DATE 14, 2011 ATE PERFORMED : SEPTEMBER 14,
Synthesis of 1-Phenylazo-2-naphthol R.J. Bitare2, M.C. Endico1, & . . !r"e 2 Institute of Chemistry, Chemistry, University University of the Philippines, Philippines, Diliman, Diliman, Quezon Quezon City 1101 1101 Philippines Philippines 1
Department of Chemical Engineering, College of Engineering, & Department of Psychology, Psychology, College of !ocial !ciences an" Philosophy, University of the Philippines, Diliman, Quezon City, 1101 Philippines
#BS$R#C$
Synthesis of azo como!n"s can #e achie$e" $ia the %ocess of "iazotization an" s!#se&!ent azo co!'in() *n o%"e% to $e%ify this %eaction, 1+heny'azo+2+nahtho', common'y no-n as S!"an *, -as synthesize" $ia the %eaction of a heny'"iazoni!m ch'o%i"e so'!tion -ith a #asic .+ nahtho' so'!tion) The c%!"e %o"!ct o#taine" -as then s!#/ecte" to %ec%ysta''ization an" its me'tin( oint -as o#taine") *ts %oe%ty as an in(%ain "ye -as a'so eamine") Th%o!( Th%o!(h h the %esc% %esc%i#e i#e" " %oce" %oce"!%e !%es, s, a )2 )2 ee%i ee%imen menta' ta' yie'", yie'", %es!m %es!me" e" to #e !%e !%e 1+ o heny'azo+2+nahtho', heny'azo+2+nahtho', -as o#taine") The me'tin( %an(e o#taine" fo% the %o"!ct -as 3034 5, fa%+off f%om the theo%etica' $a'!e of 161 o5) Desite not #ein( as c'ose as theo%etica''y %e"icte", the occ!%%ence of the sai" %eaction is sti'' confi%me" #y the o#taine" ee%imenta' %es!'ts)
%ntrodction
Azo como!n"s a%e o%(anic como!n"s -hich #ea% the f!nctiona' (%o! R+787+R9 in -hich the hy"%oca%#ons can #e eithe% an a%y' o% a'y' they a%e fo%ma''y "efine" as "e%i$ati$es of "iaz "iazen enee ;"ii ;"iimi mi"e "e<, <, =787 =787=, =, -he% -he%ei ein n #oth #oth hy"% hy"%o( o(en enss a%e a%e s!#s s!#sti tit! t!te te" " #y hy"% hy"%oc oca% a%#o #on n >3? (%o!s) Azo Azo com como! o!n" n"ss a%e a%e ofte often n $i$i $i$i"' "'y y co'o%e", main'y "!e to thei% hi(h'y con/!(ate" st%! st%!ct ct!% !%e) e) Beca Beca! !se of this this %o %oe% e%ty ty,, azo azo como!n"s a%e !s!a''y !se" as "yes) One s!ch eam eam' 'ee is 1+h 1+heny eny'a 'azo zo+2 +2+n +na aht htho ho', ', mo%e mo%e common common'y 'y no-n no-n as S!"an S!"an *, an o%an(e o%an(e+%e +%e" " o-"e%e" s!#stance) *t -as %e$io!s'y !se" as "ye fo% teti'es an" as foo" co'o%in( #!t -as s!#se& s!#se&!en !ent'y t'y #anne" #anne" fo% s!ch s!ch !ses !ses "!e to its ca%cino(enicity)
Azo como!n"s a%e !s!a''y synthesize" th%o!(h "iazo"i!m co!'in( %eaction, a tye of e'ect%ohi'ic a%omatic s!#stit!tion) s!#stit!tion) *n o%"e% to synthesize an azo como!n", a%ene"iazo a%ene"iazoni!m ni!m sa't is %eacte" %eacte" -ith acti$ate" acti$ate" a%omatic %in(s 'ie heno's an" othe% amines) The amine comonent of the como!n" m!st #e 'es 'ess acti acti$ $ate" ate" the the co! co!''in( in( com comone onen nt) Mean-hi'e, the nit%o(en in the sa't se%$es as a #%i"(e #et-een the t-o t-o %in(s in the %eaction) %eaction) The The syn synthes thesis is of 1+h +heny eny'azo 'azo+2 +2++ nahtho' nahtho' !ti'izin( !ti'izin( ani'ine ani'ine an" .+nahtho .+nahtho'' is a t-o+ste %ocess in$o'$in( "iazotization an" azo co!'in( co!'in(,, as sho-n sho-n #y the fo''o-in( fo''o-in( %eaction %eaction >4? "ia(%am:
