CONDENSATION OF KETONES WITH PHENOLS. PART I. 399XL I V.-- Co”iLdensatioiz of Ketones with Phenols. Part I.Condensation with a- Naphthol. *By HEMENDRA KUMAR SEN-GUPTA,THE condensation of ketones with phenols has already been investi-gated in some cases (Wittenberg, J . p. Chern., 1882, [ii], 26, 76;Dianin, J . Buss. Phys. Chem. SOC., 1891, 23, 488; Fabinyi andSzBki, Ber., 1905, 38, 2307; Zincke and Gaebel, Annnlen, 1912,388, 299), but no special study appears to have been made withreference to the influence exerted by substitmnts in the phenolson this type of condensation; further, the position of the linkingof thO carbonyl carbon with the phenols, particularly naphthols,has not yet been ascertained. The idea of elucidating the latterpoint led to the present investigation, and i t was hoped that by* For abstract, see P., 1913, 29, 29400 SEN-GUPTA : CONDENSATIOS O Foxidising the cmdensation products obtained from ketones anda-naphthol(E>CO + ZC,,H,*O 1 I = 1' ,:>C<Eloz">O + 2H2010 0naphthaxanthones of known constitution could be prepared, whichwould, therefore, settle the question in view.Instead, however, ofyielding a iiaphthaxanthone, the oxidation of the anhydrides of1 : 1-dihydroxydinaphthyldialkylmethanes gave rise t o two seriesof coloured, crystalline substances (P., 1913, 29, 382). The workdirectly bearing on the constitution of these being still in progress,and as final conclusions must depend on cumulative evidence basedon a large number of experiments, i t is proposed t o describe in thefollowing pages some new condensation products of a-naphtholwith ketones that have come t o be studied in this connexion.The only case of condensation of a-naphthol with a ketone thathas hitherto been described, is that with acetone.Dianin (Zoc c i t . )employed fuming hydrochloric acid (D 1.19) as the condensingagent, but in course of the present investigation i t has been foundthat phosphoryl chloride serves the purpose decidedly better. Theyield is subetantially improved, whilst the duration of the experi-ment is very much shor€ened, and the reaction can be conductedin an open vessel. The condensation products are obtained in theform of anhydrides, having the general formulaexcept in the case of cyclohexanone, which, in addition t o theusual type of compound, yields one having probably the constitu-tion * :(compare Zincke and Gaebel, Zoc.c i t . , p. 300). The production of* Schmidlin and Lang (Bor., 1910, 43, 2806) incidentally describe thcpreparation of a compound, C,,H,O, which they obtained by the action of coiicen-trated sulphuric acid on a mixture of a-naphthol and cyclohexanonp, and to whichthey attribute the constitution C H /C10H6)0. Their compound has nearly theI0\C,,H,same tnclting point (232") as that of th9 above siibstnnce (Zoc. cit.), but that i t hasnot the constitutioo assigned by thcm will appear from their aiialysis : '' 0.1183 gaveC0,=0*3636 ; H,O=O.0769 ; C=83.82 ; H=7.22 per cent." The correct nnmhwsfor C,H,O, however, are c'=89*15 ; H=6 28 per cent.It should be noted hcrethat aIthough they found the carbon about 2 per cent. lower than what is requiredby the compound CY2H3202, the percentage of hydrogen obtaiiied by them is inagreementKETONES WITH PHENOLS. PART I. 401this evidently poinix to the intermediate formation of chlorohydrinsin this type of reaction.The readiness with which this condensation takes place depends,in the first place, on the molecular weight of the ketones generally-the smaller the molecular weight, the more c a d y is the con-densation brought about. Exception, however, is met with inthe case of fluorenone, which condenses with a-naphthol as readilyas does acetone, although benzophenone gives a yield of 7 percent. only. Secondly, the nature of the carbon atoms in directunion with the carbonyl group seems to influence the condensation.Thus i t is found t h a t tertiary carbon atoms greatly inhibit it, asis seen in the typical case of camphorquinone, which condensesfairly readily with two molecules of phenol, cresol, or catechol(compare P., 1913, 29, 155), whereas under the same conditionsof experiment camphor itself does not undergo condensation.Thisis probably due, as stated above, to the tertiary carbon atom indirect linking with the carbonyl group of camphor, which, althoughpresent in camphorquinone, is there associated with another car-bony1 group in direct union with a secondary carbon atom.EXPERIMENTAL.The Anhydride of 6-1 : l-D,iA.ydroxydinaphthylpropana,A mixture of 28.8 grams of a-naphthol, 5.8 grams of acetone,and 2-3 C.C.of phosphoryl chloride wm heated a t looo f o r fiveminutes, when a brisk action occurred, a t the end of which theliquid set to a crystalline mms. To ensure complete reactionabout. 1 C.C. of acetone was further added, and the flask heatedanother five minutes. The crystalline mass was digested withalcohol, which dissolved out any unchanged a-naphthol and decom-posed the unchanged phosphoryl chloride, leaving the condensationproduct in a white, crystalline stab. The yield at this stageamounts to about 65 per cent. of the theoretical, and, on recrystal-lisation from alcohol, about 58 per cent. By Dianin’s method,using fuming hydrochloric acid as the condensing reagent, theyield scarcely exceeds 50 per cent. The substance crystallises inlustrous, quadratic plates, melting at 186O (as stated by Dianin).It is sparingly soluble in alcohol, readily so in acetone, chloroform,carbon disulphide, pyridine, or benzene.