Transcript
8/17/2019 9. Carboxylic Acids
1/43
Chapter 19: CarboxylicChapter 19: Carboxylic
AcidsAcids
CarboxyCarboxy group: -COOH, -COgroup: -COOH, -CO22H,H,
8/17/2019 9. Carboxylic Acids
2/43
Naming: Alkanoic AcidsNaming: Alkanoic AcidsIUPAC: Replace –IUPAC: Replace –ee of alkane name w!"of alkane name w!" –oc ac#–oc ac#
O
OH $-%e!"yl"exanoc ac#$-%e!"yl"exanoc ac#C&C&
Cyclc:Cyclc: Cycloalkanecarboxylc ac#'Cycloalkanecarboxylc ac#'
O
OH
Cyclo"exanecarboxylc ac#Cyclo"exanecarboxylc ac#
OHO
&-(ap"!"alenecarboxylc ac#&-(ap"!"alenecarboxylc ac#
C&, a' n cyclcC&, a' n cyclcal#e"y#e'al#e"y#e'
8/17/2019 9. Carboxylic Acids
3/43
Common (ame'Common (ame'
8/17/2019 9. Carboxylic Acids
4/43
Carboxylc ac#' !akeCarboxylc ac#' !ake prece#enceprece#ence o)er o!"er group':o)er o!"er group':
Inclu#e a' many func!on' a' po''ble n '!emInclu#e a' many func!on' a' po''ble n '!em
*+e!!er !"an $-ace!yl"ep!anoc ac#*+e!!er !"an $-ace!yl"ep!anoc ac#
8/17/2019 9. Carboxylic Acids
5/43
Physical PropertiesPhysical Properties
PlanarPlanar '!ruc!ure,'!ruc!ure,!rgonal!rgonal
carbonylcarbonylcarboncarbon
8/17/2019 9. Carboxylic Acids
6/43
"e carboxy group ' polar,"e carboxy group ' polar,
un#ergoe' "y#rogen bon#ng, an#un#ergoe' "y#rogen bon#ng, an#form' #mer':form' #mer':
.mer/a!on cau'e' rela!)ely.mer/a!on cau'e' rela!)ely"g" mel!ng an# bolng pon!'"g" mel!ng an# bolng pon!'
8/17/2019 9. Carboxylic Acids
7/43
8/17/2019 9. Carboxylic Acids
8/43
11H NMR Chemical ShitsH NMR Chemical Shits
HOC
O
H&0-&1 ppm&0-&1 ppm
2-23 ppm2-23 ppm cf al#e"y#e'cf al#e"y#e'an# ke!one'an# ke!one'
Al#e"y#e lkeAl#e"y#e lke
HC
O
OH
8/17/2019 9. Carboxylic Acids
9/43
8/17/2019 9. Carboxylic Acids
10/43
1!1!C NMR ChemicalC NMR Chemical
ShitsShits
(o! 4u!e(o! 4u!e
a' low fel#a' low fel#a' al#e"y#ea' al#e"y#eor ke!oneor ke!one
8/17/2019 9. Carboxylic Acids
11/43
"R Spectroscopy"R Spectroscopy
wo mpor!an! ban#':wo mpor!an! ban#':νν
O-HO-H 5 2300-1100 cm5 2300-1100 cm-&-&
,,νν
C5OC5O 5 &6&05 &6&0-&-&
8/17/2019 9. Carboxylic Acids
12/43
ResonanceResonance
7200 ppm7200 ppm
7&80 ppm7&80 ppm
8/17/2019 9. Carboxylic Acids
13/43