NH2
N
N a N O 2 / H C l/H 2 O
+
N Cl
-
OH
N N a O H / H 2O
N OH
'i(re 1. @ene%a' %eaction to synthesize 1+ heny'azo+2+nahtho' $ia azotization an" co!'in( %eaction
This ee%iment aims to synthesize 1+ heny'azo+2+nahtho' $ia the afo%ementione" %eaction)
E)peri*ental etail
Synthesis of 1+heny'azo+2+nahtho' is "i$i"e" into t-o ma/o% %oce"!%a' %eactions: the "iazotization %eaction an" the co!'in( %eaction) As s!ch, this ee%imenta' metho"o'o(y fo''o-s the same t%en" -ith the a""ition of in(%ain "yein( as an a'ication %oce"!%e) The%e a%e t-o main %ea%ations that -e%e "one "!%in( the co!%se of this ee%iment: 1< %ea%ation of the "iazoni!m sa't ;heny'"iazoni!m ch'o%i"e< so'!tion an" 2< %ea%ation of the .+nahtho' so'!tion) To %ea%e the "iazoni!m sa't so'!tion, 0)2 m ani'ine, 0)6 m -ate% an" 0) m concent%ate" hy"%och'o%ic aci" -e%e com#ine" in a 0+m E%'enmeye% f'as st%ict'y fo''o-in( the se&!ence of int%o"!ction as state" he%e) The so'!tion -as then s!#/ecte" to a "ec%ease in
teme%at!%e $ia an ice #ath to a#o!t 4 5) A co'" mit!%e -as %o"!ce" afte% 1+m of co'" "isti''e" -ate% -as com#ine" into the mit!%e) To this %es!'tin( mit!%e, 0)6 ( of 7a7O 2 c%ysta's -as (%a"!a''y a""e" -hi'e maintainin( the teme%at!%e #e'o- 5) A .+nahtho' so'!tion -as %ea%e" #y sim'y "isso'$in( 0)6 ( .+nahtho' in 4) m a&!eo!s 7aO= in a 0+m #eae%) As -ith the "iazoni!m so'!tion, this %ea%ation -as coo'e" "o-n an" maintaine" at a teme%at!%e of a#o!t 4 5) To %e+test the synthesis %eaction, in(%ain "yein( -as "one) Beca!se of the nat!%e of the S!"an+1 ;1+heny'azo+2+nahtho'< "ye, it "oesn9t %eact o% #on" -e'' -ith cotton fa#%ic #eca!se of the 'ac of f!nctiona' (%o!s in the fa#%ic) As a co!nte% metho" to this 'imitation, in(%ain "yein( -as "e$e'oe") *nstea" of %o"!cin( the "ye in"een"ent'y then a'yin( it to the fa#%ic, S!"an+1 is synthesize" insi"e the fa#%ic so that it -i'' #e t%ae" in the in"i$i"!a' fa#%ic comonents -he%e it -i'' #e fo%me") To "o this, a 2 #y 6 cm fa#%ic -as fi%st soae" in the co'" .+nahtho' so'!tion fo% a#o!t 2+6 min!tes) *t -as then %emo$e", atte" "%y -ith fi'te% ae%s an" imme%se" in the heny'"iazoni!m ch'o%i"e so'!tion) As a %es!'t, a %ominent %e"+o%an(e "ye fo%me" -ithin the fa#%ic) Afte% some mo%e min!tes, it -as %emo$e" f%om the so'!tion an" %inse" -e'' -ith %!nnin( -ate%) The %e"+o%an(e "ye %emaine" in the fa#%ic) Afte% the in(%ain "yein(, synthesis of S!"an+1 !sin( the com#ination of -hat %emaine" of the 2 %ea%ations -as set) Pheny'"iazoni!m ch'o%i"e so'!tion -as a""e" into the .+nahtho' so'!tion s'o-'y -hi'e sti%%in() The mit!%e -as sti'' maintaine" at a#o!t 4 5 fo% 1+ min!tes #efo%e fi'te%in( the %o"!ct an" -ashin( it -ith sma'' o%tions of co'" -ate%) This c%!"e %o"!ct -as %ec%ysta''ize"
