 . o \ , _ s-+4 ti ~ H d r ' U horJ .

. ~ t R _ ~ A A ffi. 1\LW ~ e d -to --trAQ. 1-( - -l-1 ,wd itsIt 0iJI\J bV'eaiCC ~ > ++( (- C _ ~ _ c - ~ - )

Fill in the blanks for the followin reactions:1. )ycl

lvLelCbproduct(s)

Type of Reaction Ac\d \hoV\


15/53

2.C) H+Type of Reaction P1dctin\ov1

3.

reactantType of Reaction

product(s)

Cl

Cl

14

t\J\a!'I(QUn t l Sl 'lk \ -e

Textbook: Section 1.2 Hydrocarbons p. 16-18, Section 1.3 Reactions of Hydrocarbons p.25-27 Practice p. 185. Write the IUPAC names for the compounds with the following structural diagrams:a) b)CH3 7cH3

t "l. ) ul )- (D IH ~ - c = = c -CH -CH-CH2ICH2-CHJ


16/53

15c) d)

e)

4 3

6 D t t I d" faws rue ura 1agrams or each f th f II de o ow1ng compoun s:a) 5-ethyl-2-methyl-2-heptene b) 1,3,5-hexanetriene2.. ~ L'1 ({_I .., -::::::---

c) 3,4-dimethylcyclohexene d) 1-butynelQ t 2. ~~-

e) 4-methyl-2-pentyne\ ~ c ;


17/53

Practice p. 271. What compounds will be produced in the followin addition reactions?

+ HBr

c)C H 2 C H ~ H 3I + H20

H3C'-...C/CH........_C?CH2H2 H

d) 0 +Ch

Ht c a t a l ~ s tJ

ItlHs C - c._ -IH~ - C ~ - k C 1 i 3tH2CH3

+-1 br---~ f I .-----. J-\3 C-C - c - CHz_ -CHs

I !It c 3

t"\ ct!t(DVV\ t (O\l N.JJ J


18/53

3. Draw structural diagrams to represent addition reactions to produce each of thefollowing compounds.a} 2,3-dichlorohexane

b) 2-bromobutane

C/i: : : > ~ GCl

B- - ) 1 ~M

M tr- !.{oV 1\ I kov ; 7


19/53

Aromatic HydrocarbonsHc

H C / ~ C HII IHC........_ ~ C Hc

Aromatic hydrocarbons are based onbenzene ring, C6H6.H

A benzene ring has a cyclohexane'skeleton'. Each C-C bond and each C-Hbond is as bond. So each C has threehybridized sp2 bonds it uses for singlebonds. The result is a planar (flat) ring.

H

H--=o;___ _......;o;;.__ H

_ . . . . . : o ~ - H

HEach C in the ring also has anunhybridzed p-orbital. The two lobes ofthe unhybridized p-orbital extend aboveand below the ring. These p-orbitals areused to make three p bonds above andbelow the si ma bonds of the rin .

The cyclohexane ring is unique inthat it puts the six ring carbons

H-- -- H close enough that their p-orbitals, n ~ are all able to overlap with eachU other.H-- o ~ ~ - - H

c

H

18


20/53

H He eHe / ~ e H .b '..........: H e ~ "'eHII I ~ ~ , . . . . I IIHe , .beH He=--.. eH

........ ~ /e eH H

A benzene ring is often drawn as acyclohexane ring with a circle in themiddle. The circle represents thedelocalized n bonds.Note the six Hs are not shown.

19Because of this the three n -bonds can keepshifting position. In fact the three n -bonds arecontinuously moving. You say that then -bonds ofbenzene are delocalized. This delocalized nbonding gives a great stability to the benzene ring-it is very much more stable than a simplecyclohexene ring, and much more stable than acyclohexene ring with three ordinary (not shifting)n bonds would be.

H

A diagram of a benzene ring might look likethe one above. Because then bond hastwo lobes, benzene forms two circles ofdelocalized n bonds- above and belowthe rin .

