C13 NUCLEAR MAGNETIC RESONANCE (NMR)

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Presentation transcript:

C13 NUCLEAR MAGNETIC RESONANCE (NMR)

13C NMR C13 resonances occur from 0 to 200 ppm (δ). These peaks are split by the attached hydrogens. However, proton decoupled (broadband) spectra are not split by H.

13C NMR Distortionless enhancement by polarization transfer (DEPT) spectra permit identification of CH3, CH2, and CH carbon atoms. DEPT 45 shows 1o, 2o,and 3o carbons. DEPT 90 shows only 3o carbons. DEPT 135 shows 1o and 3o carbons as positive peaks and 2o carbons as negative peaks.

13C NMR

13C Off-resonance decoupled spectrum

13C Off-resonance & Broadband decoupled spectra

13C Broadband decoupled spectrum

13C NMR – n-Hexane Broadband

13C NMR – Acetone Broadband

1H & 13C NMR: 1,1,2-trichloropropane Broadband

1H & 13C NMR: 2-methyl-2-butene Broadband

1H & 13C NMR: 2-methyl-1-butene Broadband

13C NMR – 6-methyl-5-hepten-2-ol Broadband All carbons as singlets

13C NMR – 6-methyl-5-hepten-2-ol DEPT 90 Only CH carbons

13C NMR – 6-methyl-5-hepten-2-ol DEPT 135 Methyl and CH positive Methylene negative

END C13 NMR