!sin( minima' o%tions of hot ethano' in a steam #ath) The %es!'tin( %e" c%ysta's -e%e co''ecte", "%ie" an" -ei(he" a'on( a %e+-ei(he" fi'te% ae% to "ete%mine the o$e%+a'' yie'" in the synthesis %eaction)
+
NH2
NH3 H C l
Cl
Fina''y, the me'tin( oint of the %o"!ct -as "ete%mine" !sin( the common hot oi' imme%sion techni&!e)
+
N
-
N a N O 2 + H C l D i a z o t i z a t io n
OH
N -
Cl
Reslts and iscssions $a"le 1. Ee%imenta' Res!'ts
OH +
Cei(ht of S!"an * Theo%etica' ie'" Pe%cent ie'" Me'tin( Point
N
0)60 ( 0)4 ( )2 30+34 o5
The %e"+o%an(e azo "ye 1+heny'azo+2+ nahtho' -as o#taine" th%o!(h the %eaction of a "iazoni!m sa't inte%me"iate fo%me" f%om ani'ine -ith .+nahtho') 0)2 m of ani'ine an" 0)6 ( of .+nahtho' %o"!ce" 0)6 ( of 1+heny'azo+2+ nahtho' !on ee%imentation) The eecte" yie'" -as )4 ( o% 2)1 mmo') The%efo%e, the ee%imenta' yie'" is /!st of -hat co!'" ha$e #een %o"!ce" in a tota' an" e%fect synthesis) Of a $e%y consic!o!s note -o!'" #e the "isc%eancy of the ee%imenta''y+"ete%mine" me'tin( oint an" that of -hat -as theo%etica''y %oose") The ee%imente%s osit 2 ossi#'e so!%ces of e%%o% fo% this inconsistency: 1< a 'a%(e amo!nt of im!%ity in the fina' %o"!ct an" 2< a se'f+imose" misca'c!'ation "!%in( the act!a' me'tin( oint "ete%mination) The 'atte% may ha$e #een ca!se" #y an inefficient set+! -hi'e the fo%me% is #ein( att%i#!te" to otentia' 'ases "!%in( the fi't%ation hases) Fo% the a%tic!'a% metho" of synthesizin( 1+heny'azo+2+nahtho' e%fome" in the ee%iment, the %eaction mechanism is as fo''o-s:
N Cl
Cl
-
N H
-
C o u p l in g
- HC l
N N
N +
O
OH H
Diazoni!m co!'in( of a%omatic "iazoni!m ions no%ma''y haen on'y -ith acti$e s!#st%ates s!ch as amines an" heno's, #oth of -hich a%e st%on('y acti$atin( o%tho+a%a "i%ecto%s) 5onsi"e%in( the size of the attacin( secies ;in this a%omatic e'ect%ohi'ic s!#stit!tion<, s!#stit!tion occ!%s most'y in the a%a osition %e'ati$e to the acti$atin( (%o!) The a#i'ity of amines to (i$e o%tho an" a%a %o"!cts sho-s that e$en in aci"ic me"i!m, they a%e %eactin( in !n+ionize" fo%ms) =o-e$e%, at $e%y hi(h'y aci"ic concent%ations, no %eactions occ!% #eca!se the concent%ation of f%ee amines #ecomes too sma'') This is the %eason -hy
concent%ations of aci"ity a%e cont%o''e" in this ee%iment) =o-e$e%, this may a'so #e a so!%ce of e%%o% as the = 'e$e's -e%en9t monito%e" in the enti%e ee%iment) >?