Nomenclature 1 Benzene as the parent

0benzene1,3-dimethylbenzenemeta-dimethylbenzenem-dimethylbenzene

methylbenzene(toluene)

1 4-dimethylbenzenepara-dimethylbenzenep-dimethylbenzene

1,2-dimethylbenzeneortho-dimethylbenzeneo-dimethylbenzene

1-ethyl-2-methyl benzeneo-ethylmethylbenzene


21/53

202. Benzene as a branch: When benzene is a branch, it is called a phenyl branch. It isnot iven any special status over other branches.

Br5-phenyl-2-heptene 3-bromo-2-methyl-4-phenylhexane

CH3 CH3

!- m c l \ : \ ~ \ - d. -!ll-\i'bOO\zel1 eD - fY\e\h 11)\+ro\JJ-eU\:4? IIJ N02 ' lr-.~ -M - t v \ ~ j l - l , > , s - - -m fltTrci/Jer t\

Cl

~ - c h \ c r o - d - - l i \ ~ ~ \ - & - - p V w _ v \ ~ \he\fun e.

o - r.Hn:rto Lu__en t> ~ ,'-4, ~ - - l - 1 ' ~ 1 \ i - r o - T o h l ~ V \ e(T.N.I .J


22/53

Chemical Reactions p. 28- 301 Combustionc6H6 + i o2 - {Q cod.._+ 3A2_o

d c . e _ l - \ ~ + 1S' o ,_ ~ t). c o ~ t ~ b\z. 0Br

2. AdditionBr

Addition cannot happen becauseof the strength of the delocalizedpi bonding.

3. Substitution can happen, but only with a catalyst:~ of a halogen

11 AICI3+ C b - - - - ~ ) 1 . -It

IM 1, , , , 0 , 6t.\.7e_ tlCjht! C\a >r f i \ U ~ 7 Cl i- f"i)C\t{ ,b) of an alkyl group (using an alkyl halide)

+

LJJ Cl Hc1

21


23/53

c) of a nitro group (using nitric acid)~ H

l + ~ c x l H H @ / N O ~I H2S04ff ' I+ ~ N 0 3 ff / 0 ....._H

H @ 1'\1.18 n-\ J) 1I (JH-003 - ) ~ J o d - . -run . 1\)oP-' tAi)) ~ H- i roN\ 01,'BI CL) t\0

Fill in the blanks for the followin reactions:1.

FeCb Cl

reactant(s)Type of reaction Q 5 Ltl)sti+u Ho l l

2.

@Jr Cr\:3C\b_CI FeCbreactant(s)

Type of reaction Q s l\ \:)sti+u. ho V\N02

3. e d. Hi'J03 H2S04reactant(s)

Type of reaction Q s lJ\ s ~ 1 u \io \

22

+ H;z_O-1'H-+ frum beff\2ll\e

oH- -RoM HNOs

+ 2 HCI

+ HCI

+ 2 H20N02


24/53

23Textbook: Section 1.2 Hydrocarbons p. 19-21, Section 1.3 Reactions of Hydrocarbons p.28-30Practice p.214. Draw a structural diagram for each of the followin hydrocarbons:a) 1,2,4-trimethylbenzene b) 1-ethyl-2-methylbenzene

0

c) 3-phenylpentane d) o-diethylbenzene

e) p-ethylmethylbenzene{@

)


25/53

'I

24Practice p. 304. Predict the product or products formed in each of the following reactions:a)

0 + Cb AICb ....product(s)b)~ N02 @ ; N O ~ ~ z _ O2S04 .... t-+~ HN03product(s)

5. Propose a reaction series that would produce 2-phenylbutane, starting with benzeneand 1-butene as reactants.Ac\d.\h"D

/ ]-\-c .-\- c

I -lI+ C l - h C ~ b

S lA.\os +LL\io

-t HCI ~ H- c (ItClIC - CHz_Crt3IH

Ytat"kov 1\ \


26/53

AlcoholsThe functional group is the hydroxyl group, -OH. The carbon that the hydroxyl group isattached to, C-OH, is called the carbanol carbon.Physical Properties

25

The hydroxyl group enables an alcohol to have hydrogen bonding. A small chainalcohol dissolves well in water. The R- group of an alcohol is a non-polar hydrocarbonchain. You need one hydroxyl group for every 5 carbons to enable a large alcohol todissolve in water.The hydrogen bonding of water gives it a higher boiling point than a comparablehydrocarbon.

