Pho Hong Ngoai Ir7

7/28/2019 Pho Hong Ngoai Ir7

1/88

1

Chng1.PH HNG NGOIInfrared (IR) spectroscopy


2/88

2


3/88

3


4/88

4


5/88

5


6/88

6

Thng thng th nvcabc sng csdng trong phhngngoi l m ( 1 m = 10- 4 cm) v thay cho tns (Hz),

ngi ta sdngnv l s sng:


7/88

7


8/88

8


9/88

9


10/88

10


11/88

11

Vng bc x hng ngoi (IR) l mt vng ph bc x in t

rng nm gia vng trng thy v vng vi ba; vng ny c

th chia thnh 3 vng nh:- Near-IR 400-10 cm-1 (1000- 25 m)

- Mid-IR 4000 - 400 cm-1 (25- 2,5m)

- Far-IR 14000- 4000 cm-1 (2,50,8m)

Phng php phn tch ph hng ngoi ni y l vng

ph nm trong vng c s sng 4000 - 400 cm-1.

Vng ny cung cp cho ta nhng thng tin quan trng v ccdao ng ca cc phn t do l cc thng tin v cu trc

ca cc phn t


12/88

12

c th hp th bc x hng ngoi, phn t

phi p ng cc yu cu sau:

- di sng chnh xc cabcx: mt phn thpthbcxhngngoichkhi no tns dao ng

t nhin camtphn phn t(tc l cc nguyn thay cc nhm nguyn tto thnh phn t)cngl tnscabcxti.

-Mt phn tchhpthbcxhngngoi khi noshp th gy nn sbin thin momen lngccca chng.


13/88

13


14/88

14


15/88

15

Tng quan gia ph dao ng vcu trc phn tCc nhm chc, nhm nguyn t v lin kt trong phn

t c cc mphhpthhngngoictrng khc

nhau .


16/88

16

Mc d phng php ph dao ng l mt trongnhngphng php huhiunht xc nhcc cht v nh tnh cng nh nh lng,cngdngrng ri trong nghin cu khoahc cng nh trong kim tra cng nghip,phng php ny cng c nhnghnchnhtnh:

Bngphng php phhngngoi khng chobit phn tlng(trtrnghpcbit). Ni chung ph hng ngoi khng cung cp

thng tin v cc v tr tngica cc nhmchc khc nhau trn mt phn t.

- Chring phhngngoi th i khi cha thbit l cht nguyn cht hay chthnhp vc trnghp 2 cht c phhngngoigingnhau.


17/88

17

ng dng :1.Nhnbit cc cht - Trc khi ghi phhngngoi, ni

chung ta c th c nhiu thng tin vhpchthoc

hn hp cn nghin cu, nh: trng thi vt l, dng

bn ngoi, tan, im nng chy,im chy.

Nu c th th cnbitchcmu l cht nguyn cht

hay hn hp. Sau khi ghi ph hng ngi, nu cht

nghin cu l hp cht hu c th trc tin nghin

cu vng dao ng co gin ca H xc nh xem

mu thuc loi hp cht vng thm hay mch thng

hocc hai.


18/88

18

Sau nghin cu cc vng tns nhm xc

nh c hay khng c cc nhm chc.Trong nhiu trng hp vic c ph (gii ph)

v tm cc tnsc trng khng nhn

bit mt cch ton din v cht nghin cu,nhng c l l c th suy onckiuhocloihpcht.

2. Xc nh tinh khit.

3. Phn tch nhlng.


19/88

19


20/88

20


21/88

21


22/88

22


23/88

23


24/88

24


25/88

25


26/88

26


27/88

27


28/88

28


29/88

29


30/88

30


31/88

31


32/88

32


33/88

33


34/88

34


35/88

35


36/88

36


37/88

37


38/88

38


39/88

39


40/88

40


41/88

41


42/88

42


43/88

43


44/88

44


45/88

45


46/88

46


47/88

47


48/88

48


49/88

49


50/88

50


51/88

51


52/88

52


53/88

53


54/88

54


55/88

55


56/88

56


57/88

57


58/88

58


59/88

59


60/88

60


61/88

61


62/88

62


63/88

63


64/88

64


65/88

65


66/88

66

Hng dn Gii Ph IR - NMR

Ph hng ngoi (FT-IR) v ph cnghng t ht nhn (1H-NMR, 13C-NMR)c coi l 2 cng ccbnnhtthc

hin php xc nhcu trc cc hpchthuc.

Cc bcthchinvicgii 1 bi tpv

phvi cng thctng qut cho trc:

BC 1. Tnh KHNG BO HA (degree of


67/88

67

BC 1. Tnh KHNG BO HA (degree ofunsaturation - DU) t trong cng thc tng qut xem trongphn t c bao nhiu vng, bao nhiu lin kt i.