AcidityAcidity"e carboxy group ' rela!)ely ac#c:"e carboxy group ' rela!)ely ac#c:
Ace!a!eAce!a!e
Rea'on': & CarbonylRea'on': & Carbonyl carboncarbon ' n#uc!)ely '!rongly' n#uc!)ely '!rongly elec!ronelec!ronw!"#rawngw!"#rawng, 2, 2 Carboxyla!eCarboxyla!e on ' '!abl/e# byon ' '!abl/e# by re'onancere'onance
8/17/2019 9. Carboxylic Acids
14/43
Compare #Compare #
H
2-Propenyl *allyl2-Propenyl *allylCH2 H2C++HH 99
pp: : aa7 $07 $0
+99
8/17/2019 9. Carboxylic Acids
15/43
;lec!ron w!"#rawng;lec!ron w!"#rawng group'group'ncrea'encrea'e !"e ac#!y *#ecrea'e!"e ac#!y *#ecrea'e pp: :
aa::
C
8/17/2019 9. Carboxylic Acids
16/43
$asicity$asicity
Pro!ona!e# on !"ePro!ona!e# on !"e carbonyl oxygencarbonyl oxygen::
Allow' forAllow' for allylc re'onanceallylc re'onance
8/17/2019 9. Carboxylic Acids
17/43
&& Ox#a!onOx#a!on of prmary alco"ol' an# al#e"y#e'of prmary alco"ol' an# al#e"y#e'
>!" %nO>!" %nO$$? or CrO? or CrO11, H, H22O? or H(OO? or H(O1?1? or Hor H22OO2?2? or Cuor Cu2929, or Ag, or Ag99
Recall Cr*@I ox#a!on:Recall Cr*@I ox#a!on:
PreparationPreparation
In H2O: Hy#ra!e, w"c"ox#/e' !o ac#
8/17/2019 9. Carboxylic Acids
18/43
22 Carbona!onCarbona!on: Organome!allc: Organome!allcreagen!' an# carbon #ox#ereagen!' an# carbon #ox#e
;xample:;xample:
yn!"e!c '!ra!egy:yn!"e!c '!ra!egy: RHRH →→ RBRB →→ R%g+rR%g+r →→ RCORCO22HH
8/17/2019 9. Carboxylic Acids
19/43
11 (!rle "y#roly''(!rle "y#roly''
%ec"an'm:%ec"an'm:
au!omer/a!on
8/17/2019 9. Carboxylic Acids
20/43
COOH
Cl
C N
Cl
1.NaOH, H2O
2. H+, H2O
90%
Cyano"y#rn-"y#roly'':Cyano"y#rn-"y#roly'': -Hy#roxy ac#'-Hy#roxy ac#'
8/17/2019 9. Carboxylic Acids
21/43
ReactionsReactions
(ucleop"lc 'ub'!!u!on occur'(ucleop"lc 'ub'!!u!on occur'byby a##!on-elmna!ona##!on-elmna!on
Dea# !o carboxylc ac# #er)a!)e':Dea# !o carboxylc ac# #er)a!)e':
Eeneral:Eeneral::(u:(u
;;99
Dea)ngDea)ng
groupgroup
8/17/2019 9. Carboxylic Acids
22/43
;lmna!on
N%cleophilic S%bstit%tionN%cleophilic S%bstit%tion
by Addition& 'liminationby Addition& 'limination
e!ra"e#rale!ra"e#raln!erme#a!en!erme#a!e
A##!on
::
Po!en!al problem: Ac#!yPo!en!al problem: Ac#!y
Ac# or ba'e ca!aly/e#Ac# or ba'e ca!aly/e#
8/17/2019 9. Carboxylic Acids
23/43