NomenclatureAlcohols rank over alkenes and alkynes in nomenclature.

H3C -OH HC-C-OH3 H2rn : ~ \ O f e V ~ J \ D l

OH OHI !3C -HC -CH 3p v ~ J \ - J . - 0 1C s o ~ r o ~ ~ t o\cd\ol) c ~ clopropctf\ o\

OH

HC - HC - C - OH3 2 H2p r e ~ P v \ - l -o ICn-pi'DP/j l oJcd\Ol J

OH

OHpn-\ctn e-d 13- cHo IOH

1-/"i\ \ V \ ~ l c ~ c o P Q v ~ \ u l ) -l -( J - I l l ~ ' - ~ ic\j c\opev1\uncJ)


27/53

Chemical ReactivityThe position of the hydroxyl group determines some of its chemical reactivity.OH

OH IH3C -CH

2- 0 H I HC-C-CHH3C -CH -CH 3 3 I 3CH3

a primary alcohol a secondary alcohol a tertiary alcohol(a 1alcohol) (a 2 alcohol) (a 3 alcohol)

1. Combustion

2. Elimination: happens in 2 and 3 alcohols in the presence of concentrated acid,such as cone. H2S04 to form an alkene.)0 j c ~ ~ ~ y ~

HC. - c- c -hI ;H Hcone.H2SOyhe-tt ~

I, ~ - \ l T I - N \ H ~ O 4. Q + \ & - 0 1 ~ Oct:

~ - cI1-t

t-l- c_ :::::. c. _.,c \3 + r-h _ 0\ l/-t c r\;,

26


28/53

273. Condensation: an elimination reaction between two 1alcohols only to form an ether,this again uses concentrated acid as a catalyst. u.LJ CO(\ .( rT;) c ~ ~ C H 2 ' d - o l - \ - H z - > O ~ ~ C } - t ~ , C H z - C - 0 - C t - \ z . C t \ 3 + Hz_O

I IH H4 --- - 1-lI 1 ' I 8c H3 - c ~ 2 - ~ - c,O- +I + _f-@)- p C\-\z_[l-\3 -) CH)-CHz- C-@ -C\--\2_c )If - - - - H 'li + Hz. o

l t- tl\)1'(\ o.dd r 1 ' < \ . c es ()HOh tho h t u . - ~ oec;J'boCbr\t0.1 t.>r, 0'1\1 q \fAQ_4. Oxidation: uses an oxidizing agent such as K M n O ~ ~ h furns from purple to greento brown as it oxidizes a substance. Oxidizing agents can be written as [0].

+ [o] - ~ -+ ~ 2 0

~ 1? ca r-b0X Ltc a . _ c _ ~C C@ + [oJ -7 ( ~ - , - C -Ol-\~ r o t - ~ X A A ~ CUJ. p : w r - ~ t ~ Co]f'ffi.c-\i:UV\...- ~ y U , < ; W IfR__QC--ttCN\ 1 \ t (()'{\_fcl\ed 1 p r ~ U - C 1 2 L OJv\. ~ \ J . d & J l t ~ ~i ~ ~ ~ Co] , t'&JVV ~ n t e L ~ \ . c ~ iJJ crx & 1 ~ l-6-- n..! ) ~ Y:fJC ,(\ _,tc) -

~ ~ S f ( \ 'uJ u ~ Cm\pUcoe_d. ~ ~ r - - - e C ( d - \ ~- R ) ~ b k ~ WuJ0 :