Gi s ta c 1 cng thc l CnHmXi- Nu X l Halogens th coi n l H => CnHm+i- Nu X l O, S th b => CnHm- Nu X l N th tr i H tng ng => CnHm-i

DU= n - m/2 + 1

VD: C5H10O => DU = 5-10/2+1=1C8H11N => DU =8-10/2+1 = 4

NU:DU = 1c th c 1 LK i hoc vngDU = 2c th c 2 LK i, 2 vng, 1 LK ba hoc 1 LK i + 1 vngDU = 3c th c 3 LK i, 3 vng, 1 LK i + 2 vng, 2 LK i +

1vng, 1 LK ba + 1 LK i hoc 1 LK ba + 1 vngDU = 4ngh ngay ti vng benzenDU = 5c th l vng benzen + 1 LK i hoc vng benzen + 1 vngDU = 6c th l vng benzen + 2 LK i hoc 2 vng hoc 1 LK ba

hoc 1 LK i + 1 vng.

BC 2 Nhn vo ph IR ti vng s sng


68/88

68

BC 2.Nhn vo ph IR ti vng s sngln hn 1500cm-1

Kt hp cc d kin c t cng thc tng qut, DU v phIR: nu

Nu c 1 lin kt i v nguyn t O c th ngh ti nhmcarbonyl

Nu khng c lin kt i m li c O th c th ngh tiether hoc ru

BC 3.S dng ph NMR xc nh cc

lin kt trong phn tT cc nhm chc xc nht B2, vitcu trc phn t vda vo ph NMR nh gi xem cng thchp l cha.

BC 4 Kim tra s O C H Hal xem


69/88

69

BC 4.Kim tra s O, C, H, Hal, ... xem ph hp vi cng thc tng qut cha.

Kim tra ha tr cc nguyn t xem ph hpcha

Nu cha ng, vit cu trc phn t khc v

kim tra li

Tn s dao ng c trng ca


70/88

70

Tn s dao ng c trng caph IR


71/88

71

Chng 2: Ph NMR

Ph 1H-NMR l mtk thutsdngxc nh cu trc ha hc ca hp chthu c. Ph proton cho ta bit c s

loi proton c trong phn t . Mi loiproton s c tnh cht khc nhau v ths c dchchuyn khc nhau trn phproton. Ngi ta s dng TMS ( tetra

methyl silan ) lm cht chun trong phproton v dch chuyn ha hc caproton trong TMS cchn l 0 pmm


72/88

72

S tng tc ca cc proton (H) xung quanh s gy ra stch vch theo quy tc (n+1):1.singlet

2.doublet3.triplet

4.quartet

5.pentet6.sextet

7.septet

8.octet...


73/88

73

dch chuyn ha hc (chemical shift) ca

Hydrogen ph NMR0,9ppm: RCH3 1 aliphatic1,3ppm: R2CH2 2 aliphatic1,5ppm: R3CH 3 aliphatic

2 - 2 7 ppm: nhm ti v tr ny lin
http://i262.photobucket.com/albums/ii94/nguyenlebk/2-11-20108-13-05AM.jpg


74/88

74

2 - 2,7 ppm: nhm ti v tr ny linkt vi nhm carbonyl

3 7 - 4 1 ppm: nhm ti v tr ny


75/88

75

3,7 - 4,1 ppm: nhm ti v tr nylin kt vi nhm oxygen


76/88

76

9 - 10 ppm: nhm aldehyde

6 5 - 8 5 ppm: Aromatic


77/88

77

6,5 - 8,5 ppm: Aromatic

2,2 - 3 ppm: H ca nhm gn vo Aromatic


78/88

78

10 - 13,2 ppm: acid

0 5 - 3 ppm: amin aliphatic


79/88

79

0,5 3 ppm: amin aliphatic

3 - 5 ppm: amin Aromatic

4 - 4 4ppm: H ca nhn gn vi


80/88

80

4 4,4ppm: H ca nhn gn viNO2

4 12 H


81/88

81

4 - 12ppm: H ca ru

Alk l H lid


82/88

82

Alkyl Halides

Ph 13C NMR


83/88

83

Ph 13C - NMR

Nu nh ph 1H-NMR cho cc tn hiuca cc loi H th 13C-NMR cho cc tnhiuca cc loi C v thvi cc chthu

ckthp 2 ph ny c th xc nhccu trc ca hu ht cc cht.

Bng tm tt dch chuyn ha


84/88

84

Bng tm tt dch chuyn hahc trong ph 13C-NMR

Tng quan so snh gia 1H-NMR


85/88

85

Tng quan so snh gia 1H NMRvi 13C-NMR


86/88

86


87/88

87


88/88

Documents

Pho Hong Ngoai Ir7