1 / 7

FTIR -- InfraRed

FTIR -- InfraRed. IR 1. Bet vis & microwave 2. Organic chemists use 4000 - 400 cm -1 3. cm -1  E of vibration. No 2 cmpds give exact sample IR (enantimoers) 2 types of molecular vibration stretching bending 3 vibrations

germane-meyer
Download Presentation

FTIR -- InfraRed

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. FTIR -- InfraRed IR 1. Bet vis & microwave 2. Organic chemists use 4000 - 400 cm-1 3. cm-1 E of vibration No 2 cmpds give exact sample IR (enantimoers) 2 types of molecular vibration stretching bending 3 vibrations symmetrical asymmetrical scissoring

  2. Stretching Frequencies () C-C C-O C-N 1300 - 1500 cm-1 C=C C=O C=N N=O 1900 - 1500 C C C N 2300 - 2000 C-H O-H N-H 3800 - 2700 2 imprt areas for prelim exam of spectra 4000 - 1300 900 - 650 1300 - 900 fct group region fingerprint complex Imprt for -OH NH C=O strong bands 1600 - 1310 aromatics (benzene ring) 900 - 650 strong out-of-plane bending & ring bending

  3. C - H Stretch Alkanes 3000 - 2840(s) other: near 1375 & 1450 Cycloalkanes 3100 - 2990(m) other: near 1450(m) Alkenes above 3000(s) other: near 1416(m); 1000-650(w); near 850(s) Alkynes 3333 - 3267(n,s) stronger-narrower than OH & NH other: 700-610(b,s); 1370-1220(w,o) Aromatics 3100 - 3000 & 2000 - 1650(w,o) other: 900-675(s); 1300-1000(m) Aldehydes 2830 - 2695(2:s) w/ near 1390 other: near 2720(m)

  4. C to C Alkanes below 500; 1200 - 800(w) are of little value best is C-H CH3 2962 & 2872 CH2 near 2926 & near 2853 (+/-10) CH near 1375 & near 1450 Alkenes 1667 - 1640(m) Alkynes 2260 - 2100(w)

  5. ALCOHOLS -- PHENOLS Alkenes - Phenols -OH & C-O OH 3650 - 3584(b,s); 1420 - 1330(m) CO 1260 - 1000(s) ETHERS Ethers C-O-C similar to C-C-C but more intense 1150 - 1085(s)

  6. CARBONYL C=O containing Carbonyls (ketones, aldehydes, carboxylic acids, esters, anhydrides, amides) C=O 1870 - 1540(s) Ketones 1300 - 1100(m) Aldehydes 1740 - 1720 C-H 2830-2695(2:m) & near 2720(m) Carboxylic Acids O-H 3300 - 2500(b,s) C=O near 1766(s) C-O & O-H near 1320-1210(m) & near 1440-1395(m) Esters C=O 1750 - 1715(s) higher freq than ketones C-O 1210- 1163(2:s)

  7. NITROGEN CONTAINING Amides NH2 or NH 1650 - 1515 other: near 3520(m) & near 3400(m) C=O 1694 & 1650(s) C-N near 1400(m) Amine N-H near 3500(w) & near 3400(w) other: NH 1650-1580(m) C-N 1250 - 1020(m) aromatic C-N 1342-1266(s) Nitriles C=N 2260 - 2222(m)

More Related