Dec., 1942
THEDIPOLE MOMENT OF VZS-TETRAPHRNYLPORPHINP
2993
[CONTRIBUTION FROM THE COLLEGE OF PHARMACY OF THE UNIVERSITY OF CALIFORNIA]
The Dipole Moment of ms-Tetraphenylporphie BY W. D. KUMLER The configuration of the porphine ring system zero, result in a very small difference in the dielecis of much interest because of its presence in chlo- tric constant of the various solutions. As a rerophyll and hemoglobin. A dipole moment study sult the experimental error in both Pz,and PE,,is of a compound such as ms-tetraphenylporphine probably about 7 cc. The value of 310 for P2, and 293 for PE,, indiappeared to offer a way to tell whether the compound and, hence, the ring system was symmetri- cates that the compound has a small or zero moment. The experimental error is of such magnical or unsymmetrical. The ms-tetraphenylporphine used in these tude that a moment of a few tenths cannot be disstudies was the more abundant isomer with a hy- tinguished from a moment of zero. It is probable drochloric acid number of 13.5.' The compound that this large highly resonating molecule has a is highly colored and absorbs appreciably in the comparatively large atomic polarization of the yellow, hence, the usual method of determining order of the difference between P2, and PEro. the electronic polarization by measuring the reThe polarization of the compound was also defractive index with the D sodium line could not be termined at 5' intervals between 25' and 45" but used. However, it appeared if light were used of no decrease in polarization with increasing tema wave length that was not absorbed by the com- perature was observed which likewise indicates pound the refractive index might be measured de- the compound has zero moment. spite the fact that the compound is highly colored. With zero moment the molecule must be arThe orange 6143 line in a neon tube was found to ranged in some symmetrical fashion. A symbe a suitable source. Abnormalities in the re- metrical structure might exist with the giant ring fractive index, which might have been expected either puckered or flat. The giant ring is, howhad the wave length of light used been too near an ever, a highly resonating system and the atoms absorption band, were not observed. must get into such a position that the alternate single and double bonds can shift their position Results without involving an appreciable movement of the The results are given in Table I. atoms. This demands a flat structure with the TABLE I giant ring, the pyrrole rings and the 1 and 4 carMEASUREMENTS IN BENZENE AT 25' bon atoms of each benzene ring all in one plane. 0 2 €12 u12 The two hydrogen atoms in the center can con2.2777 1.1454 0.002010 ceivably be arranged symmetrically in a number of 2.2807 1.1447 .004458 ways. First, on opposite nitrogen atoms with 2.2816 1.1442 .005595 2.2834 1.1436 .006762 one hydrogen above and one below the plane of the 2.2851 1,1435 .007916 main ring. Second, as above but forming hydro€1 u1 a -6 PZ, p% gen bonds to one of the adjacent nitrogen atoms. 2.2742 1.1460 1.355 0.311 310 293 Third, in the plane of the main ring and forming The P2, value was calculated by using the equa- a bifurcated hydrogen bond with both adjacent tions nitrogen atoms (as in the figure). Fourth, the same as in the second case except the covawhere the symbols have the same significance as lence to each hydrogen in the previous paper.2 shifts (resonates), being The values of a, p, vl, and €1 were determined attached first to one and graphically. A combination of three factors, then to the other nitronamely, the large size of the molecule, its low solugen atom. Fifth, the bility, and the fact that its moment is small or same as in the third case (1) Rothemund and Menotti, THISJOUBNAL, 68, 267 (1941) except the covalence to ms-Tetraphenylporphine. (2) Halverstadt and Kumler, ibld., 64, 2988 (1942).
2994
L.
