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Haloalk anes^ and
Haloarenes
Alkyl halicdes^ ano (^) Artyl halieles (^) are (^) foremeof yrreplacement
of byclnogen atom in aliphafic on orro mahe hyolro carbon
halogen atem s respec#vel
AnX
R-X
Alkyl holice)
ry haliole
ir Aregl on suhstilutref anyl
R Alkyl om suhshitstrol
alky
Xf, Cl,Br,
X F, Cl, Bn, 2
Monohalcgen Dercivaives
CH CI C2H^ Br
(Mehyl Chlbride^ )^ (Ethl^ bremiele)^ (Ehyl^
lockele) (Chlorro^ benzene)
Dihalogen DercivafAves
)Gemdihalboles
In there he^ two^ halogen otoms^ ane^ afHoched to (^) the (^) Same
carbon atom.
CH- -CH CI
(2.2-dichloroprropane
i) Vicina/ Dihalieles In (^) hese (^) molecules the oo In haleyen atoms ane (^) afache T Ciojacent carrbon aom
CH-CH
CH-CHGH C C U,2-dich lorro efhane) (,2-drchlorroprr0pane
ii) Treihalegen dereivatives
In these compounods thzee halogen afoms arce attaeheof
prcesent in one molet tule
-C/ B-G-Br -?
H Chlorroforem) Bromofercm). (lolofonm) Classikcaton bateot on the k)nof off Canbon atem
H R
R--XR-
R--x
R H H (Primang alky^ (Secon^ dan alky/ halade)
Tenhan
al kyl halts
haliole)
(3)
( 2°J ()
e hocls of
Paeparrafien .rrom Alcehols ytheth acthen of Phosphorus ha liole Phosphorrus halides^ rreacf^ with (^) al cohol to^ forenm^ alky halioles 3RCHOH+ PC 3 RCHC/+^ P (Alcohol) Alkyl^ halidle) 3CHCHOH + PC 3CHCHC/^ +^ HsP Ehanol) Ehayl^ Chloride) (^3) CH-H-OH t^ PBr, (^) drsny3Ch-ÇH- + (^) H Pg CH (^) CH (Isoprropyl alcohol (^) (1soprropyl krromiole)
GHC/+ POc, t+ Hc Efhyl chloniole) COH +PC- Efhanol)
y he achon ef thiony/ Chloriele
Alcohols react wilh thiony chlortide n presene of a
base o^ Forn^ Alky)^
Ch lortiele, RCHOH+SOCh CH,CHA/ + s0,+ HC/ Ethyl chl eride
CH,CH,OH + S0%
(Ehanol)
C using Luca's Reagent
2n Cl
Lucas ec^ age nt^ Con^ c.^ HCI^ A^ Anhyelcus^
Cn Cl
he
Alcohols rreact^ wih^ 2ucos^ reogenf^
fo forrn
respecively alky chlorriole
CH,CH,OH + HCI Zn^ Cla H,CHC/ + H
Ehanol (Ethyl^ chleoridle)
CH-OH +^ HCI^ TnCh^
CH
CHs
CH-C/ t H cHa
CHs
(2-chlorropr blane Isopropy/ alcohol)
CH ÇH
-OH + HC^ Cn^ Ch
cH Ch¢-c^ +H CH
Tentiny hu (Tertiong hubl chloricle)
aleohol)
- Preparrafiorn freom^
Alkene :
Alkyl halreles^ can^ be^ peepareof^ by^
he elechrophilrc
daddihon reachon ofalkene y the acfion of halrgen
acio.
-+HX
H
3. Rrom Si/verr^ salf^
of Hciel (Hms olieckerr^ reachon)Y
3.from
When sihven^ salF^ of aciol^ is^ reard^
wih Brr,alky/
hrromicle is Foremeof.
CHCoDAa+Bra-
Methayl brromide) (ilver acetak)
CHCHr+C0 + Br
CHCHCoDA2 + #n
Silvem prropionae) (Ethyl^ 6romicle)
4.Finke/sein's reachon ( locline Erchange
AIkyl chlorcictes or oromices en rreafing9 with potassiun
Enchang
loclide forem alkyl la=liede.
CHC + Nal aeianey GH? + NaC/
Ehyl chorcidte) Ethyl^ locdiele)
Haleacene
1.By Elechrophilc Subsfihuion Reacron: 1.A Ben2ene and ofherr arromaic hydrocarr hons rneact olirrect
with chlorene^ anl^ brromine^ af^ orelinany empera^
ture
1n (^) presen ce^ of^ Leois^ acids^ (Fe Cl,^ Fe^ Bn,.^ ALCI)^ fo^ fortm
Chlorto arrenes^ anod^ ruomoareneS.
