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C 13 NUCLEAR MAGNETIC RESONANCE (NMR). 13 C NMR . C 13 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. 13 C NMR .
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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 Off-resonance & Broadband decoupled spectra Off-resonance Broadband
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