SULFONATION OF PHENANTHRENE
a t room temperature overnight. Ether and 5% aqueous hydrochloric acid were added and two layers eeparated. The ether layer was washed with 5% hydrochloric acid, water, 5% sodium bicarbonate, and then with saturated sodium chloride. After removal of the ether, crystallization occurred. Recrystallized twice from alcohol, the compound melted at 122-123'; yield 54%. Anal. Calcd. for C19H180a:C, 66.66; H, 5.30. Found: C, ~-(3,4-Methylenedioxyphenyl)atropic acid, ethyl ester (VIZZ, R = C2HnIwas DreDared as the methvl ester ( d e 66.73; H, 5.14. 8-( 3,4-Methylenedioxyphenyl)tropicacid, methyl ester, proscribed above):-m:u. l O O - ' l O ~ " (lit. 104") recrystallized from pionate ( X , R' = CHs, R" = CzHs), was prepared from VI alcohol; yield 56%: Anal. Calcd. for ClgHle04: C, 72.96; H, 5.44. Found: C, as described except that propionyl chloride was used instead of acetyl chloride; m.p. 82"-83" after recrystallization from 72.80; H, 5.38. ~-(3,4-Methylenedioxyphenyl)tropicacid, silver salt ( V I ) , alcohol; yield 56%. Anal. Calcd. for CzoHzo06: C, 67.40; H, 5.66. Found: C, was prepared as follows: V, 200 g. (0.7 mole), was stirred in water, 1800 ml., a t 5". Concentrated ammonium hydroxide, 67.03; H, 5.60. 80 ml. (0.7 mole) was added until the solution was just p-(3,4-Methylenedioxyphenyl)t~opic a d , ethyl ester, aceneutral to indicator paper. Silver nitrate, 121 g. (0.71 mole) tate ( X , R' = CzH6, R" = C H 3 )was prepared as described was then added slowly and the mixture was kept a t 5" over- above; m.p. 108"-110" after recrystallization from alcohol; night. After filtering, the residue was washed with cold water yield 36y0. and then i t was air-dried in the dark. The product was Anal. Calcd. for CzoH2006: C, 67.40; H, 5.66. Found: C, further dried in vacuo over phosphorus pentoxide. Yield 67.02;H, 5.66. 272 g., or 99% of theory. Acknowledgment. The authors gratefully ac-' ~-(S,4-Methylenedioxyphenyl)tropicacid, methyl ester, acetate ( X , R' and R" = CH3),was prepared from VI. Methyl knowledge the aid of Ray W. Ihndris. All microiodide (0.084 mole) was added dropwise to VI (0.076 mole) analyses were performed by Kathryn Gerdeman, of in 250 ml. of ether with stirring. The mixture was refluxed the Chemistry Department, University of Mary18 hr. and then was filtered. Pyridine, 18 ml., was added to land. the filtrate and while stirring there was added acetyl chloride BELTSVILLE, MD. (0.1 mole). The mixture was refluxed for 4 hr. and then kept
~-(3,4-MethyZenedioxyphenyl)atropic acid, methyl ester
( V I I I , R = C H S ) ,was prepared from V (0.15 mole) by r e fluxing with 3% methanolic hydrogen chloride (200 ml.) for 4 hr.; m.p. 110-11lo (lit. 106-107") recrystallized from alcohol; yield 83%. Anal. Calcd. for CllH1404: C, 72.34; H, 5.00. Found: C, 72.34; H, 4.93.
[CONTRIBUTION FROM THE DEPARTMENT O F CHEMISTRY, FORDHAM UNIVERSITY]
Sulfonation of Phenanthrene by Dioxane- Sulfotrioxide' SISTER MIRIAM GRACE SOLOMON
DOUGLAS J. HENNESSY
Received June 6, 1967 Phenanthrene is converted by dioxane-sulfotrioxide to 1-, 2-, 3- and 9-phenanthrene sulfonic acids. The salts of these isomeric acids are isolated in yields of 5-7%, 4-6%, 27-32010 and 24-30%, rsspectively.
