V O L U M E 2 4 , N O . 6, J U N E 1 9 5 2 It is clear from Table V that the finer-grained fractions of any resin are more efficient than the coarser fractions, and that the unsieved resins differ considerably from each other. Fractions sieved between the same limits from various resins are also different. There is (as one would expect) a correlation between the capacity of a resin and its efficiency in separations. This is particularly noticeable in the 80- to 120-mesh fractions, where resin 1 is best and 5 poorest. The poor behavior of unsieved resin 1 is probably due to the fact that its average particle size is larger than that of the others. The fact that only resin 1yielded enough of the 20-40 fraction to give a 40-cm. column supports this hypothesis. On the other hand, the poor behavior of the 40- to 80-mesh fraction of this resin is anomalous. Because resin 1 was distinctly superior to the others in regard to the SO- to 120-mesh fraction, it was believed that the fraction of this resin that passed through the 120-mesh sieve would be the most efficient for the separation of lithium from sodium. In order to get sufficient of this fraction for an elution, the 80- to 120mesh fraction was forced through the 120-mesh sieve by gentle pressure with the thumb. This fraction was then used in Procedure B and gave quantitative separations of lithium from sodium. The similar fraction of resin 2 gave incomplete separations of lithium from sodium under the same conditions. It is unfortunate that various batches of Colloidal Dowex 50 differ from each other. Because of this fact, quantitative separations of the alkali metals performed with a different batch of Colloidal Dowex 50 may, on the one hand, require a longer column or a smaller flow rate or, on the other hand, permit a shorter column or larger flow rate than those specified in this paper. In either case, the fractions of eluate within which any one cation will be contained will probably differ from those given in this paper. If a flame photometer is not available for the analysis of small fractions of the eluate, a simple flame test with a platinum wire and Bunsen burner suffices to indicate the beginning and end of the fraction containing any given alkali metal. Spherical Dowex 50 varies less from batch to batch than the colloidal product ( I ) , but it is less efficient for chromatographic separations. Elution Graphs of Cadmium. Figure 2 ie a typical elution graph of cadmium for the conditions of Procedure B. The unusual feature of this graph is the occurrence of two peaks. Even under the lesa effective conditions of Procedure -4,the graphs of cadmium always exhibited two peaks, but with an intervening minimum that did not extend to zero concentration. Time was
955 not available for investigating the cause of this unexpected phenomenon. I t may be due to a separation of the isotopes of cadmium. SUMMARY AND CONCLUSIONS
Methods are described for the determination of lithium, sodium, and potassium in insoluble silicates by ion-exchange chromatography. Once the behavior of any particular ion-exchange column has been ascertained, these methods require much lee9 time than the classical methods. With two columns in operation, an analyst can perform duplicate determinations of the three alkali metals in an insoluble silicate in one day and still have considerable free time during evaporation and elution. It is helieved that the ion-exchange methods are a t least as accurate as the classical methods. Flame-photometric methods are less time-consuming than ion-exchange procedures, but are less accurate unless the sample contains only a very small percentage of alkali metal. The effect of variations in the elution conditions upon the parameters of the elution equation has been discussed. Colloidal Dowex 50 exhibits appreciably different properties from batch to batch. The fractions with finer particles are more efficient for chromatographic separations. ACKNOWLEDGMENT
The authors express their gratitude to the Office of Saval Research for financial support of this investigation and to IT. C. Bauman for providing some of the samples of Colloidal Dowes 50. LITERATURE CITED
(1) Bauman, W.C., private communication. (2) Bersworth Chemical Co., Framingham, Mass., Tech. Bull. 2
(1951). (3) Beukenkamp, J., and Rieman, W., ANAL.CHEM., 22, 582 (19513). (4) Brown, W. E., doctor’s thesis, Rutgere University, 1950. (5) Flaschkrt, H., 2.anal. Chem., 1 2 9 , 3 2 6 (1949).
