Raman Spectrum of an Aqueous Solution of Potassium Cyanate

Raman Spectrum of an Aqueous Solution of Potassium Cyanate...
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Preparation of o-Nitrosophenols from Benzene or Other Aromatic Hydrocarbons at Room Temperature BY OSKARBAUDISCH

Vol. 63

lived nitrosyl radical NOH is captured and brought into chemical reaction with inserted ethylene groupings. (1) Science, vol. No. 2389, 336 (1940).

STATERESEARCH INSTITUTE OF THE SARATOCA SPA SARATOGA SPRINGS, N. Y. RECEIVED OCTOBER 28, 1940

Sodium pentacyano-ammine-ferroate (ammin salt) (2 g.) was dissolved in 100 cc. distilled water and 25 cc. of benzene as well as 50 cc. of ligroin added and the mixture cooled with ice water. Raman Spectrum of an Aqueous Solution of Now 2 g. of NHZOH-HCl is dissolved in the Potassium Cyanate‘ solution (color changes from brown to grass BY FORREST F. CLEVELAND green) and 4 cc. of Merck superoxol added. (Color In a recent investigation of the infrared abchanges from grass green to deep brownishsorption spectrum of a saturated aqueous soluviolet.) Already, a few minutes after adding the tion of potassium cyanate, Williams2 found inhydrogen peroxide o-nitrosophenol can be detense bands for the freshly prepared solution a t tected in the ligroin layer. After shaking violently 870 and 2170 ern.-' which were attributed to funfor one hour, the color of the benzene-ligroin layer damentals vl and vg, respectively, of the linear is deep green, due to the formation of larger group. After the solution had stood amounts of o-nitrosophenol. The green benzene- O-C=Nfor several days, additional absorption bands were ligroin part (aqueous part P) is now separated, observed a t 1350, 1690 and 2860 ern.-'. These washed with ice water and shaken with dilute bands were attributed to absorption by amcopper sulfate solution. A deep red water soluble monium and carbonate groups formed by hydrolyo-nitrosophenol copper salt (Sol. C) is formed sis. The present note is a report of a Raman while the benzene-ligroin becomes entirely colorspectra study undertaken to supplement the inless and is used for further extraction of the frared data. aqueous part P. After shaking for one or two Experimental hours the deep green benzene-ligroin is again separated and o-nitrosophenol converted into Ten cc. of an approximately saturated solution the red copper salt (Sol. C). The aqueous part of “c. P. Baker’s Analyzed” potassium cyanate is now diluted with 100 cc. of water and several was prepared and a one hour exposure made imtimes extracted with ligroin until the ligroin is mediately. Following this a polarization speconly pale green in color. The copper salt solu- trogram was made and the solution stored in a tions C, C1,etc., are united, and in presence of closed test-tube. One hour exposures were made petrol ether acidified with hydrochloric acid. The on successive days over a ten day period and deep green petrol ether is washed with ice water finally a polarization spectrogram of the aged free from excess acid. It keeps protected from solution was made. light in the cold for weeks unchanged. Details regarding the experimental technique If benzene is replaced by toluene, ethylben- have been given in previous papers3 The zene, xylene, phenylacetylene, chloro- or bromo- 4358 8.mercury line was used for excitation of the benzene, similar results are obtained but with spectra. varying yields. Results Sodium pentacyano-ammine ferroate can, howThe results are summarized in Table I. Colever, not be replaced by ordinary ionized iron umns one, two and three give the Raman dissalts. In repeating the described experiment placements in cm.-’, estimated intensities and dewith ferrous sulfate (2 g.) only traces of o-nitropolarization factors for lines in the spectrum of the sophenol are formed. fresh solution, while columns four, five and six In the complex sodium pentacyano-aquogive the corresponding data for the aged solution. ferroate, which is formed from the ammin salt in (1) Presented at the Seattle, Washington meeting of the American the acid medium, the sixth free valence of the Physical Society, June 21, 1940. ferrous central atom shows an exceptionally (2) Dudley Williams, THIS JOURNAL, 62, 2442 (1940). Forrest F. Cleveland and M. J. Murray, J . Chcm. Phys., 7, great chemical affinity to NO compounds. This 396(3)(1939); M.J. Murray and Forrest F. Cleveland, THIS JOURNAL, fact seems to be the main reason that the short- 61, 3546 (1939).

Feb., 1941

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TABLE I bonate, for which no data were found in the literaRAMAN SPECTRA OF FRESH AND AGED POTASSIUM CYANATE ture, gave lOSO(6)O.l and 1007(4)0.3, respectively. SOLUTION These data suggest the origins of the lines observed Fresh Solution

Au

I

P

.. ..