Earlier reports2 on the sulfonation of phenanthrene in which sulfuric acid was used indicated the need for temperatures of 120-125" for a short reaction time. Losses due to polysulfonation and sulfone formation had to be accepted and only the phenanthrene-2- and the phenanthrene-9-sulfonates were isolated. At lower tefnperatures, very long reaction times were needed. The yields were still unsatisfactory although some phenanthrene-1- and phenanthrene-9-sulfonates were isolated. Table I summarizes this earlier work. The fractionation and isolation of the isomers were a long and tedious process especially when all four isomers resulted from the sulfonation. Suter et aL3 have reported facile sulfonation of naphthalene by dioxane-sulfotrioxide. This reagent (1) Presented before the Division of Organic Chemistry, AMERICANCHEMICAL SOCIETY, 130th Meeting, Atlantic City, September 1956. (2) References to earlier reports are given by L. E. Fieser, Org. Syntheses, Coll. Vol. 11, 482 (1943). (3) C. M. Suter, P. B. Evans, and J. M. Kiefer, J . Am. Chem. Soc., 60,538 (1938).
turned out to be well suited for the monosulfonation of phenanthrene. Generally, 94-960/, of the phenanthrene was converted into water soluble material during the sulfonation and over 90% of the water soluble product could be precipitated as an insoluble sodium salt by the addition of a saturated soluTABLE I
Reaction Yields, % of T ~ ~ Time, ~ . , Phenanthrene Sulfonates "C. Hrs. -1-2-3-9120-125 60
Werner' Sanqvistc Ioff ed
120-130 100 20
... 17-21 24-26 4-8
18 12 7
.. . 8 ... 400 ... ... ... ... 17-37 5
19 18.6 9-11
... 4 7-14.6
Cf. Ref. 4. A. Werner, B. Lowenstein, A. Wack, T. Frey, M. Kunz, K. Rekner, A. Ney, H. Heil, A. Scherrer, H. Schwabacher, J. Kunz, and A. Grob, Ann., 321, 248 (1902). H. Sandqvist, Ann., 392. 76 (1912). I. S. Ioffe. J. Cen. Chem. (U.%.S.R.), 3,' 448 (1933), Chem. Abstr., '28, 1694 (1934).
SOLOMON AND HENNEBBY
tion of sodium chloride, indicating that little, if any, polysulfonation had occurred. The isolation of 72-75% combined yield of pure salts of the isomeric monosulfonic acids is additional evidence for the preponderance of monosulfonation. The sulfonation was carried out at various temperatures between 0" and 60" with no significant change in the relative yields of the four isomers. I n order to maintain a high conversion, the reaction time had to be lengthened as the reaction temperature was lowered. These data are summarized in Table 11. The' reported instabilitya of dioxane-sulfotrioxide at 75" limited the highest temperature in this investigation to 60". TABLE I1 SULFONATION OF PHENANTHRENE BY DIOXANESULFOTRIOXIDE Temp,,
30 20 7 5 3
Yields, % of Phenanthrene Sulfonates -1-2-3-95 5 6 6.5 6.5
5 6 5.5 6 4.8
25 30 30 32 32
24 28 29 30 28
In the course of working out the fractionation of the isomers, a rather simple procedure was developed. Three new observations helped in this regard: (a) Sodium phenanthrene-1-sulfonate crystallized in comparatively pure form from an aqueous solution saturated with ether while the other isomers remained in solution. The ether seemed to suppress the crystallization of the other isomeric salts. (b) Most of the potassium phenanthrene-3-sulfonate crystallized at 60" from a solution one-fourth saturated with potassium chloride at 25", while the 2- and 9-isomers remained in solution. (c) Potassium phenanthrene-9-sulfonate was quite soluble in boiling methanol while the 2- and 3-isomers were nearly insoluble in this solvent. Certain features of the Fieser fractionation were combined with the observations staked above t o develop the procedure which we finally adopted for the isolation of the pure isomeric phenanthrene sulfonates. The purity and identity of the isolated sulfonates wae established by the formation of crystalline toluidine salts whose melting points corresponded ciose!y with those reported by F i e ~ e r . ~ 1 ,interesting ~ somparison of the yields of the isomerii sulfonates with reactivities at the five available i-ositions as determined by quantum mechanical methods is represepted in Table IIX. The relative yield of the I-isomer is seen to be less than that predicted from the calculations while the relative yield o+' the 3-isomer is significantly greater than the calculated reactivity would indicate. The ob(4) E. F. Fieser.
