GV: TH NGUYTCHNG III: AMIN AMINO AXIT - PROTEIN A.TM TT L THUYT:
Amin Aminoaxit Amin l hp cht hu c coi nh Aminoaxit l hp cht hu c
Khi nim c to nn khi thay th mt hay tp chc, phn t cha ng nhiu nguyn
t H trong phn t NH3 thi nhm amino -NH2 v nhm bng gc hidrocacbon
cacboxyl -COOH. TQ: RNH2( Bc 1) VD: CH3 NH2 CH3 NH CH3 CH3 N CH3 |
CH3 Tnh baz: CH3 NH2 +H2O [CH3NH3]+OH To mui R NH2 + HCl [R NH3]+Cl
C6H5 NH2 ( anilin ) TQ: H2N R COOH VD: H2N CH2 COOH (glyxin) CH3 C
H COOH | (alanin) NH2 Lng tnh p/ ha este p/ trng gng
CTPT
Peptit v Protein Peptit l hp cht cha t 2 50 gc amino axit lin kt
vi nhau bi cc lin kt peptit CO NH Protein l loi polipeptit cao phn
t c PTK t vi chc nghn n vi triu. p/ thy phn. p/ mu biure.
Ha tnh
khng tan
HCl
To mui [C6H5 NH3]+Cl -
Kim NaOH Ancol Br2/H2 Cu(OH)2 Trng ngng 1/ Ha tnh ca Amin: a)Tnh
baz:trng
To mui H2N - R- COOH + HCl ClH3N R COOH To mui H2N R COOH + NaOH
H2N RCOONa + H2O To este
To mui hoc thy phn khi un nng Thy phn khi un nng
v - aminoaxit tham d p/ trng ngng
To hp cht mu tm
R NH2 + H OH R NH3+ + OH +) Lc baz ca amin c nh gi bng hng s baz
Kb hoc pKb :+ [ RNH 3 ][ OH ] Kb = v pKb = -log Kb. [ RNH 2 ]
+) Anilin khng tan trong nc, khng lm i mu qu tm. +) Tc dng vi
axit: RNH2 + HCl RNH3Cl +) Cc mui amoni tc dng d dng vi kim: RNH3Cl
+ NaOH RNH2 + NaCl + H2O. b) So snh tnh baz ca cc amin: Tnh baz ca
amin ph thuc vo s linh ng ca cp electron t do trn nguyn t nit: +)
Nhm y e s lm tng linh ng ca cp electron t do (n) trn nguyn t N nn
tnh baz tng. +) Nhm ht e s lm gim s linh ng ca cp e t do trn nguyn
t N nn tnh baz gim. +) Khi c s lin hp n - ( nhm chc amin gn vo
cacbon mang ni ) th cp e t do trn nguyn t N cng km linh ng v tnh
baz gim. +) Tnh baz ca amin bc 3 cn ph thuc vo nhiu yu t khc trong
c nh hng hiu ng khng gian ca cc gc R. c) Phn ng th gc thm: +)
Halogen ha: Tng t phenol, anilin tc dng vi nc Br2 to thnh kt ta
trng 2,4,6tribrom anilin.
GV: TH NGUYT+) Sunfo ha: un nng anilin vi H2SO4 1800C s xy ra mt
chui phn ng m sn phm cui cng l axit sunfanilic.Cc amit ca axit
sunfanilic gi l sunfonamit hay sunfamit c tnh cht st trng khng
sinh, c dng nhiu lm thuc tr bnh. d) Phn ng vi axit nitr: +) iu ch
HNO2 : NaNO2 + H+ Na+ + HNO2. +) Phn ng ca amin vi HNO2: Amin bc 1
s c hin tng si bt kh: R-NH2 + HO NO R OH + N2 + H2O.