$ase Cataly(ed Mechanism$ase Cataly(ed Mechanism
%u'! no! compe!e w!" :(u%u'! no! compe!e w!" :(u--
8/17/2019 9. Carboxylic Acids
24/43
Acid Cataly(ed MechanismAcid Cataly(ed Mechanism
8/17/2019 9. Carboxylic Acids
25/43
Synthesis o CarboxylicSynthesis o Carboxylic
Acid )eri*ati*esAcid )eri*ati*es
A+A+ AlkanoylAlkanoyl
HalidesHalides::R
C
O
OH
B5B5 Cl, +rCl, +r
+ -Cl + -OHRC
O
Cl
%ore%ore'!able'!able De''De'''!able'!ablePoorPoor(u(u +a# lea)ng+a# lea)nggroup, '!ronggroup, '!rongba'e, goo#ba'e, goo#(u(u
up"llup"ll
8/17/2019 9. Carboxylic Acids
26/43
"erefore u'e o!"er reagen!':"erefore u'e o!"er reagen!': OClOCl22, PCl, PCl33, P+r, P+r11
OClOCl22::
%ec"an'm:%ec"an'm:
8/17/2019 9. Carboxylic Acids
27/43
ame a' ROHame a' ROH RCl, excep! a##!on-elmna!onRCl, excep! a##!on-elmna!on
an# no! an# no! ((22
"en ! ' a##!on-elmna!on:"en ! ' a##!on-elmna!on:
8/17/2019 9. Carboxylic Acids
28/43
PClPCl33::
=0F=0F
O
OHPCl5
O
ClPCl3
OHCl+ ++
P+rP+r11::
8/17/2019 9. Carboxylic Acids
29/43
P+rP+r11 %ec"an'm:%ec"an'm:
&&
22
R
O
OH PBr2Br
R
O
OPBr2HBr++
R
O
OPBr2++ H+ Br -
R
OHOPBr2
R
O
Br+HOPBr2
Br
:
: :
: :
1
2
8/17/2019 9. Carboxylic Acids
30/43
$+$+
AnhydridesAnhydrides
Cyclc an"y#r#e': Gu'! "ea!, or OClCyclc an"y#r#e': Gu'! "ea!, or OCl22
8/17/2019 9. Carboxylic Acids
31/43
C+C+
'sters:'sters:Alco"ol' 9 carboxylc ac#', ca! mneral ac#, re)er'bleAlco"ol' 9 carboxylc ac#', ca! mneral ac#, re)er'ble
;xample:;xample:HH 7 0, 7 0, AA 7 0, 7 0, EE 7 0 7 0
Re)er'e:Re)er'e: ;'!er "y#roly'';'!er "y#roly'', #r)en by exce'' H, #r)en by exce'' H22O Can al'o beO Can al'o be
effec!e# by a4ueou' (aOH *C"ap!er J: RB 9 (aeffec!e# by a4ueou' (aOH *C"ap!er J: RB 9 (a9-9-OO22CRCR
;'!erHy#r;'!erHy#r
EallagEallag
8/17/2019 9. Carboxylic Acids
32/43
%ec"an'm%ec"an'm:: HH99 mneral ac#, eg, Hmneral ac#, eg, H22OO$$, HCl, procee#' n!ally, HCl, procee#' n!ally lkelke
ace!al/a!onace!al/a!on of al#e"y#e' an# ke!one'of al#e"y#e' an# ke!one'
(o!e: Carbonyl oxygen ' alway'(o!e: Carbonyl oxygen ' alway' more ba'cmore ba'c !"an!"an"y#roxy oxygen, becau'e of"y#roxy oxygen, becau'e of re'onancere'onance n !"en !"epro!ona!e# pro#uc!pro!ona!e# pro#uc!