I'") c d.- 3 tI& i-t + o


29/53

b} of a 2 alcoholOJ+I

C -is-- c.. - cH.>IcH "': J-1' t\Ua

28

-t C ji!e t-on .e

CQf'bo..r\cl tt CL!J ~ ~ ~ ' e N \ v ~ c : V v u t u . / V v V \ J~ \4JVl'V_ ~ ~ ~ t r ) ( d l ~ ~ ~ .J.h_rto MDrz ~ J x u w - Q H .

c) of a 3 alcohol0 ~iC K ~ - c - C + \ ~IC+t3

Reactions

+

Fill in the blanks for the following reactions involving alcohols:1.

OH H+

Type of reaction I: }

~ +l4zoIProduct(s}

~ l u ~ ~ ~


30/53

292.

OH

+ (0)

Product(s)Type of reaction c)cYX ( ru-n-c))!\_

3.

H+

reactant(s) Type of reaction c ) f f i ~ ~ U ~

4.

/-fz_O +H+

OH +

\ o ()lco1Jv;{s. Type of reaction c) CO{'diN\hcUtol)


31/53

5.

H+

reactant(s)Type of reaction c') ~ a.:\eM..

6.H +-b.

1-\3( "- I / C '\ 61-\-C C:i ( "+i + (0)OH H

reactant(s) Type of reaction c' ) C))


32/53

c)OH

b - e . \ ~ 2 E?l'\ ~ - I) 3-d 1'0 t( 3 - f\ ~ c \ \ " b ' X CJ pi"'!L not )

2 D t t I d" faw a s rue ura 1agram or:a) 3-methyl-1-butanol(3-methylbutan-1-ol)!+ 1-1 CN> 4I I I 111- c .- c - C - (_-ItI I0 ~ ~ 1-+

c) glycerol (propane-1,2,3-triol)

0 ~ 1-\ of.\I ) I1+- ~ - c.. - c-)-\--I 1 IH OH H

31

b) 1,2-propanediol(propane-1,2-diol)Of-\ H 1'-\-I I c - ~J-J-C- c .-I I lM ou I f

d) phenol (that is its IUPAC name)Of-\-@


33/53

3. Draw structural diagrams showing:a) an isomer of butanol that is a secondary alcohol0 ~I

- c -c . -C . . - c -1 I

b) all the pentanols that are isomers Oi-\01-\ , I r I 1I . - c - c - c ~ ,c -c -c -c ~ -, c -C I ' I I ' I

ort\ I \ \-C- c_~ C - c_- c_

\

Practice p. 424. Explain briefly why methanol has a higher boiling point than methane.J!l e_-\it\a A e t'il ethel lMIJ-t- c- 0 l {'-t

Lt t-s o f \ \ ~ IJoiVc 1---'6fS C\ft\d ~ - b ( ) r ( ~ ~5. Arrange the following compounds in order of increasing boiling point, and givereasons for your answer.a) butane b) 1-butanol (butan-1-ol)1" j \lowes+- ~ ~ ' B ~ ~ > f

S ~ \ o f't est cha( \ 5 0 '+ ~ t nH- bOMlY\OlL-- bFs on\y + 1--.bt-c;. -a

32


34/53

Practice p. 447. Alcohols can be made by addition reactions.a} Draw structural diagrams to represent the reaction:2-butene +water- 2-butanol (butan-2-ol}OH H

I l I

c c_ --::: c - c..- + Hz_O1 I 1 1 -c_- c . ~ c - (__t '8. Elimination reactions of alcohols are generally slow, and require an acid catalystand heating.a} Draw structural diagrams to represent the reaction:

6HI- c._-IHp i--lIc - c -

ll lH

1-propanol (propan-1-ol} - propene + waterCOif\_(_ f/ ~

, I I + 1\ Ju'c = - c_ - )-;- i t.-H/ JI f It

33

~ jp, o_ (Oi'l ( V \ ( l ~ ~ ~ I A C . U V ~ " l ~ ~ * t V v Lfuv'-- Q _ ~ t \-\L-0 -1)2r E ~ 9. Onlylb few of the simpler alcohols are used in combustion reactions. Alcoholgasoline mixtures, known as gasohol, are the most common examples. Write a

balanced chemical equation, using molecular formulas, for the completecombustion of the following alcohols:a} ethanolI \-c- c -ot-\