N
N
H
N
H +
O
+
H
N OH
C
'i(re 2. Resonance st%!ct!%e of the attac of the "iazoni!m ion on ca%#on 1 of .+nahtho')
As sho-n in the fi(!%e a#o$e, the%e a%e 2 ossi#'e -ays of co!'in( -ith the .+nahtho') =o-e$e%, of these 2, the attac on ca%#on 1 is %efe%%e" #eca!se it fa$o%s %etainin( the %esonance+sta#i'ize" st%!ct!%e of the %in( an" sets the ositi$e cha%(e at a osition fa$o%a#'e to the enti%e synthesis) *n a""ition to o!% %o"!ct of inte%est, the%e a%e a'so 2 ossi#'e si"e %eactions that may %es!'t into 2 !n-ante" %o"!ct fo%mations) The fi%st one is the "i%ect s!#stit!tion of a n!c'eohi'e %esent in the inte%actin( so'!tion) The n!c'eohi'e may s!#stit!te the nit%o(en in the "iazoni!m sa't an" may fo%m othe% a%omatic como!n"s 'ie heno') The secon" one is the ossi#i'ity fo% a "ecomosition %eaction "!e to hei(htene" teme%at!%es) *n this case, the %o"!ct %e$e%ts #ac to ani'ine ;the %e$e%se %eaction of -hat is in Fi(!%e 1<) +
Nuc
N
N
+
acid
Nuc
'i(re +. Si"e %eaction -he%ein a n!c'eohi'ic s!#stit!tion in$o'$in( n!c'eohi'es s!ch as O= occ!%s)
P%actica' a'ications fo% the main %o"!ct of this synthesis %eaction -as sai" to #e in the fie'" of "yein() A "ye is consi"e%e" i"ea' if it is a#so%#e" #y the ta%(et fi#e%s efficient'y) Fo% this to haen, the "ye m!st #e e%fect'y #on"e" -ith the mate%ia' of the c'oth) The f!nctiona' (%o!s %esent in the "ye "ete%mine the st%en(th of a"hesion #et-een the "ye an" the teti'e) The #est "ye is the one -hich is caa#'e of #ein( a#so%#e" #y most fi#e%s) This "ye may ha$e a st%!ct!%e i"ea' fo% #on"in( -ith the mate%ia' of most'y !se" teti'es) As "isc!sse" ea%'ie%, S!"an 1 is not an efficient "ye #eca!se its a%tic'e sizes an" its %eacti$ities a%e not efficient fo% !se -ith ce%tain teti'es ;i)e) cotton<) This is a%tic!'a%'y "!e to !nmatche" st%!ct!%es that inhi#it "i%ect #on"in() 5onse&!ent'y, it -as c'assifie" as a cate(o%y 6 ca%cino(en >10? ) Meanin(, the s!#stance is otentia''y ha%mf!' an" may ca!se cance% in h!mans) Asi"e f%om 1+heny'azo+2+nahtho', -hich can #e %ea%e" #y !sin( ani'ine as the amine an" .+nahtho' as the co!'in( comonent, othe% "yes that can #e %ea%e" $ia a simi'a% fo%mat inc'!"e: O OH N N
1)
CH3 N CH3
,
O
-hich can #e %ea%e" #y !sin( OH
OH
O
NH2
OH
S
NH2
NH2
O
-hich can #e %ea%e" #y !sin( CH3
HO
N
S
O
O
CH3
as the amine an" comonent
as the amine an" as co!'in( H3C
N
O
O
CH3
as co!'in(
N
comonent) Conclsion H3C
The fina' %es!'ts sho- that the ee%iment -as a#'e to (i$e a )2 yie'" of a %o#a#'y sti'' im!%e sam'e of S!"an+1)
N CH3
2)
, NH2
-hich can #e %ea%e" #y !sin(
as
CH3 N CH3
the amine an" comonent an"
as co!'in(
6) OH
NH2HO
N OH
O
NH2
O
OH
S
O
N O
HO CH3
O
S O
OH
O S
N
N
O