(6) Hoffman, J. I., private communication. (7) Loblowitz, W., private communication. (8) Rieman, W., and Lindenbaum, S., ANAL.CHEM., in press. (9) Schwarzenbach, G., and Biedermann, W..H e h . Chun. Acta, 31,678 (1948).
(10) Sweet, R. C., doctor’s thesis, Rutgers University, 1951. (11) Tompkins, E. R., Harris, D. H., and Khym, J. S . , J . A m . Chem. SOC.,7 1 , 2 5 0 4 (1949).
RECEIVED for review January 22, 1952. Accepted April 19, 1952.
Separation and Identification of Polymethylol Phenols by Paper Chromatography J . H. FREEMAN, Westinghouse Research Laboratories, East Pittsburgh, Pa.
T
HE precise identification of the products formed xhen phenol condenses with formaldehyde has long remained a difficult and fundamental problem for both the theoretical and the practical resin chemist. The initial products of the condensation in both acid and alkaline medium are generally conceded to be the hydroxybenzyl alcohols, commonly called methylolphenols (8, 9, 13, 22, 23). For obvious reasons most workers in this field have dealt almost exclusively with methylol derivatives of phenols, in which the reactivity is considerably reduced by substituents in one or more of the three reactive positions of the phenolic nucleus. By this means the number of possible methylol products and higher condensates is drastically curtailed. Similarly, the niethylol
analysis of these compounds and analogous resins has, until non-, been restricted to determination of total average methylol content aithout regard for the number or position of the methylol groups on the nucleus. If are to follow unequivocally the Qtepwise processes involved in resin formation, it is essential that trireactive phenol, which forms the basis for the majority of commercial resins, he studied, and that the initial condensation products of this substance with formaldehyde be individually identified and determined. Such an analysis has not hitherto been feasible. Until very recently only the ortho and para monomethylols of phenol were known. The existence of the 2,4-dimethyloland 2,4,6-trimethylolphenols\vas demonstrated by isolation of
ANALYTICAL CHEMISTRY
956 corresponding a d (!erivatives after oxidation ( d o ) , and certain other derivatives of the trimethylol had been obtained ( 3 , 18). The exiptence of 2,Gdimethylolphenol remained in doubt (20). All three of these polymethylols of phenol have now been synthesized hy the author (10). The synthesis of 2,4,G-trimethylolphenol, recent'ly described by Carpenter and Hunter ( d ) , was independent,ly achieved here by another method and confirms their identification of the substance. The ext#remereactivity of the methylolphenols, t,heir strong tendency to he converted into higher condensation products of a resinous nature, t h e complexity of the niisture (five possible isologous methylols plus unreacted phenol represent theminimum number ofsutwtances which we must attempt to separate), and the ariticipatetl very close similarity in properties of all these conipounds, have been major obstacles in the pathway of a successful critical analysis of such mixtures. In recent yeare t'he technique of paper chromatography has proved itself repeatedly in the analysis of extremely complex systems (6, 6, 11, 16, 2 1 ) . It is a sensitive tool which utilizes very small differences between closely related or even isomeric substances to effect a separation of individuals under the mildest possible conditions. Thus it is almost ideally suited to the problem under consideration. The analysis of catalyzed mi\-tures of phenol and formaldehyde and the identification of the various initial products become possihle a t any desired point simply by withdrawal of a sample and without resort to heating, estraction, chemical reartion, preparation and separation of derivatives from the mixture, or other common laboratory procedures. The method provides for direct' analysis of the mixture a h i t is at any given moment and includes t,he added advantagw oi high sensitivity, very simple apparatus, and rather easy intcrpwtation of results. Xs chromatograms can he run overnight, the analysis is not particularly demanding of the chemist's timr. \Vhen a chromatogram is made of a mixt'ure of phenol and formaldehyde catalyzed by sodium hj-droxide, seven distinct spots are found. Individual colors and Rf values are included in Table I. The first six of these were assigned identities in order of decreasing R, values as phenol, saligenin, p-hydrosybenzyl alcohol, 2,Ci-dimet hylolphenol, 2,4-dimethylolpheno1, and 2,4,6-trimethylolphenol on the basis indicated in Table I. From the work of Ziegler and Zigeuner (24)it \vas knonn that diazonium compounds (used as the indicator) will couple uith methylolphenols a t the rate of one azo coupling per phenolic nucleus, that the coupling \Till occur in the para in preference to the ortho position, and t'hat the methylol group will be replaced in preference to ring hydrogen atoms. Thus v-e may predict that phenol and phydroxybenzyl alcohol will yield the same azo derivative. This prediction is supported by the fact that the spots corresponding to these known compounds are both red. Iikewise saligenin and 2,4-dimethylolphenol should and do yield ident,ical lavender colors. I n similar manner, both 2,Gtlimethylofphenol and 2,-1,6-trixneth~lolphenolyield blue spots.