35/53

b) propanolI I ( 3c - c - c -01-f + Q-,

I I d. d

Practice p. 4510 b) What are the advantages and disadvantages of methanol as a fuel, overmore conventional gasoline or diesel fuels? (Google this)

~ c ' - ~ ~ m ~_ 0\.rlt\DJI!\{yt) - ~ - o \-\ 1 . O J \ ~ C Y K ~ ~ \ 6()

~ t ~ ~ C)d-. to ~ 0 ' f 0 '~ N & ~ tvv'\ LM ~ fttJvv\__ U ~ f--f.CCXI\ ~ \ ) l [ ' e _

-- ~ ~ ~ w \ - H V d - ~ ~ t f \ . D _ l.1 1-6 [A_/) 'Y\d)j__ ~ll;s 0 v ' v ~

- ~ ~ ~ ih ~- 1Jooclt ~ , t < ~ _ t-01'1\ , ~ ~ \-o Mill


36/53

EthersThe functional group is an ether linkage, -C-0-C-Physical PropertiesThe C-0-C gives a bent geometry. This creates a small area of polarity within anotherwise non-polar molecule.

35

The bent geometry also hinders ether molecules from getting close to each otherto form good intermolecular bonds. Therefore ethers have a low boiling point andevaporate easily.e.g. CH3CH2-0H: bp = 80C CH3-0-CH3: b.p. =-25CNomenclatureIn an ether, the larger Rgroup is named as the parent, and the smaller Rgroup isnamed as an ether branch. Ether Branches

~ 0H3C -0 H3C-H2C-O I ~methoxy ethoxy phenoxy

Br

0"-.--methoxyethane d-- b{C)YY\0- ~ - . e . ~ ( ) ) ( ~ ~ l:t (\ ~

l OH

0--o& PNL (\ o-x_0- -;- ~ p + ~ n t


37/53

Chemical Reactivity:Combustion: The high volatility (ability to evaporate) of ethers makes themdangerously flammable. As they mix with 02 in the air, the smallest staticspark can cause an entire room to burst into flame.

36

Other than combustion, ethers tend to be chemically stable. This makes them goodsolvents: Since they are fairly non-polar, (only the one oxygen of the ether linkagecontributes any polarity), they dissolve most organic compounds easily- and they don'treact with them. The small polarity of their one oxygen lets them dissolve some polarsubstances as well- and not react with them. But their small polarity is not enough toallow them to dissolve in water, so they can be used to extract non-polar substancesfrom water. They have no acidic hydrogens, so again they can dissolve substances thatwould react with an acid. Because of this, ethers are used as solvents in many reactions.

Textbook: Section 1.5 Alcohols and Ethers p. 45-48Practice p. 4611. Write IUPAC names for the following compounds:a) b)

Practice p. 48 12. Like many organic compounds, alcohols and ether undergo completecombustion reactions to produce carbon dioxide and water. Select onealcohol and one ether, and write structural diagrams for their completecombustion.

Ct-\.3 -(\-\z -0+\ + 30.:{ -) ) COa -t 3 t-\z.OC ~ : , - 0 - C ~ - s t 30d ---;:, o


38/53

Aldehydes and KetonesThe functional group is the carbonyl group.

Aldehydes have the carbonyl group at the endof a chain.Ketones have the carbonyl group within thechain.

Physical Properties

0II~ c , H0

II~ c - . . . . . . . / '

37

The oxygen is not bonded to a hydrogen, so neither aldehydes nor ketones canform a hydrogen bond with themselves. Because of this, both have lower boilingpoints than a comparable alcohol:

A ketone has a higher boiling point than a comparable aldehyde. You wouldthink the aldehyde would be more polar than the ketone and so have the higherbp.The carbonyl group is more polar than an ether linkage. So small ketones andaldehydes are soluble in water.