PAULING,
D. PRESSMAN, D. H. CAMPBELL, c.IKEDA AND M. IKAWA
Vol. 64
each hydrogen shifts among three nitrogen atoms. refractometer using a neon Geissler tube as a light Case one is unlikely because it appears highly prob- source. able that hydrogen bonds are p r e ~ e n t . If~ ~the ~ ~ ~ The ms-tetraphenylporphine was recrystallized actual situation is that of case four or five, which twice from benzene. does not appear at all unlikely, there would be no Acknowledgment.-We are indebted to Dr. isomerism due to the position of the hydrogen 0. L. Inman and Dr. Paul Rothemund of the atoms. C. F. Kettering Foundation a t Antioch College It appears from a study of the Fisher models for the sample of ms-tetraphenylporphine. that a flat giant ring of this type can be consummary structed without undue strain. However, there The more abundant isomer of ms-tetraphenylis much interference between the pyrrole rings porphine was found to have a polarization of 310 and the benzene rings if an attempt is made to place the latter in the same plane as the rest of the and an electronic polarization of 297. Measurement of polarizations a t different temperatures molecule. This suggests that the benzene rings gave no evidence of a decrease of polarizations do not have free rotation and are probably oscillating about a position perpendicular to the plane with increasing temperatures. Both methods of the main ring. The general shape of the mole- indicate the compound has zero moment although cule would then be that of a flat disc with the four the data do not enable one to distinguish between benzene rings cutting it at about right angles. a moment of a few tenths and a zero moment. The electronic polarization of the compound If the benzene rings do not have free rotation was obtained by measuring the refractive index of then derivatives of ms-tetraphenylporphine havthe solutions although they were highly colored. ing ortho or meta substituents should exist in a This was accomplished by using the orange line number of stereoisometric forms depending on of a neon tube. This light had a wave length whether the substituents are above or below the that was not absorbed by the solution. plane of the giant ring. The zero moment indicates the compound is Experimental symmetrical. The resonance demands that the The dielectric constant measurements were giant ring and the pyrrole rings be in one plane. carried out with the same apparatus and in the A study of the Fisher models suggests the benzene same manner as described previously.6 The re- rings do not have free rotation and are perpenfractive indices were measured with a Pulfrich dicular to this plane. With ortho or meta substituents on the benzene rings this hindered rota(3) Corwin and Quattlebaum, THIS JOURNAL, 68, 1081 (1936). (4) Vestling and Downing,&id., 61, 3511 (1939). tion will give rise to a number of stereoisomers. ( 5 ) Aronoff and Weast, J . Org. Ckcm., 6, 550 (1941). Sm FRANCISCO, CALIF. RECEIVED SEPTEMBER 24, 1942 ( 6 ) Kumler, T m s JOURNAL, 62, 3292 (1940).
______~ [CONTRIsUTION FROM THE GATES AND CRELLIN LABORATORIES OF CHEMISTRY, CALIFORNIA INSTITUTE OF
No. 8851
TECHNOLOGY,
The Serological Properties of Simple Substances. I. Precipitation Reactions between Antibodies and Substances Containing Two or More Haptenic Groups BY LINUSPAULIKG, DAVIDPRESSMAN, DANH. CAMPBELL, CAROLIIZEDA, AND MIYOSHIIKAWA ’The study of serological precipitation reactions is complicated by the fact that ordinarily these reactions involve two proteins, the antigen and the antibody. The understanding of these reactions was greatly advanced by the introduction into their study of precise microanalytical methods and a further simplification involving the use of a nitrogen-free multivalent hapten of pneumococcus polysaccharide.‘ A few years ago i t was reported (1) M. Heidelberg-
and F. E. Kendall, 1. BxPfI. Mcd., SO, 809
(1929): 81, X 4 , 563 (IB35).
by Landsteiner and van der Scheer2=that the
precipitin reaction and anaphylaxis could be produced by simple substances formed by coupling two haptenic groups with resorcinol or tyrosine, in place of the azoprotein (containing the same haptenic group) which has been used as the antibody-producing antigen. LandsteinerZbsuggested that “the ready precipitability of these (2) (a) K. Landsteiner and X, van der Scheer, P ~ o GSOC. . Exfill. B i d M t d . , %S, 747 (1982); J . Ezfill. Mcd., 56, 399 (1632);61.633 (1933), 87, 79 (1938). (b) K . Landsteinar, “The Specifioity of Serological Reactions,” Charles C Thomas, Baltimore, Md., 1936,p. 120.