RAmin bc 2 s to hp cht nit z mu vng:
RN H + HO N = O
R'
R'
NN=O+
H2O. Amin bc 3 khng phn ng. 2/ Ha tnh ca Aminoaxit: a) Tnh cht
lng tnh: +) Phn ng vi axit mnh: HOOC- CH2NH2 + HCl HOOC CH2 NH3 +Cl
+) Phn ng vi baz mnh: NH2- CH2- COOH + NaOH H2N CH2 COOONa + H2O +)
Tnh axit- baz ca dung dch amino axit ( R(NH2)a(COOH)b )ph thuc vo
a,b. - Vi dung dch glyxin: NH2- CH2- COOH +H3N- CH2 COODung dch c
mi trng trung tnh( a = b = 1) nn qu tm khng i mu - Vi dung dch axit
glutamic ( a = 1, b= 2)lm qu tm chuyn thnh mu - Vi dung dch Lysin (
a=2, b =1)lm qu tm chuyn thnh mu xanh. b) Phn ng este ho ca nhm
-COOH
H 2 N -CH2 -COOH + C H OH 2 5
khHCl
2H
N -CH -COOC H + H O 2 5 2 2
c) Phn ng trng ngng - Cc axit-6-aminohexanoic v 7-aminoheptanoic
c phn ng trng ngng khi un nng to ra polime thuc loi poliamit.
n H-NH-[CH 2]5 CO-OH t3/ Ha tnh ca peptit v protein: a) Phn ng
thy phn:
( NH-[CH 2]5 CO ) n +n H 2O policaproamit (nilon-6)+ o
H ,t +) Vi peptit: H2N- C H-CO-NH- C H-COOH+H2O NH2 - C H-COOH +
NH2- C H-COO | | | | hay enzim
R1 R2 R1 R2 +) Vi protein: Trong mi trng axit hoc ba z, protein
b thy phn thnh cc aminoaxit. b) Phn ng mu biure Tc dng vi Cu(OH)2
cho hp cht phc mu tm . a s cc aminoaxit trong thin nhin l
-aminoaxit. Sau y l s liu lin quan n 15 aminoaxit thng gp trong cu
trc ca protein: CNG THC A. Axit monoaminomonocacboxylic 1/ C H2
COOH | NH2 2/ CH3 C H - COOH | NH2 TN GI Glyxin M= 75 Alanin M= 89
Valin VIT TT Gly Ala Val TAN 25,5 16,6 6,8 pHI 5,97 6,00 5,96
GV: TH NGUYT3/ CH3 C H C H COOH | | CH3 CH3 NH2 NH2 4/ CH3 C H
CH2 C H COOH | | 5/ CH3 CH2 C H C H COOH | | CH3 NH2 B. Axit
iaminomonocacboxylic 6/ C H2 CH2 CH2 CH2 C H COOH | | NH2 NH2 C.
Axit monoaminoicacboxylic 7/ HOOC CH2 C H COOH | NH2 8/ HOOC CH2
CH2 C H COOH | NH2 9/ H2N C CH2 C H COOH || | O NH2 10/ H2N C CH2
CH2 C H COOH || | O NH2 D. Aminoaxit cha nhm OH , -SH, -SR 11/ HO
CH2 C H - COOH | NH2 12/ CH3 C H C H COOH | | OH NH2 NH2 14/ CH3S
CH2 CH2 C H COOH | NH2 E. Aminoaxit cha vng thm 15/ C6H5 CH2 C H
COOH | NH2 13/ HS CH2 C H COOH | M= 117 Leuxin M= 131 Iso leuxin M=
131 Lysin M= 146 Axit aspactic M= 133 Axit glutamic M= 147
Asparagin M= 132 Glutamin M= 146 Serin M= 105 Threonin M= 119
Xistein M= 121 Methionin M= 149 Phenylalanin M= 165 Leu Ile Lys 2,4
2,1 Tt 5,98 6,00 9,74
Asp Glu Asn Gln Ser Thr Cys Met Phe
0,5 0,7 2,5 3,6 4,3 20,5 Tt 3,3 2,7
2,77 3,22 5,4 5,7 5,68 5,60 5,10 5,74 5,48
GV: TH NGUYT
B.CC DNG BI TP: 1.Xc nh CTPT ca hp cht cha Nit da vo phn ng chy:
y z y t CxHyOzNt + ( x + ) O2 x CO2 + H2O + N2. 4 2 2 2 V d 1: t
chy hon ton hn hp hai amin no, n chc, mch h l ng ng lin tip thu c