NomenclatureAldehydes rank over ketones (perhaps because aldehydes are more reactive)and both rank over alcohols, alkenes, alkynes and ethers.

Ketones

propanone

r ; - ~ ~ x 3 - L\-rk x ~ - 3 -0\.Q

butanone 4-hydroxybutan-2-one0 0A


39/53

38Aldehydes -locator numbers are not needed since the carbonyl is always C 10 ~ 0IHsC-CH

Brethanol 3-bromobutanal0" " ' - o ~ o 0 ~ ? ~I 5

~ - ~ ~ ~ a . Q $-\f\ t h ~ 1- L\ -ll'Xo PQniQ f

T these:a) b) I00

d) e) 00 ' 1 ~ 1

1- P - & ( \ ~ I ~ r o ~ r \ -J:Cf\e 3-b -\.e_V\ -1-oi\.0[ 1- phl\\j prtj:tm 1he]

0 ~OH3-hydroxybutanal

0 ~ 0o.JJ -rn ~ ~ p op:tl\e.d0J

c) w ~0

f) Cl

0

l _ch -I)3-d\metw XJd -p r ~ - 2 ~


40/53

Chemical Reactivity1. Combustion

2. OxidationAldehydes: have a carbonyl hydrogen which can leave as part of an oxidationreaction.

Ketones: no leaving H on carbonyl carbon

+ [0] -+-:.... f\o t-XI ~ ~ \ ~C ~ V } ~ + l3. Addition (Hydrogenation): Addition of H2 across the C=O double bond. Thisneeds a catalyst, heat and pressure.

Aldehydes: a primary alcohol is formed:catalyst

- - ~ - he-al pressure

0 - -- - t--\I; .C-- .. H1-t

0 l ~I

H3C., /Y--- Hc_ J-1H;)._

39


41/53

Ketones: a secondary alcohol is formed:

catalyst

heat pre.ssure0 --- ~I IH3 c c ----~ c _ . . . . . . . . . . \

-l-1..2 Cti.3Fill in the blanks for the reactions below:l.

reactant(s)

2.OH OH

+ [0]

Type of R e a c t i o n ~ t:n


42/53

413. t-k-c-o\-\

~ + [0 ] HC-:;:::::::.O~reactant(s)

Type of R e a c t i o n ~ 0 X'lc\O..t\0 VI

Textbook: Section 1.6 Aldehydes and Ketones p. 49-56Practice p. 511 D t t I d" f h f th f II daws rue ura 1agrams or eac o e o ow1ng compoun s:a) ethanol b) pentanal

0 0z . ~ > ~ tr 'ioJtbC - c t-\

c) hexan-2-one d) phenylmethanal (benzaldehyde)0 -'loIl ~ ( p @3. Write the IUPAC names for the following compounds:


43/53

c)

Practice p. 524. Write the IUPAC names for the following compounds:a) acetone b) formaldehyde c) acetaldehydepro}:0-no lf\ --e

DII(_/ '-c.-- -e..-1

42

5. Arrange the following compounds in increasing order of predicted boiling points andgive reasons for your answer.a) b) c)

f l ' \ l d d l ~( c t p ~ - ~ ~ )


44/53

43Practice p. 566. Draw structural diagrams and write IUPAC names to illustrate the controlled oxidationof the following alcohols. Is the product an aldehyde or a ketone?a) 2-pentanol

0

+ [o] -)b) 1-hexanol

~ ~ o H -r Co]-)7. Predict the relat ive solubility of the following compounds in water, listing thecompounds in increasing order of solubility. Give reasons for your answer.a) b) c)

~ L \ } _ \ v t e( s ~ \ \ cwJ)polo-r-

rv\rot M f u ~ ~{ A YY\_QJJ.. ' L D \ ~

( 1 - l ~ )f l M ~ h ~ t o _

( ~ ~ ~n ~ .. ))6tD- 0'- )


45/53

44SCH4U: Hydrocarbons Practice Sheet

1. Give the correct name for the followin molecules:1. 2.

l

3, 4.

s

5. 6.