OH
OH
6
HOCH2$HzOH
6 H & H
CH*OH CHzOH Diazonium Coupling Reaction I
I
I
IIydroxybenzyl alcohols, commonly called methylolphenols, are now widely believed to be the immediate product formed in the initial reaction of phenol with formaldehyde. However, no method exists by which the five possible individual mono-, di-, and trimethylol compounds may be determined. Paper chromatography now provides a specific and highly sensitive technique by which each of these substances may be separated and identified. The presence of 2,4,6-trimethylolphenol, 2,4-dimethylolphenol, and 2,6-dimethylolphenol as w-ell as p-hydroxybenzyl alcohol, saligenin, and residual phenol in an alkali-catalyzed mixture of phenol and formaldehyde has now been clearly demonstrated. -4bsence of mmethylolphenol and 3,3',5,5'-tetra(hydroxymethyl)-4,4'-dihydroxydiphenylmethane can be simultaneously detected. A s methylol formation is the first step in the phenolic resinification process, the presence or absence of a specific compound or isomer in the mixture may be of considerable importance in influencing the subsequent course of the reaction. A simple, easily conducted, and unambiguous method for tracing the existence of such isomers is now provided. It is conducted directly on the reaction mixture at any stage and requires no physical or chemical change in the system under investigation. The new technique should prove of considerable value to workersengaged in the study of both theoretical and practical aspects of the phenolic resinification process.
Subsequent synthesis of these unknown met.hylo1 compounds showed each to yield it spot' corresponding perfectly in color anti X,value to the identities assigned. The bronn seventh spot only slightly moved from its original position was found to be due to sodium hl-droxide used as catalyst in the condensation reaction. Figure 1 shows a chromatograni of a pure synthetir sample of each member of the meth-lol serips derived from phenol, together with a synthetic mixture of all these components and, in parallel, an unknown mixture of phenol and formaldehyde now shown to contain each of the several possible methylol compounds. In addition, there is displayed a compound (1'11) which has heretofore frequently been presumed to be present instead of the 2,6-dior 2,-1,6-trimethyIolphenols, and finally a tetranuclear molecule of the novolak type. From the relative order of the spots on the chromatogram it appears that, the differentially retarding factor among the coinpouiid~is the number of niethylol groups and the position of the methylol groiip on the ring. The retardiug effect for methylol groups is 3 > 2 > OF1 1 > none and para > inet,a > ortho > none. The reduced -effectiveness of a methylol group in ortho position as compared t o a para group may be ascribed to internal hvCH2OH drogen bonding. Any effect due to the I phenolic hydroxyl group is presumably present in all components. Preliminary studies of the cresols, their methylol derivatives, and methylene bridged structures containing two, three, and four HOCH? C H,OH phenolic nuclei per molecule indicate that cresols and compounds of the Novolak chain structure chromatograph much as does free R phenol, n-hile methylol derivatives of these Blue strurtures have decreasing R, values correh
6 6 66HzoH R = 0 2 S c I ) S =S-
.1
(J
R
R
Red Lavender
R Red
c
J.