8/17/2019 9. Carboxylic Acids
33/43
;'!er;'!er
8/17/2019 9. Carboxylic Acids
34/43
In!ramolecular e'!erfca!on:In!ramolecular e'!erfca!on: Dac!one'Dac!one'
;)en w!"ou! remo)ng !"e wa!er !"e e4ulbrum ';)en w!"ou! remo)ng !"e wa!er !"e e4ulbrum 'fa)orable becau'e of en!ropy *fa)orable becau'e of en!ropy *po'!)epo'!)e A' alway' n A' alway' nre)er'ble reac!on' *!"ermo#ynamc con!rol,re)er'ble reac!on' *!"ermo#ynamc con!rol,cycl/a!on ' be'! for f)e an# 'x membere# rng'cycl/a!on ' be'! for f)e an# 'x membere# rng'
8/17/2019 9. Carboxylic Acids
35/43
)+)+ AmidesAmides
"' me!"o# ' rarely u'e# Problem:
8/17/2019 9. Carboxylic Acids
36/43
%ec"an'm:%ec"an'm:
Hg"ly pHg"ly pHH #epen#en! profle >e '"all 'ee n#epen#en! profle >e '"all 'ee nC"ap!er 20 !"a! am#e forma!on ' be!!erC"ap!er 20 !"a! am#e forma!on ' be!!er
accompl'"e# by Kac!)a!onL of !"e carboxyaccompl'"e# by Kac!)a!onL of !"e carboxygroup, a' n alkanoyl "al#e' or an"y#r#e' orgroup, a' n alkanoyl "al#e' or an"y#r#e' ore)en e'!er'e)en e'!er'
8/17/2019 9. Carboxylic Acids
37/43
Cyclc am#e':Cyclc am#e': Im#e'Im#e' from #ocfrom #ocac#', orac#', or lac!am'lac!am' fom amno ac#'fom amno ac#'
Im#e forma!on:Im#e forma!on:
8/17/2019 9. Carboxylic Acids
38/43
Dac!am forma!on:Dac!am forma!on:
Penclln' are lac!am':Penclln' are lac!am':
N
S
OCOOH
HHRHN
OHR'
RMOH '!an#' for !ran'pep!#a'e, !"eRMOH '!an#' for !ran'pep!#a'e, !"een/yme nece''ary for all cell wallen/yme nece''ary for all cell wallcon'!ruc!on O'mo!c pre''ure n acon'!ruc!on O'mo!c pre''ure n acell ' enormou', &0-20 a!m Pencllncell ' enormou', &0-20 a!m Penclln
cau'e' l!erally an explo'oncau'e' l!erally an explo'on
8/17/2019 9. Carboxylic Acids
39/43
,ther Reactions o,ther Reactions o
Carboxylic AcidsCarboxylic Acids
&& Re#uc!onRe#uc!on by DAlHby DAlH$$
%ec"an'm complex,%ec"an'm complex,no! clear, po''bly )a:no! clear, po''bly )a: C
O
O
H
R
Al
Li
H:
2 H ll @ l" # l k R
8/17/2019 9. Carboxylic Acids
40/43
22 Hell-@ol"ar#-Neln'ky Reac!on:Hell-@ol"ar#-Neln'ky Reac!on:%ake'%ake' -bromocarboxylc ac#'-bromocarboxylc ac#'
P 9 +rP 9 +r22 P+rP+r11
Impor!an! func!onal/a!on? can be explo!e# !o acce''Impor!an! func!onal/a!on? can be explo!e# !o acce''-amno ac#' %ec"an'm ' remn'cen! of ac#-amno ac#' %ec"an'm ' remn'cen! of ac#
ca!aly/e# "alogena!on of al#e"y#e' an# ke!one'ca!aly/e# "alogena!on of al#e"y#e' an# ke!one'
Jako !ol"ar#Jako !ol"ar#$13&-1910'$13&-1910'
(kola ()li*ki *&8J&-&=31
Carl a* /o* H)ll*&8$=-&=2J
http://www.jergym.hiedu.cz/~canovm/mechanic/pravidl2/hell/z.htmhttp://www.jergym.hiedu.cz/~canovm/mechanic/pravidl2/hell/z.htm
8/17/2019 9. Carboxylic Acids
41/43
%ec"an'm:%ec"an'm:
A' n !"e ac# ca!aly/e# "alogena!on of al#e"y#e' an# ke!one',A' n !"e ac# ca!aly/e# "alogena!on of al#e"y#e' an# ke!one',!"' nee#'!"' nee#' enol/a!onenol/a!on of RCHof RCH22COOH Howe)er, !"e COOH groupCOOH Howe)er, !"e COOH group
' !oo '!able !o enol/e 'uffcen!ly, "ence ! re4ure'' !oo '!able !o enol/e 'uffcen!ly, "ence ! re4ure' ac!)a!onac!)a!on !o RCH!o RCH22C*O+rC*O+r
p: a 7 &J
8/17/2019 9. Carboxylic Acids
42/43
. ! l # " f ! 2 # 1. ! l # " f ! 2 # 1
8/17/2019 9. Carboxylic Acids
43/43
.e!ale# mec"an'm' of '!ep' 2 an# 1:.e!ale# mec"an'm' of '!ep' 2 an# 1:
top related