COMMUNICATIONS TO THE EDITOR
2714
by using the experimental value of n and letting l/3. In changing to this form the expressions for A , D,T , and 0.5 Cy Dz = 0 do not change but the other relations become w =
K -a
+
C
+
+ 3 - n - 0.30103q
[(’)‘Icr
n + a x - d2
= 1
- K + (w +
- !If
Vol. 39
The constants, as determined for nitrogen, are n = 3.427, C = 1.007, D = 0.24956, A = 6.78549, q = 0.72330, K = 0.38022, a = 0.01796, x = 0.16798, y = 0.3796.5, z = -3.53641, w = l / 3 , T~ = 2-48. By converting values found by this equation to n = 3.424, the value for argon, by means of the stretch formula the changes in volume correspond closely with the experimentally determined volume changes for argon‘ from 2000-15,000 kg./ sq. cm. a t 55’ and the volume a t 3000 kg./sq. cm. and 55’ is found to be 0.765 cc./g. (4) P. W. Bridgman, “The Physics of High Pressure,” The Macmillan, Co., New York, N. Y . , 1931.
VALENCIAHIGHSCHOOL PLACRNTIA, CALIF. RECEIVED SEPTEMBER 20, 1937
COMMUNICATIONS T O T H E EDITOR THE EFFECT OF HYDROXYL GROUPS ON THE APPARENT DIENE VALUES OF VEGETABLE OILS AND FATS
oil under various conditions of heat bodying. As in the case of Bruce and Denley, it was noted that the presence of hydroxyl groups led to anomalous Sir : diene values. Consequently, the M. A. V. and In a letter to the editor of Chemistry and In- diene value of a number of purified hydroxylated dustry, 56, 937 (1937), entitled, “Maleic Anhy- compounds were determined before and after dride Value or Diene Value,” R. J. Bruce and P. blocking the hydroxyl group by acetylation. The G. Denley called attention to certain anomalous compounds examined included methyl 12-hyresults which they obtained on determining the droxystearate, glyceryl monoricinoleate, methyl M. A. V. of oxidized linseed, perilla, and soybean ricinoleate, a-monopalmitin, a,a’-distearin, ethyloils. They state “It occurred to us that the ene glycol, acetone-glycerol, and glycerol. It was M. A. V. might not be solely indicative of conju- observed that in all but one case (ala’-distearin) gated double bonds, but that it might include any significant M. A. V. and diene values were observed maleic anhydride that entered into combination with the hydroxylated compounds; whereas, with hydroxyl groups already in the oil or formed following acetylation, the magnitude of these during oxidation.” values dropped in all cases to practically zero. In a similar manner were examined a variety of I n order to test the validity of this assumption they determined the M. A. V. of dihydroxystearic oils, including, besides variously treated soybean acid, blown oleic acid, commercial castor oil, and oils, also linseed, castor, perilla, oiticica, and tung. blown linseed, perilla, and soybean oils by the Castor oil exhibited the characteristic behavior of Ellis and Jones method using a one-hour period of hydroxylated compounds, giving an appreciable reflux. Maleic anhydride values, ranging from 5.2 M. A. V. and diene value which fell to nearly zero in the case of blown oleic acid to 31.4 for di- after acetylation. Tung oil also exhibited a small decrease iii M. A. V. arid diene value after acetylahydroxystearic acid, were observed. This Laboratory has been engaged for some tion. However, the M. A. V. and diene values of months on a study of the applicability of the linseed and soybean oils, which were initially low, Ellis and Jones, and the Kaufmann, Baltes, and rose appreciably after acetylation. In the case of Buter, diene methods, as a means of following these two oils the increase in the diene value (800changes in the polyethelloid linkages of soybean IO00 per cent.) was accompanied by an increase in
Dec., 1937
COMMUNICATIONS TO THE EDITOR
2745