CH,OH
HoCHz(JL20H R Blue
R
Lavender
V O L U M E 24, N O , 6, J U N E 1 9 5 2
957
Table 1. Methyl& of I Compound NO.
Formrila
0 0-
M.P., 0
c.
42
Color of
spot
Red
RP
CO~PO\I
No.
IV
0.93
v
,. OH
86
Larender
v
0.84
OH
I11
CHzOH
92
Lnvender
0.61
cnlon
122
Red
CHqOH
0.79
* Rf determined in 4 to 1 I-Butanol-00noentrated ~mmoniumhydroxide s t 2 l 0 C. Values reme.ent average of several runs and are r e p d u o i b l e to *0.01. Spots are sdequstely 8epamted in this system if the differenre /n RI value. is 0.04 or neater. b Compound I1 not found in phenol-formaldehyde mixtures.
spondirig roughly to the ratio of methylol groups per phenolic nucleus (Tahle 11). Figure 2 illustrates a chromatogram of the several 315, polynuclear Novolak models, and some hylol derivatives of these substances. ,matographic separation of these comllYY.idswould not he possible under the eonditions described except in theeaseof themethylol derivatives. The m-monomethplol of phenol is not shown in the photographs. This compound, as indicated hy its R, value in Tahle I, is located on the strip almost precisely midway between the spots representing t.he 0- and p - isomers and gives a recognimhly different color from either of them. If all three isomers are present in 8. mixture, they are not separated within the limits of time and solvent flow employed, but give a large elongated spot. The clear-cut separation of the 0- and pmonomethylols achieved in the phenol-formaldehyde mixture studied is due to, and indicative of, the absence of any of the meta isomer APPARATUS
The chromatographic apparatus is shown in Figure 3. Thq chamber consisted of. l?rpe b a t t e q jar (la inches in diameter and 24 inches high) covered by a piece of Micarta (phenolic laminated board) which was cut in half and machined t o make a perfect joint at the saw cut. Either half of the lid could thus be removed without disturbing the other, permitting two separate strips to be run simultaneously. Aluminum supports were provided for suspending a solvent trough from a c h half of the lid independently. The troughs were made of 9- t o l s i n c h sect,ions of glass tubing 38 nun. in diameter sealed wit.h ffat end8 and then sawed longitudinally. A hole for access of a funnel for addition of solvent wm provided in the t a p above each trough. The end of the paper strip was held in t,he solvent trough by laying a glass rod lengthwise of the trough 80108s the end of the strip. A Petri dish containing some of t.he chromatographic solvent was kept in the bottom of the jar at. all times to maintain a saturated atmosphere. The top ~~~
Figure 2. 1. 2.
Phenol o-Fl~droaybenzylalcohol (Sslicenin)
to 6, inclurive Sodium hydroxide-catdysed mixture of Dhenol and formaldehyde sam le taken after 11 days) 9. 3.d',5.57-Tetra (hydrorymethyl) 4.4'dih drorydiphenylrnethane (VI11 10. 2,4.6-~ri(Z'.hyd~~~y-5'mPthyibenzyl) phenol (XVII) 8.
Chromatograms
ethyl) 4,4'hanc (VII) orymethylmethane
9. a-Cre.01 2.4-dimethylal (XII) IO. o-Creso1 (XI) 11. m-Cresol (XIV)
9.58
ANALYTICAL CHEMISTRY
edge of the jar, on which the cover rested, was covered by a gasket made from a piece of rubber tubing slit lengthwise. During chromatographic runs the joint between the two lid sections, and the funnel access holes, u-ere kept sealed by cellophane t a e and a weight x a s placed on the lid to maintain pressure on tRe rubber gasket. All chromatograms were made by downivard flow of solvent, except that preliminary tests of various solvents were carried out by capillary ascent.
Table 11.