C/0s20KO+HC3/0-32ok
BenTune) Ch^ lorrobenzene)
BrT
Br
(Bencene) Brromoben^ tene)
When fo/uene ls^ freeafeod^
with chlorcine^ in^ presen^ ce
beroue
When
oF (^) FeC wegef^ orho^ and^ parra
chlorcofoluene, beroue
olimecn9 9re/P.
of FeCl e^ ge
a reoup^ is^
orcfho ane^ poarco^ olimecing CH reCup^
CH
CHs
CH3 (^1) +2c 1o o2 (^) CI (O-chlrce toluene)
p-chlouo
toluene
Toluene)
CH (^) CH B (^) + 2HBT 10 +28Bn
Areyl fluorieles^
cannoF be^ prapareof by.dinec/^ Fluonin
hecause 2
s (^) veny (^) strton9 oHielabt^ ma^ anol^ makes
annof be controlleol,
he reachon^
violent and hence
Balt-Schiemann roackon
enene diatonium^ chlorcicde^ when^ trreatecf^
with fluorno-
boric (^) aid dliar on)um ferraFluorrohorrak (^) gefs precipitotd,
when heatrol^ ofecomjnoses to The dry terrafuorraborrate drd 7Ve fluorroben^ une.
o+ Bh +
Pluorro
3enaene lbenen Bence ne (^) diazonrum
odnatonium (^) feArraFluonoh orafe) chlortiede)
CnatfeTman Recacion
be preparud
in his^ reachon, chlorro^ anol^
brromoarenes can^ be^ prepareed
reatng oliatonium^ comjp^ ounds^
with a^ Fresh
pnenarne d
mntcurne dfF coppen powelerr anod HC/ orr H
ENC
ENC
C
Cu/HCI,O]+ N
o H^ o)+^ Na
bromo Ben zene
(1Benzene Chlero^ hen^ ene)^
bene ne diatonium diarenium (^) chlorrielek) chlorcide)
Raschig Prrocess
ChlorrohenTene can he^ obfainecl by
passing a^ minture
of benzene vap
ourts, air^ anod^ HC oven^ heafeof^ cuprric
chlorciede.
O 2 HCI^ +0,^ - Krom ai) (Chorrohenaune) (Benzene)
Prroperies
) Physical Stae
Ecept methyl ioclicle, ethyl bromicle anodehyl iooliole.
which arre liquicls aowerr memberrs celourlesS gases.
Fron aCis, all alkyl holides are Igurols
Frrom
Higherr memherts arre solrols.
(i) Selubili:
Alkyl haides^ ane^ polarr but (^) ane (^) insolukle in wakn. (^) Ths
is clue to^ therm (^) Inahili to (^) forrm Kyelrregen (^) bond
Alkyl halrdes ane solubleE (^) n orT qanc solvenfs,
ii) Melhng_points and boiing poin fs;
Haloalkanes have (^) highen meling poins^ ancl^ 6oiling (^) pom
as com parre o fo hyomo cartbons oF
comypanable mo/eralar
mass.
Mechan)sm of Reactiorn: (
heThe (^) nucleophilbc subsfubon^ reacrons^ of^ alkyl^ habeles
takes pla ce^ in^ any one^ of^ he^
fhree (^) ways
) Brakng^
of he^ olel^ Cc-X)^ hond^
Follorwead (^) k
b ono S,1 mecha nism)
he making of^
C-Nu
(2) Simultanecus^ making^ an^ hruekng^
of (^) honds
CSN2 mechanism
bd hreaking ) Makng^
of new^ hond^ follorwed^ by^
hreaking (3) Makima
of
of old^ b^ onds.^ (^ In arromahc^
ha ides
)Sn 7 (^ Unimolecularr^ Wacleop
hilic Subsitruion)^
mechanam
The Syl mechan^ ism^ of^ nucleophilic^
subshtuhon reach
Involve too 6ps
Sep-1:oremakon of Carhocahon)
In his^ skp. he^ halogen^
afom of^ alhy/ halicle (^) okepants
as leavinA group. leaolin9 fo^
he Fommaion^ of^ tarhoral
S/ou
cambocahon )
Step-2: AHach of nucleophile to the carbocafon)
The nucfeophile afacks rrom bofh siode of he rtesulm
The
carrbocafion leaoling^ fo^
he formakon two^ oifferent
tpes of^ prrooluef^
(racemic min^ fune
attack From Nu
Kroot sine mIw
Nu as
Attack Raemic Freom back iole
mintuze
wH Nu
he reafe of
rreachon of (^) alkyl haliele^ Follouoig Sn (^1) mech The Pollown
mec (^) hanism, depened upon^ he^ stabiliy^
of nfermecliafe
carhocaton. Greaferr^ he^ shabilit^ of^
camhocafion gruakre
16 he^ reachorn^
tate.