Am. Chem. SOC..91, 2480 (1929).
vious steric hindrance at the 4 position almost certainly accounts for the apparent failure of sulfonation at this position. TABLE I11 COMPARISON OF CALCULATED REACTIVITY AT THE FIVE AVAILABLE POSITIONS IN PHENANTHRENE WITH YIELDSOF ISOMERIC PHENANTHRENE SULFONATES
Frontier Electron Density Distribution6
Yields, %of Sulfonates
1 2 3 4 9
0.231 0.004 0.148 0.110 0.344
0.134 0.086 0.079 0.122 0.133
2.30 2.50 2.41 2.39 2.30
6-7 4-6 27-32 0 28-30
Sulfonation of phenanthrene. To a solution of 100 ml. (1.1 mole) of purified dioxane' in 350 ml. of dry ethylene dichloride in an ice-packed %liter, 3-necked flask fitted with a stirrer, condenser, and dropping funnel, there was slowly added from the dropping funnel 88 g. (1.1 mole) of sulfur trioxides while the reaction mixture was stirred vigorously. After the sulfur trioxide had been added, the dropping funnel was removed and 178 g. ( 1 mole) of pure phenanthrene,g m.p. 98", was added to the contents of the flask through a powder funnel. The temperature of the reaction mixture was raised to 50" a t which temperature it was maintained for 5 hr. The same procedure was followed when the reaction was run at temperatures other than 50°, except that the times were changed to those indicated in Table 11. Isolation of the pure salts of the isomeric phenanthrene sub fonic acids. Sodium phenanthrene-I-sulfonate. The sulfonation mixture was extracted with 2.2 liters of cold water. The ethylene dichloride was evaporated. This yielded 6-10 g. of water insoluble material. The supernatant, straw-colored aqueous layer was extracted with 400 ml. of ether, brought to pH 6 with a 10% aqueous solution of sodium hydroxide, cooled to loo, and allowed to stand with occasional agitation a t this temperature for 30 min. A little ether was added to maintain saturation by this solvent. The glistening plates which separated were collected on a Buchner funnel and recrystallized from boiling water to yield 17-20 g. (6-70/,) of sodium phenanthrene-1-sulfonate. The toluidine salt was prepared by dissolving 0.15 g. of the sulfonate in 15 ml. of boiling water with 0.10 g. of p-toluidine hydrochloride. The ( 5 ) K. Fukui, T. Yonezawa, and H. Shingu, J . Chem. Phys., 20,723 (1952). (6) F. H. Burkitt, C. A. Coulson, and H. C. LonguetHiggins, Trans. Faraday SOC.,47, 553 (1951). (7) E. Eigenberger, J . prakt. Chem.  230, 75 (1931). (8) Sulfan B, General Chemical Co. (9) The method of Bachmann [S.Am. Chem. Soc., 57,557 (1935)] was used to purify 90% phenanthrene (Gesellschaft f. Teerverwertung b.H. Duisberg-Meiderich, Germany) after which all colored impurities mere removed by solution of the powdered phenanthrene in petroleum ether and column chromatography of the solution on aluminum oxide (non-alkaline grade, Alupharm Chemicals, 322 Lafayette Street, New Orleans, La.). The effluent from the column was continuously distiild and the distillate was used to dimolve the phenanthrene. The colored impurities were re. alumina and $he snow white phenanthrene was tained o ~the recovere5 in over 90% yield from the continuously concentrating eauent. The melting point was 98".
9,10-DIARYL-9, 10-DIUYDRO-9, 10-PH~NANTHRENEDIOLS
crystalline product separated upon cooling and when recrystallized from boiling water melted a t 265-267'.'0 The toluidine salts of the other isomers were similarly prepared. Potassium phenanthrene-3-sulfonate. The filtrate from which the sodium phenanthrene-l-sulfonate had been separated was heated to go", 800 ml. of a solution of potassium chloride, saturated at 25', added, and the temperature allowed to drop to 60' where it was held for 30 min. The crystalline product was collected on a Buchner funnel and recrystallized from boiling water. The yield was 80-90 g. (27-30%). The toluidine salt melted at 218-219'. Potassium phenanthrene-9-sdfonate. T o the filtrate from which the potassium phenanthrene-3-sulfonate had been separated, there was added 400 ml. Qf a saturated solution of potassium chloride and the mixture refrigerated a t 4' overnight. The precipitate was collected, dried, and digested first with 800 ml., and then with 400 ml. of boiling methanol. The combined methanol extracts were evaporated. The residue dissolved in 1 liter of boiling water was treated with 25 ml. of a 10% solution of barium chloride dihydrate. The mixture was held at the boiling temperature for 10 min. and then filtered on a preheated Buchner funnel. The precipitate which was a small amount of barium phenanthrene-a-sulfonate was retained. The filtrate was treated with 60 ml. of 5M sulfuric acid, digested at the boiling point for 10 min., and filtered to remove barium sulfate. To this filtrate there was added 150 ml. of a 20% solution of hydrated ferrous sulfate in 2% sulfuric acid. After this was allowed to stand in the cold overnight, the greenish crystals which formed were (10) All melting points were taken on a Fisher-Johns melting point apparatus and are uncorrected.
