DEPT-NMR spectrum

Figure 13.10 DEPT-NMR spectra for 6-methyl-5-hepten-2-ol. Part fa) is an ordinary broadband-decoupled spectrum, which shows signals for all eight carbons. Part [b) is a DEPT-90 spectrum, which shows only signals for the two CH carbons. Part (c) is a DEPT-135 spectrum, which shows positive signals for the two CH and three CH3 carbons and negative signals for the two CH2 carbons.

The 13C NMR spectrum of valproic acid was obtained using a Bruker Avance Instrument operating at 75, 100, and 125 MHz. Standard Bruker Software was used to obtain DEPT spectra. The sample was dissolved in D20 and tetra-methylsilane (TMS) was used as the internal standard. The 13C NMR spectrum of valproic acid is shown in Fig. 10. The DEPT NMR spectra are shown in Figs. 11 and 12. The assignments for the various carbons of valproic acid are presented in Table 4. 

Figure 4. C 1FI [ DEPT NMR spectra for DVB and St monomers and 13C CP/MAS NMR spectra for DVB-St copolymers filled with methyl- (/) and methyl,hydride-containing silicas (2).

Dianchinenoside E was assigned a molecular formula of C57H92O26 from its positive ion FABMS ([M+Na]+ at m/z 1215) and 13C DEPT NMR spectra. Of the 57 carbons, 30 were assigned to the aglycone part, 24 to the oligosaccharide moiety, and 3 to a 1,2-propanediol group. The IR spectrum showed absorptions at 3405 cm 1 (-OH) and 1718 cm 1 (ester). Acid hydrolysis of the... 

FIGURE 9.30 (a) The broadband proton-decoupled NMR spectrum of 1-chloro-2-propanol. (b) These three spectra show the DEPT NMR data from 1 -chloro-2-propanol (see Section 9.11D). (This will be the only full display of a DEPT spectrum in the text. Other NMR figures will show the full broadband proton-decoupled spectrum but with information from the DEPT NMR spectra indicated near each peak as C, CH, CH2, or CH3.)... 

FIGURE 9.31 The broadband proton-decoupled NMR spectrum of methyl methacrylate. Information from the DEPT NMR spectra Is given above the peaks. 

F ure I. DEPT NMR spectra of l,3-bis(3-carboxypropyl)-tetramethyldisiloxane(top), a,p-ethylglucoside(middle), andl,3-bis(l -ethylglycosyl-6 -propionate) tetramethyldisiloxane (bottom). 

DEPT NMR spectra indicate how many hydrogen atoms are bonded to each carbon, while also providing the chemical shift information contained in a broadband proton-decoupled NMR spectrum. The carbon signals in a DEPT spectrum are classified as CH3, CH2, CH, or C accordingly. 

Compounds A, B, and C are isomers with the formula CsHiiBr. Their broadband proton-decoupled NMR spectra are given in Fig. 9.32. Information from the DEPT NMR spectra is given near each peak. Give structures for A, B, and C. 

Information from the DEPT NMR spectra is given above the peaks. 

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