Compounds Related to Methylol Phenols
Compound
XP.,
HOCHz
VI1
RI
CHzOH
144 H O C H z C S > O H HOCHz CHzOH
Blue
0 48
3 OHzoH
PAPER
The paper used consisted of 9 X 22 inch strips cut from large sheets of Whatman S o . 1 filter paper. Strips were cut and all chromatograms %ere run in the direction parallel to the machine grain of the aper Attempts to run the chromatogram acioss the grain of e!t paper resulted in distinctly inferior and irregular Epots. The original spots were placed a t 0.75-inch (19-mm.) intervals along a line of pencil dots sufficiently below the edge of the paper to clear the lip of the trough and be eluted by the solvent descending along a straight front. [8bout 2.25 inches (6 cm.) was sufficient.]
Color of Spot
c.
Formula
NO.
VI11
Lalendera
0 92
104
Blue
0 89
129
Blue
0
30
Larender
0.93
93
Violet
0 79
135
1 iolet
0 93
La\ender
0 94
Violeta
0.94
Brown
0 03
33
CH3
IX
CHz
SOLVENT
X
The solvent consisted of a mixture of C.P. 1-butanol and concentrated ammonium hydroxide (29% "3) in the proportions 4 to 1 by volume. This ratio was found best for optimum separation of the spots.
0
HOCH?
CHzOH
sz
CHa
OHa H8c5:....i
INDICATOR XI
The indicator reagent was p-nitrobenzenediazonium fluoroborate (16). For the preparation, 0.1 mole (14 grams) of pnitroaniline (Eimer and Amend) was dissolved by heating with 30 nil. of concentrated hydrochloric acid and 30 ml. of water. It was then cooled to 5" C. and a solution of 8 grams of sodium nitrite in 20 ml. of water was added a t once, Sixty milliliters of 40% fluoroboric acid (Baker and Adamson) Mas added, and the fluffy yellow precipitate was separated by filtration, washed successively with fluoroboric acid, alcohol, and ether, and dried in a vacuum desiccator. I n order to permit rapid drying of the strip and reduce diffusion of the spots, a 1 % solution of the reagent in acetone, rather than water, was employed. The reagent is stable in the solid state but the solution is not and must be pre ared fresh daily. After P i n t i n g with the diazonium solution,e!t strips were air dried riefly and then painted nith a 0.1 S solution of potassium hydroxide in methanol, causing the colored spots to appear. The t n o indicator solutions were applipd by aintin the dry strip with separate 3-inch paint brushes, ea,: of mkch had been thinned down to somewhat less than half the normal number of bristles.
XI1
CHpOH
XI11
H o H a c H z d i H HOCH2
CHJOH
XIV
11
o C H 3
XV
CHROMATOGR4PHIC PROCEDURE
The chromatographic chamber was set up, about 100 nil. of solvent mixture was placed in the Petri dish in the bottom, and the system %asclosed and allowed to equilibrate for 4 to 6 hours. The top was then opened briefly, the paper strip and trough R ere inserted, and the system was sealed and allowed to stand 15 to 20 minutes to regain equilibrium. Solvent mixture was added to the trough via the funnel, which was then removed, and the access hole mas sealed by cellophane tape. The chromatogram was a l l o ~ e dto develop for 15 to 16 hours (most runs were made overnight). Just before the advancing solvent front reached the edge of the paper the cylinder was opened, the paper strip removed, and the limit of the solvent front marked with a pencil. The strip was then dried by inserting it in a blower type oven a t 50' to 60" C. for not more than 2 minutes. (Longer drying causes loss of the phenol spot by evaporation.) Spots were located by painting successively a i t h the indicator solutions. On first appearance the spots were brightly colored and clearly distinguishable. For purposes of record they were outlined with a pencil and the colors recorded as soon as the strip was dry; on standing, the background darkened and the spots tended to fade to a uniform color. Rf values were determined by measuring the distance from starting position to the most advanced edge of a given spot and dividing by the distance from starting line to solvent front. Original spots were placed on the paper by means of a selffilling micro pipet of 1-microliter capacity obtained from the Microchemica Specialties Co., Berkeley, Calif. Methanol solutions of the various compounds containing 20 t o 25 micrograms of substance per microliter of solution n-ere employed. By careful repeated application of the tip of the pipet t o the aper, it was possible to deliver 1 microliter of the solution to t l e paper in such a way that the original s ot did not exceed 2 mm. in diameter, I n order that all conchions should be as constant
XVI
214
CHa
CH3
CH3.