..

.. .. ..

... ...

1225 1315 2171

4 6 10

0.6 .6 .3

.*.

Av

Aged Solution I

1003 1033 1064

.. ..

..

8 8 10

.. .. ..

P

0.4 .3 .3

...

... ...

a t 1003, 1033 and 1064 in the spectrum of the aged potassium cyanate solution. DEPARTMENT OF PHYSICS RECEIVED AUGUST27, 1940 ILLINOIS INSTITUTE OF

CHICAGO, ILLINOIS

TECHNOLOGY

Some Tertiary Amides of Adipic, Azelaic and

In the spectrogram made on the third day, the Sebacic Acids lines observed for the fresh solution had disap- BY REYNOLD C. FUSON,JOHN W. ROBINSON, JR., AND peared and three new lines slightly above 1000 LYELLC. BEHR cm.-l had appeared. In addition, the solution Tertiary amides have been studied but little which originally had been odorless had acquired and those of the higher acids scarcely a t all. the odor of ammonia. Observance of NH4+ From the standpoint of solubility and basicity, lines was impossible because of the strong conthis type of amide is of especial interest in connectinuous background in that region. tion with the theory of hydrogen bonding. Primary and secondary amides, being able to serve a t Discussion Goubeau4found a weak line a t 857, a very weak, once as donors and as acceptors, are associated in questionable line a t 970 and a line of medium in- solution.’ They have, accordingly, lower solutensity at 2192 cm.-’ in the Raman spectrum of bility in water than that to be expected for the solid potassium cyanate. In aqueous solution, monomeric form. Tertiary amides cannot assohe found 852, very weak, and 2185, weak. Pal ciate through hydrogen bonding and hence do not and Sen Gupta6 also reported frequencies a t share this abnormality.2 Striking examples of 838 and 2183, and in addition listed frequencies these differences have been encountered with cera t 1229 and 1314, not found by Goubeau. These tain tertiary amides of adipic, azelaic and sebacic two frequencies were found also in the present acids, prepared in connection with the synthesis of diketones by the Beis3 method. The amides investigation. of this group are particularly interesting because As Williams points out, these lines cannot be solubility predictions based on structure place attributed to vibrations of the linear 0-CENthem near the borderline between so-called watergroup. The fact that Goubeau found lines a t soluble and water-insoluble compound^.^ That 1204 (weak) and 1307 (strong) for cyanic acid the primary and secondary amides fall in the suggests the possibility that there may be some latter group is evidence that they are associated. of this acid in the potassium cyanate solution. The new amides were made by the interaction of Another possibility is that mercury cyanate or acid chlorides with suitable secondary amines silver cyanate may have been present as an imaccording to the general procedure of Maxim6 purity. Goubeau found lines a t 1232 (weak) and and Montagne.6 They proved to be water1302 (medium) for the former and at 1233 (weak) soluble and were sufficiently basic to form hydroand 1297 (medium) for the latter. He attributed chlorides, chloroplatinates and chloroaurates. these frequencies to the doublet V I , 2 VI (analogous to the resonance doublet in carbon dioxide) of the Experimental linear O=C=N- group. N,N,N’,N‘-Tetraethyladipamide was made from diethylAqueous solutions of potassium carbonate and amine and adipyl chloride. After three recrystallizations potassium bicarbonate have Raman frequencies from low-boiling petroleum ether, it melted at 52.5-53.5’. a t 1069 and 1035 cm.-’, respectively.e Measure(1) Meldrum and Turner, J . Chem. Soc., 98, 876 (1908); 97, 1605, ments of the Raman spectra of aqueous solutions 1805 (1910); von Auwers, Bcr., 70, 964 (1937). (2) Chaplin and Hunter, J. Ckcm. Soc., 1114 (1937); 1034 (1938). of ammonium carbonate and ammonium bicar(4) J. Goubeau. Ber., 68, 912 (1935).

(5) N.N. Pal and P. N. Sen Cupta, Ind. J . Phys., I,11 (1930). (6) M. Magat, “Tables Annuelles d e Conrtantes et DonnCeo Numiriques, EEet Raman,” Volume XII, Hermann & Cie., Paris, 1837.

(3) Beis, Compf.rend., 187, 575 (1903). (4) Shriner and Fuson, “Systematic Identification of Organic Compounds,” 2nd ed., John Wiley and Sons, Inc., New York, N. Y., (1940,p. 10. (5) Maxim, Ann. chim., [lo]9, 58 (1928). (6) Montagne, i b i d . , [lo] 1%, 40 (1930).