columbia大学有机化学课件13_19 html

1、13.19Infrared SpectroscopyGives information about the functional groups in a moleculeregion of infrared that is most useful lies between 2.5-16 mm (4000-625 cm-1)depends on transitions between vibrational energy statesstretching bendingInfrared SpectroscopySymmetricAntisymmetricStretching Vibrations

2、 of a CH2 GroupIn planeIn planeBending Vibrations of a CH2 GroupOut of planeOut of planeBending Vibrations of a CH2 GroupFigure 13.26:Infrared Spectrum of Hexane350030002500200015001000500Wave number, cm-1Francis A. Carey, Organic Chemistry, Fourth Edition. Copyright 2000 The McGraw-Hill Companies,

3、Inc. All rights reserved.bendingCH stretchingbendingbendingCH3CH2CH2CH2CH2CH3Figure 13.27:Infrared Spectrum of 1-Hexene350030002500200015001000500Wave number, cm-1Francis A. Carey, Organic Chemistry, Fourth Edition. Copyright 2000 The McGraw-Hill Companies, Inc. All rights reserved.C=CC=CHHCH2C=CHCH

4、2CH2CH2CH3H2C=CStructural unitFrequency, cm-1Stretching vibrations (single bonds)sp CH3310-33203000-31002850-295012001025-1200sp2 sp3 sp2sp3CHCHCOCOTable 13.4 (p 519) Infrared Absorption FrequenciesStructural unitFrequency, cm-1Stretching vibrations (multiple bonds)1620-1680CC2100-2200CC2240-2280CNT

5、able 13.4 (p 519) Infrared Absorption FrequenciesStructural unitFrequency, cm-1COStretching vibrations (carbonyl groups)Aldehydes and ketones Carboxylic acidsAcid anhydrides EstersAmides1710-17501700-17251800-1850 and 1740-17901730-17501680-1700Table 13.4 (p 519) Infrared Absorption FrequenciesStruc

6、tural unitFrequency, cm-1Bending vibrations of alkenesRCHCH2910-990890R2CCH2cis-RCHCHR665-730trans-RCHCHR960-980790-840R2CCHRTable 13.4 (p 519) Infrared Absorption FrequenciesStructural unitFrequency, cm-1Bending vibrations of derivatives of benzeneMonosubstituted Ortho-disubstituted Meta-disubstitu

7、tedPara-disubstituted730-770 and 690-710735-770750-810 and 680-730790-840Table 13.4 (p 519) Infrared Absorption FrequenciesFigure 13.28:Infrared Spectrum of tert-butylbenzene350030002500200015001000500Wave number, cm-1Francis A. Carey, Organic Chemistry, Fourth Edition. Copyright 2000 The McGraw-Hil

8、l Companies, Inc. All rights reserved.ArHC6H5C(CH3)3HCMonsubstituted benzeneStructural unitFrequency, cm-1Stretching vibrations (single bonds)OH (alcohols)OH (carboxylic acids) NH3200-36003000-31003350-3500Table 13.4 (p 519) Infrared Absorption FrequenciesFigure 13.29:Infrared Spectrum of 2-Hexanol350030002500200015001000500Wave number, cm-1Francis A. Carey, Organic Chemistry, Fourth Edition. Copyright 2000 The McGraw-Hill Companies, Inc. All rights reserved.HCOHCH3CH2CH2CH2CHCH3OHFigure 13.29:Infrared Spectrum of 2-Hexanone350030002500200015001000500Wave number, cm-1Fr