Re(a%"'ess of the e%cent yie'", the fact that 1+heny'azo+2+nahtho' -as %o"!ce" an" ha" (i$en a ositi$e &!a'itati$e %es!'t ;%e"+ o%an(e "ye< $a'i"ates the theo%etica' %eaction of "iazotization an" its co%%eson"in( co!'in( %eaction) This, in co%%eson"ence, te''s !s that the %ima%y o#/ecti$e of this ee%iment to %o$e that an azo "ye synthesis eists $ia the sai" %eactions has #een satisfacto%i'y %eache")
S O
O
Desite a'' this, a com'ementa%y test ;me'tin( oint "ete%mination<, seem to #e a %o#'ematic iss!e in this ee%iment) 7ot that this on'y se$e%s an emi%ica''y teste" an" theo%ize" hysica' %oe%ty of S!"an 1 ;me'tin( oint<, #!t it a'so oens ! conce%ns a#o!t so!n" ee%imenta' techni&!es !se" #y the ee%imente%s "!%in( the co!%se of the ee%iment) Cith this at han", the ee%imente%s %ecommen" f!%the% in$esti(ation on mo%e efficient -ays of a tota' o%(anic synthesis fo% 1+ heny'azo+2+nahtho') G
References
>1? B%isto', T) S)+H) ;2002<) #zo Dyes) Ret%ie$e" Setem#e% 1, 2011, f%om 5hemist%y of Dyes: htt:II---)chm)#%is)ac)!I-e#%o/ects2002I%ic eIazo)htm >2? B%o-n, C) =), Foote, 5) S), *$e%son, B) ), J Ans'yn, E) K) ;200<) $rganic Chemistry ;th e")<) Hnite" States of Ame%ica: B%oosI5o'e 5en(a(e ea%nin()
QThe in"!ction of cytoch%ome P40 1A1 #y s!"an "yesQ) N) Biochem) Mo') Toico') 22 ;2<: 34)
#ppendi)
5a'c!'ations: 0.2 mL Aniline ×
1 cm
mL
>6? 5a%ey, F) A) ;1L<) $rganic Chemistry ;6%" e")<) HSA: Mc@%a-+=i'') 0.35 g β −naphthol ×
>4? 5hemist%y, P) S) ;n)")<) !ynthesis of the Dye !u"an I ) Ret%ie$e" Setem#e% 20, 2011, f%om htt:IIco!%ses)chem)s!)e"!Ichem6LICe# 20Syn0LIE61Syn0L)"f >? @eo%(ia, H) o) ;n)")<) Diazotization reactions ) Ret%ie$e" Setem#e% 1, 2011, f%om htt:IIasmehta)my-e#)!(a)e"!I"iazotization)htm ' >L? *nstit!te of 5hemist%y, Hni$e%sity of the Phi'iines, Di'iman) ;2003<) $rganic Chemistry %aoratory 'anual( !ezon 5ity: *nstit!te of 5hemist%y, HP Di'iman)
3
×
1.019 g
cm
3
×
1 molC 6 H 5 CH 2 OH 93.1265 g
1 mol β −naphthol 144.17
∴ Aniline is the limiting reagent
g
2.43 mmol β −n
=
)
Theo%etica' yie'": 2.19 mmol
Aniline×
2.19 mmol Sudan I
1 mmol Sudan I
×
1 mmol
Aniline
0.24828 g 1 mmol
2.19 mmol Sudan I
=
SudanI
0.54 g Sudan I
=
Act!a' ie'": >? Ma%ch, N) A"$ance" O%(anic 5hemist%y, Mc@%a-+=i'', 1L3, 63+400) >3? McM!%%y, N) E), O%(anic 5hemist%y ;th e")<) Sin(ao%e: Thomson ea%nin(, 2003, 41+4) >? Moh%i(, N)R), =ammon", 5) 7), Mo%%i'', T) 5), 7ece%s, D)5), Ee%imenta' O%(anic 5hemist%y) C)=) F%eeman, 13, 1+20, 23+ 21) >10? Refat 7)A), *#%ahim )S), Mo!stafa @)@), Saamoto )), *shiz!a M, F!/ita S) ;2003<)
=
0.30 g Sudan I ×
1 mol Sudan I 248.28
=
g
1.21 mmol Sudan I
Pe%cent ie'":
Yield
=
1.21 mmol Sudan I 2.19 mmol SudanI
55.2
=