2,24 lt kh CO2 ( ktc) v 3,6 gam H2O. CTPT ca hai amin l: A. CH3NH2
v C2H5NH2. B. C2H5NH2 v C3H7NH2. C. C3H7NH2 v C4H9NH2. D. C4H9NH2 v
C5H11NH2. HD: CTPTTQ ca amin no, n chc, mch h l CnH2n+3N. nC(hh) =
nC(CO2) = 2,24/22,4 = 0,1 (mol); nH(hh) = 2nH(H2O) = 2.3,6/18 = 0,4
nC : nH =1:4
Chn p n A. 2. Xc nh CTCT ca amin, ng phn amin: V d 2: Cho 10 gam
amin n chc X phn ng hon ton vi HCl (d), thu c 15 gam mui. S ng phn
cu to ca X l: A.8. B.7. C.5. D.4. ( Trch TSH A 2009 ) HD: Phn ng: R
NH2 + HCl [R-NH3]+Cl - . S mol n amin = nHCl = (15 10)/ 36,5 m amin
= ( R + 16)/ 7,3 = 10 R = 57 R l C4H9 - . Cc ng phn amin ca X l:
CH3CH2CH2CH2NH2; CH3CH(CH3)CH2NH2; (CH3)3 C(NH2);CH3CH2CH(NH2)CH3;
CH3CH2CH2NHCH3;CH3CH2NHCH2CH3;(CH3)2 CH(NH)CH3; CH3CH2N(CH3)2; C 8
ng phn. Chn p n A. Ch : Khi vit ng phn amin nn vit t ng phn bc 1(
R-NH2), n bc 2(R-NH-R), bc 3(R-N-R). | R 3. Xc nh cng thc
aminoaxit: V d 3: Cho 1 mol aminoaxit X phn ng vi dung dch HCl (d),
thu c m1 gam mui Y. Cng 1 mol aminoaxit X phn ng vi dung dch NaOH
(d), thu c m2 gam mui Z. Bit m2 m1 = 7,5. Cng thc phn t ca X l: A.
C4H10O2N. B. C5H9O4N. C. C4H8O4N2. D. C5H11O2N. ( Trch TSH A 2009 )
HD: (H2N)xR(COOH)y + x HCl (ClH3N)xR(COOH)y; (H2N)xR(COOH)y +y NaOH
(H2N)xR(COONa)y + y H2O. Theo bi ra v theo cc phn ng ta c: m2 m1 =
23 y 36,5x y = 7,5 44y = 73x +15. Ch c x =1; y = 2 l ph hp vi cc kt
qu trong p n. Chn p n B. Ch : Nu y l bi ton t lun th s c v s p n v
c v s cp x,y tha mn, mt khc mi cp x, y li tng ng vi gc R ty . V d
4: Cho 0,02 mol aminoaxit X tc dng va vi 200 ml dung dch HCl 0,1M
thu c 3,67 gam mui khan. Mt khc 0,02 mol X tc tc dng va vi 40 gam
dung dch NaOH 4%. Cng thc ca X l: A. H2NC2H3(COOH)2. B.
H2NC3H5(COOH)2. C. (H2N)2C3H5COOH. D. H2NC3H6COOH. ( Trch TSH B
2009 ) HD: (H2N)xR(COOH)y + x HCl (ClH3N)xR(COOH)y; (H2N)xR(COOH)y
+y NaOH (H2N)xR(COONa)y + y H2O. Ta c: nHCl = 0,1.200.10 -3 = 0,02
(mol) = nX; nNaOH = 40.4%/40 = 0,04 (mol) = 2nx x =1; y = 2. mMui =
0,02( R + 52,5 + 2.45) = 3,67 R = 41 R l C3H5. Chn p n B.
n =1/4 2 n +3
n = 1,5
2 amin l: CH3NH2 v C2H5NH2.
GV: TH NGUYT4. Vit cng thc cu to cc ng phn Peptit v protein; V d
5: S ipeptit ti a c th to ra t mt hn hp gm alanin v glyxin l: A. 3.
B. 1. C.2. D. 4. ( Trch TSH B 2009 ) HD: Gly Ala v Ala Gly l hai
cht khc nhau. H2NCH2CONHCH2COOH (Gly Gly); H2NCH2CONHCH(CH3)COOH (
Gly Ala); H2NCH(CH3)CONHCH(CH3) COOH; H2NCH(CH3)CONHCH2COOH ( Ala
Gly); Chn p n D. 5. Bi tp tng hp: V d 6: Hn hp X gm 1 mol aminoaxit
no, mch h v 1 mol amin no, mch h. X c kh nng phn ng ti a vi 2 mol
HCl hoc 2 mol NaOH. t chy hon ton X thu c 6 mol CO2, x mol H2O v y
mol N2. Cc gi tr x, y tng ng l A. 7 v 1,0. B. 8 v 1,5. C. 8 v 1,0.