The oroder^ of.^ stabiu^
of carhocafion is^ as^ follows
The
H R
R >R-G R (^) H H^ H R Methy (Secend
Prchmary
Teniar
carbocaim)
Carbobocaiom)
carrbocabm) Ca7bocafom) Carbo coaHon)
The onederr^ of^ rea^ ctivih^
of (^) alkyl halides^ in^ S
The
reacion is
Tenhary habde^ Secendary^
habde (^) > frdmany halida
The ortolen ofF rreachwz oP alky^ halicles^ for^ dfront
halogen follcws^
he orderm as
R-2 R-/Bn^ R-C^
R-F
The rrates of Sy ceachon of all halsofes Follow he
orrolert
Primary olkyl^ haliole^ >^ Secondany^ alky/^
halide (^) Temkian
alhyl halde
Nucle (^) ophilhc (^) Substitufion rwacions (^) of (^) Haloalkanes.
() (^) Reachon wih (^) agueous alka When (^) an (^) alky/ halide (^5) rreafeo with (^) agueaus koH
/ e
soluron (^) orr with a, (^) w eaken base^ (most (^) hge0 /e,
Hg,0 +H0 2hg0H) halogen aom is rreplaceod by O
greup to fortm alcohol
RX + KOH- >ROH +KX
(alky/ haliee) (Alcohel)
CH-CH22 +*OHCat)^ CHC,^ OH^ +^ K?
Ehyl toelide) (Efhrganol)
CHCHL2 +lOH CHCH OH + 2
(Ety ledhde (Ethane^ )
CH-CH~CH3 + KOH Caa) C-CH-CH tKBr
Br OH
(Isopropyl bromiek) (loproeylalcohol)
Recncen wi soolium alkonlele (^) (
An alhl hahde on freament with mefal alkon'ede o
yie ields^
efher drd
R-X +R oNa R-0R + NaX
AIky/ halide^ )^ (Soolrum
alkonode)
(Eher)
-0-GH + Nal
(Diehyl eher)
GH-2 + GHoNa
Ehyl lcdiole)^ (^
Sochum ethonide) CH-0-GH+ Na?
(Ethylme^ hyl^ ethen)
CH2 + Na0GH
1ethyl helrta)
C)Reachien with^
Potassium cyaniade
AIky/
halioles orn^
treatment wit^
alcoholic solufroy^ of
he
olic soufon of
pofassum cyaniole^
gives
7he Cores/bencling^ alhyl^
eyon
R-CsN + KX
A/yl eyaniole)
es/ponclin2 alkyl yon
R-X+KCN
Alhyl haliole)
CHCSN+ KL
metoyl eyanide)
CH2 + KCN
(Mehyl odrde)
GB+ KCN -
Efiyl brormiede)
Ey yanide)
a) Reacfion with amnmonia
Alky/ halides^ on^ heafng^
with (^) ethanolic ammoniq
unolem pre esune yielo pti mony amines.
amines so forrmed reac Purther with ally
amines amof
PrcimaA
haliefes fortming seconolany ano fenrany
uaterrnay ammoniuM salf
2+HtN-H
(ehy
GNH t
Ethyl amine)
lodiole) G-y-¢ + H
H (Diethylamine)
GA-N-G +H
Triethyamine)
GH2 +e N
uaferhey ammoniUm (h) Reacion^ wifh Seolium hyolndsulpbjole
AIkyl halide when reakred with S0olium hyolrosulphide
if yields hioalcohels.
(Thiol)
RX Na SH.
4ky hahle) oodru
hyolrrosalphielk)
HA+NasH
Ehyl bo midt)
SH + NaBrr
Efhyl thioalcohol)
Reachon wih Soollum meraphde
Alky/ halicdes on reccfion^ with^ sooliunn^ mermcapfiole
yield hio ethe.
RX+ Na SR- RSR+ NaX
(Soclrum
merrcaphole)
Thioe fher)
CeA7 +GHS Na GH5G+ NaB
(Ethyl bromede ) (Sodvcan etlyl (Diéthern thioether) merrcaptiole)
)Recachon with Silver salfs of aciols
/hy haliodes on meecfron wth ethanolic solufio
oF si/err salt5 of carrhonyhC aciols, yielo he cores pon
esferrs
CH CH^ -oG^
g srr b
(3ilverr aafak) (Ehyl bromile) (Ethyl acefake)
K)Reachon with soediam alkynioles
When alkyl halicle^ is^ reeabeof^ wih^ sooliam^ alknieles
higherr alkyne^ is^ fortmecA. CH=CH+ Na NH-uiNa HCECNa+ NH
Acelylene )
(Soelrum acey liole)
CHh-C-2 + Na "C=cH CHC-cetH + Na?
Ehyl lochele) (^) 1ut-1 ne)