XVII
H3C XVIII
SaOH
These spots fade very quickly, generally becoming a tan color when strip is dry. a
atid reproducil)le as posible, tlic chromatogrshls \rere carried OUI
in
:i
constant temperature room n1aint:tined
at
21-22' C.
COMPOUNDS STUDIED
All melting points are corrected. Phenol, Mallinckrodt Co., analytical reagent grade. I. Saligenin, Eastman Kodak Co., recrystallized successively from Eater and benzene. Melting point 86" C .
Y O L U M E 24, NO. 6, J U N E 1 9 5 2
959
11. m-Hydroxyhenzyl Alcohol, obtained by reduction of the 'ester of m-hydroxybenzoic acid (Eastman Kodak Co.). Re-
erystalliaed from benzene. Melting point 73" C. Melting point reported 73" C. (2). 111. PHydroxybenzyl Alcohol, prepared by reduction of Eastman Kadak Co. ~ - h v d r o x v b e n z ~ l"~~~ d ~ h v dReervst~nllin~d ~ . _. from benzene containing ethyl afcohol or from ethylene chloride. Melting paint 109' C. taken by standard method. 122' C. b y insertion in a preheated bath. Reported melting boint 124" C. ~~~~~
~
(7).
pared from 2,4,6tri (acetoxymethyl) phenylacetate (3,18) and p-cresol according to Carpenter and Hunter (4). Yield 67%. Recrystallized from benzene plus xylene. Melting point 184185' C . Melting point reported 185-187" C. PHENOL-FORMALDEHYDE REALTION MIXTURE
The mixture studied consisted of 9.4 grama (0.1 mole) ofphenol, 4.8 grams (0.12 mole) of sodium hydroxide, 10 ml. of water, and 11.4 grams (0.14 mole) of formaldehyde. The mixture was placed in a stoppered flask for several days, and I-ml. samples were withdrawn daily and diluted to 15 ml. with methanol. Repeated chromatograms of these solutions indicated that no noticeable change in composition occurred on standinding several weeks after the dilution. The samples reported in this paper were taken from the mixture after 11 days, when the reaction appeared to have reached a state of equilibrium. Application of I-microliter quantities of this solution to the chromatogram strip sufficed to identify clearly all components of the mixture except phenol and 2,6-dimethylolphenol. For identification of these two substances 2-microliter quantities of the mixture were delivered to the paper. Because of diffusion due to the fact that it travels farthest of d l the spots, and because of its volatility during the drying of the strip, phenol yields a Spot which is only about one third as sensitive as the other compounds. The 2,6-dimethylolphenol a180 yields a faint spot, apparently due solely to it,s occurrence in extremely low concentration in the mixture. The synthetic compound gives a very intense spot. It was further noted that the appearance of the 2,6-dimethylol compound could not be detected until after the reaction mixture had stood for some time. The absence in the mixture of any 3,3'5,5'-tetramethylol4,4'-dihydronydiphenylmethane (VII) or compounds of the "ditan" structure wits also of interest. ACKNOWLEDGMEN?
The author is grateful to G. R. Sprengling of this laboratory for several of the compounds listed in Table I1 and for many helpful suggestions. Figure 3.