D. 7 v 1,5. ( Trch TSH A 2010 ) HD: aminoaxit l CmH2m -1O4N, amin l
CnH2n+3N 2m 1 1 O Phn ng chy: CmH2m -1O4N + 2 m CO2 + H2O + N2 2 2
2n + 3 1 O CnH2n+3N + 2 nCO2 + H2O + N2 2 2 S mol CO2 l : n+m =6
nH2O = n + m+ 1 = 7. S mol N2 = 1. Chn p n A. V d 7: t chy hon ton
V lt hi mt amin X bng mt lng oxi va to ra 8V lt hn hp gm kh
cacbonic, kh nit v hi nc (cc th tch kh v hi u o cng iu kin). Amin X
tc dng vi axit nitr nhit thng, gii phng kh nit. Cht X l A.
CH3-CH2-CH2-NH2. B. CH2=CH-CH2-NH2. C. CH3-CH2-NH-CH3. D.
CH2=CH-NH-CH3. ( Trch TSH A 2010 ) HD: L amin bc 1: R NH2 + HO NO R
OH + N2 + H2O. Chn p n A. V d 8: Hn hp X gm alanin v axit glutamic.
Cho m gam X tc dng hon ton vi dung dch NaOH (d), thu c dung dch Y
cha (m+30,8) gam mui. Mt khc, nu cho m gam X tc dng hon ton vi dung
dch HCl, thu c dung dch Z cha (m+36,5) gam mui. Gi tr ca m l A.
171,0. B. 165,6. C. 123,8. D. 112,2. ( Trch TSH B 2010 ) HD: S dng
phng php tng gim khi lng. m gam X + HCl (m+36,5) gam mui. Do : nX =
nHCl = 1 mol. CH3 CH(NH2)- COOH + NaOH CH3 CH(NH2)- COONa + H2O
mol: x x C3H7N (COOH)2 + 2 NaOH C3H7N (COONa)2 + 2 H2O. mol: y
y
x+ y = 1 Ta c h: x , 2 2 + 4 4y = 3 08Chn p n D.
x = 0,6 . Vy m = 0,6.89 + 0,4. 147 = 112,2(g). y = 0,4
GV: TH NGUYT
C. CU HI V BI TP TRC NGHIM T GII 1 ( Dng cho kim tra 45 pht): 1.
Nguyn nhn gy ra tnh baz ca amin l: A. do amin d tan trong nc. B. do
nguyn t N cn cp electron t do. C. do phn t amin b phn cc. D. do
amin c kh nng tc dng vi axit. 2. Trong cc cht: CH3CH2NH2; (CH3)2NH;
(CH3)3N v NH3. Cht c tnh baz mnh nht l: A. NH3. B. (CH3)3N. C.
(CH3)2NH. D. CH3CH2NH2. 3. Trong cc cht: CH3NH2; C2H5NH2; (CH3)2NH;
C6H5NH2.Cht c tnh baz mnh nht l: A. CH3NH2. B. C2H5NH2. C.
(CH3)2NH. D. C6H5NH2. 4. tch ring hn hp kh CH4 v CH3NH2 c th dng
dung dch: A. HCl. B. HNO3. C. HCl v NaOH. D. NaOH v Br2. 5. Pht biu
no sau y khng ng? A. Anilin tc dng c vi HBr v trn N cn c i electron
t do. B. Anilin c tnh baz yu hn NH3 v nh hng ht e ca nhn thm ln nhm
chc NH2. C. Anilin tc dng c vi dung dch Br2 v c tnh baz. D. Anilin
khng lm i mu giy qu tm m. 6. Tn gi ca aminoaxit c cng thc cu to CH3
CH(NH2) COOH l: A. axit - aminopropionic. B. axit - aminoaxetic. C.
axit - aminopropionic. D. axit - aminoaxetic. 7. Trong cc hp cht
sau, hp cht no khng lng tnh? A. Amino axetat. B. Lizin. C. Phenol.
D. Alanin. 8. S ng phn aminoaxit ca C4H9O2N l: A. 3. B. 4. C. 5. D.
6. 9. S ng phn cu to c cng thc phn t C4H11N l: A. 5. B. 6. C. 7. D.