7. 8.


46/53

9.

11.

13.

' - .2- fs-

&Lt-bu-\- ~ \-3-c c \ D p t > p ~ l -I) L\ -

- h e__-xMQd \Ql\e

I)- \ : ) u _ _ ~ \ -;A- 1 " \ e . t \ \ ~ l - ~ - p r o p ~ 1-1; s--

- Q > A . ~ n . Q d \ e v t e15.

17.

10.

12.

14.

16.

7- b1C5mt) -3- o c _ ~ M

, ),_ Io ;, )

'0ql- d l i Y \ e 1 i ~ I - ~ - f1 01\ eU\ .Q

18.

45


47/53

2. Reactions: Fill in the missing information:Fill in the missing information for each of the following:1.

~ + 1 2

2.+ HCI

3.

:Ihv ~ t-M-r- t t ~ I c o v l . ~ l)-.t ~ k o . t - ~ (J{\ ~ ~

Product(s)Type of Rx: 5 Q \ : ) ~ i \ - \ u _ n ' O i \

Conditionsnecessary for aRx Cl

Type of Rx: 0 . . ~ 0 - i t\V'\1\;Product(s)

~ + H 2 0Reactant(s) Conditions..,necessary for a

Rx

Type of Rx: o..._cUi:tbnProduct(s)

46


48/53

4.

+Reatant(s)

5.

Reactant(s)

Br2 ConditionsNecessary

1h br coot& ~ ~ ~ ~ u c t ( s )Type of Reaction: S Q ~ - t d u . \ - l t m

+ HCI1'\01\9-

Conditions..Necessary

Type of Reaction:00-dit\01\Product(s)

47


49/53

1. Nomenclaturea)

c)

e)

g)

Grade 12 Chemistry: Organic Practice Sheet 2

b)OH

d)OH

f)

h)0 OH

QOH

0

~0 ~

OH 0--

48


50/53

i)

k)

m)

Br

o)0 0,l X ) ,

'L

j)

I)

1- e ~ - 3-- r N L ~ ~ ~ 3 0 " ' - '3-eth i u l Q ~ Qn) .

0

p)0

49


51/53

2. Reactions .Fill in the boxes for the followln reactions:a)

Reactant(s)

b) Cl'@>oM + - \ o ~

Reactant(s)

c)0~

(R e a c t a n ~ ( s ~0 I : :ll : c -7 .-c._- 1-lL " I

necessary ~conditions

Type of Reaction:

H+necessary ..,.conditions

Type of Reaction:

necessary ..,.conditions

Product(s)

Cl ~~ O ~ + H , OProduct(s)

Product(s)Type of Reaction: C ( d . . d A , ~

50


52/53

d)

~ 0 + [0 ]Reactant(s)

e)

f\(5\'\Qnecessaryconditiont

Product(s)Type of Reaction:

l J X I d _ C l ~ ~

necessaryconditions ~OH

0 0

Reactant(s) Product(s)

f)0 +Reactant(s)

Type of Reaction: ()t


53/53

g)

Reactant(s)

AlCisnecessaryconditions ..,.

Type of Reaction:

+ HCI

Product(s)

5 Gtb0 1+u,_t-\Of\

52

3. Order the following substances from lowest to highest boiling point: pentan-2-one,pentane, pentan-1-ol, hexane.

p w m V \ ~ L ~ e m \ * ? I P.eNt1ruv\ -;) --o Y\ {) L peY\bM_-1-ola H-o-c -c-c -c-c~ c --e -c -c -c IIC-C-C -c-C. c__ -c -c -c -cLDFs ~ r QipoG_- cDp0U 1 - t ~ b a n ~G ~

O ' n ~ L\) "fS,0 1 \ ~

p1 alkanes to aldehydes and ketones

Documents