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Vol. 73
and Cu++, -26.5 e.w2 the value S$+ =, +X.3 rt 2.0 e.u. is found. In view of the relation of Powell and Latimers connecting the ionic radii and the partial molal entropies of aqueous ions this value seems more reasonable than the Bureau of Standards value.
we have observed low “carbonyl” frequencies are 3J’- and 4,4’-dibenzanthronyl (1626 and 1630 em. -1, respectively). An insufficient number of
(I) M. L. Josien and N. Fuson, THIS JOURNAL, 7s, 478 (1951). (2) M. St. C. Flett, J. Chcm. SOC.,1441 (1948).
(1) Paper No. 26, Division of High Polymer Chemistry, American ChemicaI Society Meeting. September 6. 1960.
orthoquinones seem to have been studied spectroscopically to enable correlation rules to be drawn up at present. In picking out the “carbonyl” frequencies we ( 5 ) R. E. Powell and W. XI Latimer, J . Chcm. Phys., 19, 1139 have listed the strong absorption band for each (1951). coinpound which lies a t the highest frequency in DEPARTMENT OF CHEMISTRY the region 1550 to 1750 cm -I. I t is of interest UNIVERSITY OF CALIFORXIA RECEIVED JUSE 14, 1931 to note however that in some cases other equally BERKELEY, CALIFORXI.\ strong absorption bands occur in the infrared spectrn in the region 1570 to 1600 ~ m . - ~ As . ~the The “Carbonyl” Frequency in Polycyclic Quinones skeletal vibrations of polycyclic ring systems often occur i n this range4 it seems probable that, as BY I).HADZIAND N. SHEPPARD niight be expected, several of these modes of vibraIn a recent communication Josien and Fuson’ tion also involve considerable vibrational motion have pointed out that the “carbonyl” frequency in of the carbonyl linkages. This coupling with ring some polycyclic compounds, mainly quinones, has skeletal vibrations would explain a t the same time an abnormally low value in the infrared spectrum the high intensity of these lower frequency absorp(e.g., 6.1 p or approximately 1640 cm-l for 3,s- tion bands and the variable nature of the so-called and 3,lO-pyrenequinone). In connection with carbonyl frequency itself. In all cases that we some work on coking substances and c o d extracts, have so far investigated only very much weaker we have also studied the infrared spectra of a bands are found in the region 1550-1750 cm series of polynuclear quinones and some related for the corresponding hydrocarbons. hydrocarbons. h selection of the “carbonyl” On further comparison of the spectra of the frequencies that have been obtained in Nujol quinones and related hydrocarbons, differences mulls of the quinones are listed below and may be were also found in the regions of the spectra which compared with the values of 1660 c ~ i i . - (6.01 ~ p) are not close to the “carbonyl” frequency. Thus in for p-benzoquinone and 1676 cni --I (5.97 p ) for the spectra of the quinones strong absorption bands anthraquinone, obtained previously by Flett.? were found in region 1200-1350 cm.-’ which are not cm. - I 9 present in comparable strength in the hydrocarbon 6.01 spectra, and presumably also arise from the coupling p Saphthoquiuone 1664 6.04 Pyranthrone 16% of the C 4 vibration with those of the rest of the 6.06 molecule. In addition the features in the spectra of hIesonaphthadisnthrone 1649 6.08 the quinones and hydrocarbons between 900 and Helianthrone 1646 6.08 1,2;6,7-Dibenzpyrene-3 ,d-quinone 1645 700 cm.-1 which can usually be attributed to the 6.10 out-of-plane vibrations of the CH linkages attached Llibenzanthrone 1638 6.16 to the aromatic skeleton4 also showed considerable Diphenoquinone 1626 differences as would be expected from the changes in I t can be seen that the “carbonyl” frequencies substitution pattern. Further spectroscopic work of the polynuclear quinones listed above vary con- on these types of molecules is continuing. siderably in value. Taking into account these IVe are very grateful toProfessorA.R.Todd, F.R.S. results and those of the earlier workers1V2it appears and Dr. A. W. Johnson of the University Chemical that paraquinones in which the two quinone carbonyl groups occur in the same ring absorb in Laboratory, Cambridge, and to Imperial Chemical the range 1660 to 1680 cm.-l, and that extended Industries (Dyestuffs), Ltd., for samples of the quinones, in which the carbonyl groups are in substances studied. (3) A similar eBect has been noted previou4y as being caused by t h e different rings, usually absorb in the range 1635 conjugntion of a C-0 group to n phenyl ring (Randall. Fowler, F u w n to 1655 an.-’, In confirmation of this latter r n d Dnngl, “Infra-rrd Deicrmiination of Organic Structures,” D \‘an point we have found that benzanthrone has its Sostrand and C o , S e w York, N Y , 194q, p 10) (4) S F D. Orr and 13 \v Thompson, J Chem. Soc , 218 (1930) “carbonyl” band at 1644 rrn.-l, and anthrone has been shown previously to absorb a t 1654 an.-’2; K E M I ~ N INST. I SLOVENSKE AKADEMIJE both of these molecules have single carbonyl groups ZNANOSTI, LJUBLJANA, JUGOSLAVIA, AND DEPARTMENT OF COLLOID SCIEXCE coupled in a similar fashion to polycyclic ring FREE SCHOOL LANE systems. A single exception to the above rule CAMBRIDGE, EXGbAXD concerning the “carbonyl” frequencies of extended quinones is provided by diphenoquinone. Viscosity of Polytrifluorochloroethylene in However this result may be abnormal on account o-Chlorobenzotrifluoride of the unusual structure and chemical properties of this molecule. In any case the above correla- R Y H. TRACYTIALL. l?DWARD L. BRADYA V n r’AI‘1 1) ZEMANT tions must only be considered as provisional and as subject to refinement when the spectra of a more Viscosity data for polytrifluorochloroethylene in extensive series of molecules of this type become a chlorofluorobutane solvent have been presented available. Other quinone type molecules for which by H. S. Kaufman and hl. S. Muthana.‘ We