methyl ester of 6-~-glucuronosido-galactosecrystallizes as rosets of needles. The melting point of the pure substance is 201-202' (uncorrected) rCrIz3D +lS-I.i' (c, 1%) (found, Br, 11.52). When the latter derivative is condensed with U. S. REGIONAL SOYBEAN W. G. BICKFORD INDUSTRIAL PRODUCTS LABORATORY F. G. DOLLEAR methyl alcohol in the presence of silver oxide the URBANA,ILLINOIS K. S. MARKLEY methyl ester of hexaacetyl-G-P-glucuronosidoRECEIVED NOVEMBER 23, 1937 methylgalactoside is formed in yields of 60%. The derivative crystallizes as prismatic needles THE SYNTHESIS OF ALDOBIONIDES melting a t 184' (uncorrected) [ a D]' +86.4' Sir : (C, 1%) (found, OCH, 9.96). We have certain Aldobionic acids are disaccharides containing evidence which indicates that the synthetic a uronic acid as one of the sugar constituents. methyl glycoside of the aldobionic acid derivative These sugar acids were found among the products is the a instead of the anticipated p-glycoside. of hydrolysis of the immunologically specific car- HOSPITAL OF THE ROCKEFELLERWALTHER F. GOEBEL E. REEVES INSTITUTE FOR MEDICAL RESEARCH RICHARD bohydrates of certain encapsulated pathogenic NEW YORK,N. Y. ROLLIND. HOTCHKISS microorganisms [M. Heidelberger and W. F. RECEIVED NOVEMBER 20, 1937 Goebel, J. Bid. Chem., 70, 613 (1926); W. F. Goebel, ibid., 74,619 (192i)l; they have since been FREE ROTATION ABOUT CARBON-CARBON BONDS obtained from various plant gums as well. The synthesis of two aldobionic acids, gentiobiuronic Sir: Montgomery, McXteer and Franke [THIS acid and the aldobionic acid of gum acacia, has JOURNAL, 59, 1768 (193i)l find for the reaction been described recently [R. D. Hotchkiss and n-CeHio i-ChHio W. F. Goebel, J . Bid. Chem., 115, 285 (1936)l. The chemical constitution of a third aldobionic an equilibrium constant of about 4.0 in the liquid acid, cellobiuronic acid obtained from the specific phase a t 27'; the corresponding value for the polysaccharide of pneumococcus, Types I11 vapor phase is calculated to be 3.5. This result and VIII, have also been established [R. D. when combined with Rossini's accurate value Hotchkiss and W. F. Goebel, ibid., 121, 195 = - 1630 cal. gives A&,s = -2.08 0.55 (1937)l. e. u. The third law measurements of Parks, ShoSince it is our desire to prepare for chemo- mate, Kennedy and Crawford [J. Chcm. Phys., 5, immunological study, artificial carbohydrate- 359 (19:3i)] gave -5.8 * 1.2 e. u. Statistical protein antigens containing these three aldobionic calculations of Pitzer [ibid., 5,473 (193i)I assumacids, a method for the synthesis of aldobionides ing potential barriers of 3400-3800 cal. opposing has now been developed. The preparation of the free rotation gave -4.3 e. u., as compared with acetobromo derivatives of the methyl esters of -4.1 e. u. calculated by Kassel [ibid., 4, 276 the acacia aldobionic acid (6-p-glucuronosido- (1936)l on the basis of free rotation. Direct exgalactose) and of cellobiuronic acid (4-P-glucu- periment thus shows isobutane to be significantly ronoside-glucose) was achieved in the following more stable than is indicated by any calculation; manner. unpublished work done in this Laboratory supWhen the heptaacetyl methyl ester of cello- ports this conclusion. biuronic acid or of the acacia aldobionic acid, is A major argument against the assumption of allowed to stand in the presence of acetic acid free rotation has been the consistency with which saturated with hydrogen bromide, the a-bromo- statistical entropies based on it exceeded third hexaacetyl methyl ester of the corresponding aldo- law determinations. It now appears, however, bionic acid is in each instance formed. The de- that the difference of the third law values for the rivatives may be isolated from the reaction mix- two butanes is in error by 3.7 e. u. Modern detures in excellent yields. The a-bromohexa- terminations of this sort can only be wrong by acetyl methyl ester of 4-~-glucuronosido-glucose is failure to attain equilibrium in the crystal, and obtained as glistening needles melting a t 200' hence can only be low. The third law value for (uncorrected) [ a I z 4+99.4' ~ in CHC13 (C, 1%) isobutatie must therefore be a t least 3.7 e. u. low, (foutid, Rr, 11.66). 'The a-bromnhexaacetyl and the correct value of StSN is at least 73.7 e. u.
the refractive index, a decrease in the iodine value, and a shortening of the drying time; all of which indicated a shift of the polyethenoid bonds toward a conjugated system.