separated and recrystallized from boiling water to which was added a small amount of sulfuric acid and ferrous sulfate solution. The purified ferrous phenanthrene-9-sulfonate was suspended in 200 ml. of boiling water and treated with an equivalent amount of a 20% solution of potassium hydroxide. After digesting a t the boiling point for 15 min. the mixture was filtered to remove iron hydroxide and the filtrate allowed to stand in the refrigerator overnight. The yield of recrystallized salt was 83-89 g. (28-30700). The toluidine salt melted at 230-232'. Sodium phenanthrene-2-sulfrnate. The alcohol-insoluble residue from which the 9-isomer had been extracted was dissolved in 1 liter of boiling water and 100 ml. of a 10% solution of barium chloride dihydrate was added. After digesting the mixture a t the boiling point for 10 min., the barium phenanthrene-2-sulfonate was collected on a hot Buchner funnel and combined with the material obtained during the isolation of the potassium phenanthrene-9-sulfonate. The filtrate upon cooling deposited crystalline flakes of barium phenanthrene-3-sulfonate. The barium salts were separately converted to the free acids by treatment with 5% sulfuric acid. Subsequently the barium sulfate was removed and the respective solutions neutralized with a 25% solution of sodium hydroxide to yield crude sodium phenanthrene2-sulfonate and with 25% solution of potassium hydroxide t o yield 5-7 g. (cat. 2%) of the potassium phenanthrene-3sulfonate. The latter was obtained in.pure form. The 2isomer, purified by recrystallization from boiling water was obtained in yields of 12-18 g. ( 6 6 % ) . The toluidine salt melted a t 283-285'. NEWYORK58, N. Y.
DEPARTMENTO F CHEMISTRY, FORDHAM UNIVERSITY]
Syntheses and Absorption Spectra of cis- and trans-
9,lO-Diaryl-9,lO-dihydr0-9,lO-phenanthrenediols~ EMIL J. MORICONI, FRIEDRICH T. WALLENBERGER, LESTER P. KUHN,S AND WILLIAM E". O'CONNOR
Received May 20, 1967 The syntheses and characterization of a series of cis- and trans-9,10-diaryl-9,10-dihydro-9,lO-phenanthrenediols are described in which the 9,lO-diary1 substituents vary in bulk (aryl = 4-methylphenyl,2,4-dimethylphenyl~2,4,6-trimethylphenyl, 2,3,5,6-tetramethylphenyl,and l-naphthyl). Each cis-trans isomeric pair was configurationally related by oxidation to the same 2,2'-diaroylbiphenyl, and conversion to the same acid-catalyzed rearrangement product. Intramolecular hydrogen bonding measurements of the cis-diol series in the 3 micron region show Av( OH) shifts of 38 cm. --l to 69 cm. -1 I n the trans series, only the trans-di( 1-naphthyl) diol showed any hydrogen bonding [ Av(OH) = 36 cm. -11. These infrared measurements are interpreted in terms of the non-bonded steric effectsof the aryl substituents upon the 0-C-C angles at the 9,lO-positions. A preferred conformation is suggested for the trans-&( l-naphthyl) diol. Interplanar angles of the biphenyl moiety calculated from ultraviolet absorption data show only a slight increase in both the cis- (32-36') and trans-series (30-34').
The molecule of 9,lO-dihydrophenanthrene can in order to accommodate the two methylene groups be regarded as having a collinear biphenyl skele- without appreciable di~tortion.~ ton with a 2,2'-two-carhon-atom bridge. The two As part of a study of cis- and trans-configurations benzene rings are twisted at an angle of about 20" about this two-carbon-atom bridge, we have prepared and characterized a series of cis- and trans9,lO -diaryl-9,10-dihydro - 9,lO phenanthrenediols ( 1 ) Presented in part before the Organic Division of the Meeting-in-Miniature of the New York Section, AMERICAN (11) in which the 9,lO-diary1 substituents vary in CHEMICAL SOCIETY,February 15, 1957, and a t the 132nd bulk. SOCIETY,New York, meeting of the AMERICANCHEMICAL The general methods used in the synthesis and
N. Y., September, 1957. (2) Ballistics Research Laboratory, Aberdeen Proving Ground, Md.
(3) G . H. Beaven, D. M. Hall, M. S. Lesslie, and E. E. Turner, J . Chem. Soc., 854 (1952).