tures containing these classes of compounds as well as in the analysis of alcohols. ACKNOWLEDGMENT
The authors wish to express appreciation to Janet L. Shultz for the tabulation of the mass spectra. LITERATURE CITED
Brown, R. A., Young, W.S., Nicholaides, Nicholas, AXAL.CHEM.26, 1653 (1954). Charlet, E. M., “Mercury-OrificeType-Inlet-System,” Consolidated Engineering Carp. Mass Spectrometer Group meeting, Kew Orleans, La., 1950. Dibeler, 1’. H., Mohler, F. L.,
Reese, R. M., J . C h e w Phys. 21, 180 (1953). (4) Eden, Murray, Burr, B. E., Pratt, A. AXAL. CHEM. 23, 1735 (1951). (5) Friede1,’R. A , , Sharkey, A. G., Jr., J . Chem. Phys. 17,584 (1949). (6) Friedel, R. A., Shultz, J. L.. Sharkev. A . G,, Jr.. ~ A L .CLEM. 281 926 (1956). ( i )Gifford, A . P., Rock, S. AI., Comaford, I). J., Ibid , 21, 9 (1949). (8) Happ, G. P., Sten-ard, D. W., J . Am. Chem. SOC.74, 4402 (1952). (9) Kellev, H. lI., A k s A L . CHElf. 23, lo81 (1951). ‘ (10) Langer, A., J . Phys. R. Colloid Chem. 54. 618 (19.50’1. (11) Lanier,-S.‘ H.: konnell, S., Wendw, I., J. Org. Chem., to be published. (12) Langer, S. H., Friedel, R. A . , Render, I., Sharkey, 9.G., “Use of Trimethvlsilyl Derivatives in the
w.,
M a s s S ectrometric Ana!?&. of Fischer-Gopsch Alcohols, Division of Petroleum Chemistry, 128th Meeting, ACS, Minneapolis, Ifinn., September 1955. (13) Sauer, R. O., J . Am. Chem. SOC.66, 1707 (1944). (14) Sharkey, A . G., Jr., Shultz, J. L., Friedel, R. A., ANAL.CHEM.2 8 , 934 (1956). (15) Stevenson, D. P., Hipple, J. A . , J . A m . Chem. SOC.64, 1588 (1942). (16) Thomas, B. W.,Segfried, IT. D., ANAL.CHEAf. 21, 1022 (1949). (17) Yarborough, V. A , : Ibid., 2 5 , 1914 (1953).
(18) Zemany, P. D., Price, F. P., J . Ana. Chem. SOC.70,4222 (1948). RECEIVED for review September 26, 1956. Accepted December 26, 1956. ASTM E-14 Cornmittfee Meeting on hIass Spectrometry, San Francisco, Calif., June 1955.
Infrared Spectra of Aliphatic Peroxya c id s ‘EDGAR R. STEPHENS, PHILIP L. HANST, and ROBERT C. DOERR The Franklin lnstifufe, Laborafories for Research and Development,
,The infrared spectra of peroxypropionic acid and peroxybutyric acid were recorded in the vapor phase from 2 to 15 microns. In addition to the C-H and carbonyl bands, the most prominent absorptions were found at 3.05 microns, 6.9 microns, and 8.5 microns.
I
x THE COURSE of an investigation of the photo-oxidation of hydrocarbons a t low concentration in air, samples of peroxypropionic and peroxybutyric acids nere prepared and their infrared spectra recorded in the vapor phase. GiguPre and Olmos have published the spectra of peroxyformic and peroxyacetic acids ( 2 ) . Their qpectrum of peroxyacetic acid vapor is similar to the spectra reported here. Minkoff has published spectra which he attributes to peroxyacetic, peroxypropionic, and peroxybutyric acids (3). However, as he himself indicates, his samples were impure. His spectrum of peroxyacetic acid is fimilar to the spectrum obtained b y GiguBre and Olmos, but his spectra of peroxypropionic and peroxybutyric acids are not similar either to the peroxyacetic acid spectrum or to the spectra reported in this work. The chief impurity in Minkoff’s samples appears to have been the ordinary aliphatic acids. These have been found to be persistent contaminents of the peroxyacids. THE SPECTRA
The spectra of perosypropionic and
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ANALYTICAL CHEMISTRY
0th and Parkway, Philadelphia
peroxybutyric acid are sho1vn in the upper portion of Figures 1 and 2. These acids are unstable; for that reason the spectrum of a fresh sample shon-s bands of decomposition products. After the spectra had been run, the samples were allowed to decompose in the cell and the spectra were rerun. Bands of the unstable peroxyacids can be identified if a comparison is made of the spectra obtained before and after decomposition. For comparison the spectra of pure propionic and butyric acid vapors were also recorded and are shown in the lower portion of Figures 1 and 2 . The spcctra w r e recorded on a Perkin-Elmer singlp-ham, single-pass spectrometer with the use of a PerkinElmer I-meter gas absorption cell. For each of the perovyacids the vapor pressure of the absorbing gas was about 3 or 4 mm. of mercury. The acid vapors were mived in the ahsorption cell with 1 atmosphere of dry, carbon diouide-free air which served to retard the decomposition of the pcrovT-acids. The peroxyacids shorn absorption bands usually ascribed to the stretching vibrations of C = 0 (5.7 microns), 0-0 (11.5 microns), and 02-H (3.05 microns), as well as other frequencies which apparently originate in the oxygenated part of the molecule. These are given in Table I. The chief distinguishing bands of peroxyacids appear, from these spectra, to be a t wave lengths of 3.05, 6.9, and 8.5 microns. The 3.05-band in particular is a useful indication of the presence of per-
Pa.
oxyacid in complex reaction mixtures. It is probably due t o the OH vibration and may, therefore, indicate that these spectra are those of the monomer and not the dimer. Giguere and Olmos ( 2 ) discuss in some detail the assignment of bands in the spectra of peroxyformic and peroxyacetic acids. PREPARATION A N D CHEMICAL PROPERTIES
The perosyacids were prepared by the method of Fischer, Dull, and Volz (1) which is essentially as fol1on.s. Aldehyde, in ice-cold carbon tetra-
Table I.
Infrared Absorption Bands of Peroxyacids
Frequency, Kave Length, Cm.-1 Microns 1ntensit.v” 3280 2940 1760 1450 1180 1000 875 805
Pcrosypropionic .kid 3.05 3.40 5.68 6.90 8.48 10.00 11.43 12.42
hf
S S s S
IT 11 11-
Perosybutyric Acid ?\I 3280 3.05 S 2940 3.40 s 1760 5.68 S 1450 6.90 S 1175 8.52 862 11.6 IV a S = strong; l f = medium; W = weak.
WAVE
I
2
3
4
5
(microns)
LENGTH
7
6
8
9
1
1 0 1 1
2
1
3
1
4
1
5
100
80
KO
4
Y
z
0
Figure 1. Peroxypropionic acid and decomposition products
40 c -
z
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