Chromatographic Apparatus
IV. 2,6-Dimethylolphenol, melting point 95' C. V. 2,4-Dimethylolphenol, melting point 92' C. VI. 2,4.6-Trime~hy??lphenol,melting point 75" C. Melting
LITERATURE CITED
(1) Auwers. K. v., Ber., 40, 2531 (1907). (2)Beilstein, "Handbuch der organischen Chemie." 4th ed.. Vol. 6, P. 896 (881)'. (3) Bruson, H.A,, and MaoMullen, C. W.. J . Am. C h a . Soc.. 63. 270 (1941). (4) Carpenter, A. T..a d Hunter, R. F., J . Applied Chhem., 1. 217 26 (1951). (5) Clegg. D. L.. ANALCHEM.,22,48 (1' 950). ( 6 ) Consden. R., Nature, 162,359 (1948). T * _ Ynl_0"E C (7) Dunning, B.. Dunning. F., and Reid, 77 #. -IIo_ llmb. YYL., d, 1567 (1936). (8) Euler. H. Y., and Kiswcay. S., Z. physik. C h m . . A189, 109 (1941). (9) Fiehmenn, J. B., J . Am. Chem. Soc., 42, 2288 (1920).
-
-.,
Meltingboint reportid 145" C. (18, 19, 65). VIII. +Cresol, Eastman Kodsk Go., used as received. IX. $-Cresol Monomethylol, prepared by method of v. Auwers ( 1 ) . Melting point 104' C. Melting point reported ,nco _"Y
c ".
X. 2,6-Dimethylol, p-cresol prepared according to van Auwers (1). Melting point 129' C. Melting point reported I 9 n O
IO"
, ".-
XI. *Cresol, Reilly Tar and Chemicai Go., used as received. XII. 2,4-Dimethylol, c-cresol prepared by method of Hanus ( l a ) . Recrystallized from chloroform. Melting point 93.5" C. Melting point reported 94" C. XIII. 3,3'-Dimethyl-5,5'-dihydroxymethyi 4,4'-dihydroxydiphenylmethane, prepared according to Hanus ( l a ) . Melting point 155' C. Melting point reported 155" C. XIV. m-Cresol, Reilly Tar and Chemical Co., purified. Melting point 11' C. XV. S,S'-Dirnethyl-2,2'-dihydroxydiphenyImethane, from p cresol by method of Koebner (14). Melting point 125" C. Melting point reported 126" C . XVI. 4-Methyl-2,6-his (2'-hydroxy-5'-rnethyIhenzyl) phenol, from peresol by method of Koebner (14). Recrystallized 8uccessively from xylene, acetic acid, xylene. Melting point 214" C. Melting point reported 215' C. XVII. 2,4,6-Tri (2'-hydroxy 5'-methylbenzyl) phenol, pre-
(IO) Freeman, J. H., unpublished data. (11) Gordon, Martin, and Synge, Biochm. J., 38, 65 (1944). (12) Hanus, F.,J . prakl. Chem.. 155,329 (1940). (13) Jones, T.T.,J . Soc. Chem. Id.. 65,264 (1946). (14) Koebner, M.,A w w . C h a . , 46, 252 (1933). (15) LeRosen, Moneghan, Rivet. Smith, and Suter, ANAL.CHEX., 22, 809 (1950). (16) Martin, A. J. P., Ann. Repts. Promass Chem.. 45, 267 (1948). (17) Martin, R. W.,ANAL.CHEM.,23, 883 (1951). (18) Martin, R. W.,J . Am. C h a . Sac., 73, 3952 (1951). (19) Seebaoh, F., B e . , 73, 1338 (1940). (20) Sprengling, G. R..and Freeman, J. H.. I . Am. Chem. Soc.. 72 1982 (1950). (21) Strain, H. H..ANAL.CHEM.,23,33 (1951). (22) Ziegler, E.,and Liidde, H., Monatsh., 79, 55 (1948). (23)Ziegler, E., and Simmler, J., Be.,74, 1871 (1941). (24) Ziegler, E.,m d Zigeuner, G.,Monatsh.. 79, 358 (1948). (25)Zinke, A., and Hanus, F.. B e . , 74, 212 (1941). Reomvsn for review February 8, 1952. Accepted March 30. 1952. Presented before the Division of Paint. Varnish, and Plastim Chemistry at the 121st Meeting of the A n r ~ n r o mC x e x r o ~ rSOCIETY. . Milwaukee, Wis. Westinghome Scientific P a ~ e r1637.
