2-Butanone infrared spectrum

In the infrared, 2-hydroxycyclobutanone has a carbonyl band at 1780 cm in chloroform solution. Kept in nitrogen-filled screw-capped vials in the freezing compartment of a refrigerator, 2-hydroxyoyolo-butanone slowly but completely solidifies as its dimer. The infrared spectrum of the solid in a KBr disk shows no carbonyl. However, a chloroform solution of the solid does show the characteristic 1780 em band, indicating rapid equilibration with the monomer. 

The remainder of this paper will describe specific applications of FTIR in support of one of Diamond Shamrock s pesticide programs. All the results described here were obtained from studies of a single compound, thiofanox (P), 3,3-dimethy1-1-methylthio-2-butanone 0-[(methylamino)carbonyl]oxime. Thiofanox is a potent systemic and contact carbamate insecticide. The infrared spectrum of thiofanox is shown in Figure 4. The major peaks in the spectrum are the N-H stretch at 3380 cm-1,... 

The conformational profile for 2-butanone has been developed from analysis of its infrared spectrum. The dominant conformation is anti with a C(1)H and the C(4) methyl group eclipsed with the carbonyl. 

An infrared spectrometer determines the positions and relative sizes of all the absorptions, or peaks, in the infrared region and plots them on a piece of paper. This plot of absorption intensity versus wavenumber (or sometimes wavelength) is referred to as the infrared spectrum of the compound. Figure 2.4 shows a typical infrared spectrum, that of 3-methyl-2-butanone. The spectrum exhibits at least two strongly absorbing peaks at about 3000 and 1715 cm for the C—H and C=0 stretching frequencies, respectively. 

FIGURE 2.4 The infrared spectrum of 3-methyl-2-butanone (neat liquid, KBr plates). 

Figure 12.2 is an infrared spectrum of 3-methyl-2-butanone. The horizontal axis at the bottom of the chart paper is calibrated in frequency (wavenumbers, cm ) that at the top is calibrated in wavelength (micrometers, ju,m). The frequency scale is often... 

The H NMR spectrum of a compound with formula C6H12O2 is shown. The DEPT experimental results are tabulated. The infrared spectrum is rather uninteresting. There are four strong bands that appear in the range of 1200 to 1020 cm. The compound is prepared from the reaction of 1,2-ethanediol and 2-butanone. Draw the stmcture of this componnd. 

Figure 2.4 shows a typical infrared spectrum, that of 3-methyl-2-butanone. The spectrum exhibits at least two strongly absorbing peaks at about 3000 and 1715 cm for the C—H and C=0 stretching frequencies, respectively. 

A scientist working with a Fourier transform infrared spectrometer. Inset a modei of 3-methyi-2-butanone. For an IR spectrum of this compound, see Figure 12.2. 

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