8. 10. Dung dch glixin ( axit amino axetic) c mi trng: A. axit. B.
baz. C. trung tnh. D. khng xc nh. 11. Cht X c cng thc phn t
C3H7O2N. X c th tc dng vi NaOH, HCl v lm mt mu dung dch brom. Cng
thc cu to ca X l: A. CH2=CHCOONH4. B. H2NCH2CH2COOH. C.
CH3CH(NH2)COOH. D. CH3CH2CH2NO2. 12. Khng nh no sau y khng ng? A.
Cc amin u kt hp vi prpton. B. Tnh baz ca cc amin u mnh hn NH3. C.
CTTQ ca amin no, mch h l CnH2n+2+kNk.D. Metylamin c tnh baz mnh hn
anilin. 13. Cho (CH3)2NH vo nc, lc nh, sau yn th c: A. hn hp c nh
sa. B. hai lp cht lng khng tan vo nhau. C. dung dch trong sut ng
nht. D. cc ht kt tinh khng mu lng xung y. 14. Cp ancol v amin no
sau y cng bc? A. (CH3)2CHOH v (CH3)2CHNH2. B.(CH3)3COH v
(CH3)3CNH2. C. C6H5CH(OH)CH3 v C6H5NHCH3. D. C6H5CH2OH v (C6H5)2NH.
15. Phn ng no di y khng th hin tnh baz ca amin? A. CH3NH2 + H2O
CH3NH3+ + OH -. B. Fe3++ 3CH3NH2+ 3H2O Fe(OH)3 +3CH3NH3+. C. CH3NH2
+ HNO2 CH3OH + N2 + H2O. D. C6H5NH2 + HCl C6H5NH3Cl. 16. Cho s phn
ng: X C6H6 Y anilin. X v Y tng ng l: A. C2H2 v C6H5NO2. B. C2H2 v
C6H5-CH3 C.xiclohecxan v C6H5-CH3. D. CH4 v C6H5NO2. 17. phn bit 3
dung dch H2NCH2COOH, CH3COOH v C2H5NH2 ch cn dng mt thuc th l: A.
Na kim loi. B. dung dch NaOH. C. qu tm. D. dung dch HCl. 18. Pht
biu no sau y l ng?
GV: TH NGUYTA. Anilin tc dng vi axit nitr khi un nng thu c mui
iazoni. B. Benzen lm mt mu nc brom nhit thng. C. Etylamin phn ng vi
axit nitr nhit thng, sinh ra bt kh. D. Cc ancol a chc u phn ng vi
Cu(OH)2 to dung dch mu xanh lam. ( Trch TSH A 2009 ) 19. Thuc th c
dng phn bit Gly Ala Gly vi Gly Ala l: A. Cu(OH)2 trong mi trng kim.
B. dung dch NaCl. C. dung dch HCl. D. dung dch NaOH. ( Trch TSH A
2009 ) 20. Dy gm cc cht v thuc u c th gy nghin cho con ngi l: A.
penixilin, paradol, cocain. B. heroin, seduxen, erythromixin. C.
cocain, seduxen, cafein. D. ampixilin, erythromixin, cafein. ( Trch
TSH A 2009 ) 21. Ngi ta iu ch anilin bng s sau: 4 ) Benzen + HNO 3c
( H 2 SO Nitrobenzen Fe + HCl ( Anilin. t ) Bit hiu sut giai on to
thnh nitrobenzen t 60% v hiu sut giai on to thnh anilin t 50%. Khi
lng anilin thu c khi iu ch t 156 gam benzen l: A. 186,0 gam. B.
55,8 gam. C. 93,0 gam. D. 111,6 gam. ( Trch TSH B 2009 ) 22. Hp cht
X mch h c cng thc phn t l C4H9NO2. Cho 10,3 gam X phn ng va vi dung
dch NaOH sinh ra mt cht kh Y v dung dch Z. Kh Y nng hn khng kh , lm
giy qu tm m chuyn mu xanh. Dung dch Z c kh nng lm mt mu nc brom. C
cn dung dch Z thu c m gam mui khan. Gi tr ca m l: A. 8,2. B. 10,8.
C. 9,4. D. 9,6. ( Trch TSH A 2009 ) 23. Cht X ( cha C,H,O,N) c thnh
phn % theo khi lng cc nguyn t C,H,O ln lt l 40,45%;7,86%; 35,96%. X
tc dng vi NaOH v vi HCl, X c ngun gc t thin nhin v MX