(Found, C = 89.4 ;H=5.86.The picrate, prepared in benzene solution, crystallises in darkred prisms, melting at 164-165O. It is soluble in most solvents;almost insoluble in ether:Calc. C=89*03; H=5.8 per cent.402 SEN-GUPTA : CONDENSATION OF0.2500 gave 17.4 C.C. N, at 18’5O and 744 mm. N-7.88.C~3H,80,C,H30,N3 requires N = 7.79 per cent.The dichloro-derivative, CHB>C<U10H5C1>0, CH, C,,,H,Ci was prepared bysaturating with dry chlorine a solution of the anhydride in carbontetrachloride.The solid residue left after expelling the solventwas crystallised twice from pyridine diluted with a few drops ofwater. It is very sparingly soluble in alcohol, readily so in carbondisulphide, chloroform, pyridine or acetone, and melts a t 262O :0.2264 gave 0.1680 AgCl. Cl= 18-32.C,,H,,OCI, requires C1= 18-73 per. cent.The diibronio-derivative was prepared by adding the requisitequantity of bromine dissolved in carbon disulphide to the anhydridealso dissolved in the same solvent. When the evolution of hydrogenbromide ceased, the carbon disulphide was expelled, and the residuecrystallised from pyridine diluted with a few drops of water. Itis sparingly soluble in alcohol or acetic acid, but readily so inacetone, carbon disulphide or pyridine.It crystallises in rhombicprisms, melting a t 287--289O :0.3374 gave 0-2675 AgBr. Br = 33.73.C,,H,60Br2 requires Br= 34.1 per cent.grams of the anhydride were suspended in about? 50 C.C. of glacialacetic acid, and the temperature kept below 5O; 3 C.C. of fumingnitric acid were next added drop by drop with constant shaking;towards the latter part of the addition of nitric acid, most ofthe nitro-compound separated from the solution. After allowingthe mixture to remain a t the ordinary temperature for about aquarter of an hour, the yellow precipitate was collected, washedseveral times with alcohol or water, and crystallised from boilingglacial acetic acid, from which it separates in long, yellow needles,melting at 225O. It is sparingly solubIe in almost all solvents,but dissolves readily in hot nitrobenzene or pyridine.It can befurther brominated or chlorinated, whilst the dinitro-derivativedescribed below cannot be further brominated at the ordinarytemperature :0.2615 gave 9.25 C.C. N, a t 16.8O and 746 mm. N=4*1.The Dinitro-derivative.-One part of the anhydride was dissolvedin 12 parts of glacial acetic acid by boiling. The solution wasallowed to cool to 80-90°, and 8 par& of fuming nitric acid wereadded. The mixture was allowed to remain at looo for about anhour. and then poured into water. The dinitro-derivative separ-C,,H,,O,N requires N = 3.94 per centKETONES WITH PHENOLS. PART I. 403abed in an almost theoretical yield. When crystallised from hotnitrobenzene, it is obtained in golden-yellow, prismatic needles,which remain unmelted a t 327O.It is sparingly soluble in theordinary solvents, more readily so in boiling acetone, carbondisulphide or pyridine :0.2758 gave 16.4 C.C. N, at 20° and 763 mm. N = 6-84,C,,H,,O,N, requires N = 7.0 per cent.The Anhydride of j3-1: 1-Dihydroxydinaphthylbutane,Three grams of methyl ethyl ketone and 14.4 grams of a-naphtholwere heated with 2 C.C. of phosphoryl chloride in an open flask forabout half an hour, when the contents solidified to a, crystallinemass. If, however, the phosphoryl chloride is added in excem, themas8 is usually pasty, but, on boiling with alcohol, a white, crystal-line residue is left behind which is almost pure. On crystallisationfrom glacial acetic acid, the compound separates in lustrous,rhombic or prismatic plates, melting a t 154-155O.The yield isabout 65 per cent. The solubility of the compound is analogousto its previous homologue:0.1168 gave 0.3803 CO, and 0.0639 H,O.0.6839, in 10.1244 naphthalene, gave At = - 1.452O. M.W. =C=88*87; H=6.07.330.3.C2,H,0 requires C=88.88; H=6*17 per cent. M.W.=324.The dichtloro-derivative prepared by direct chlorination crystal-lises from pyridine, diluted with a few drops of water, in small,colourless needles, melting at 221O :0.1664 gave 0.1244 AgCl. C1= 18.49.C,,H,,OC1, requires c1= 18.06 per cent.The dibromo-derivative crystallises from pyridine in plates,0.1802 gave 0.1420 AgBr. Br=33.5.The dinitro-derivative crystallises from glacial acetic acid in0.1986 gave 12.0 C.C.N, a t 1 8 O and 742 mm.The p'crate is very soluble in benzene, and crystallises in redmelting a t 250O:C,,H,,OBr, requires Br = 33.2 per cent.golden-yellow, prismatic needles, melting a t 2 62-265O :N=6-93.C24H,805N2 requires N = 6-76 per cent.needles, melting at 142-143O404 YEN-GUPTA : CONDENSATION OFThe Anhydride of y-1 : 1-Di hydroxydinaph t hylpentutze,4.3 Grams of diethyl ketone and 14.4 grams of a-naphthol weredissolved in 35 C.C. of glacial acetic acid, and fuming hydrochIoricacid was added until the precipitation of a-naphthol just began.Tha bottle was heated for about 6 hours a t looo, when crystalsbegan t o appear. The heating was continued for two hours more,and the' product was crystalhed as usual from glacial acetic acid,from which it was obtained in colourless plates, melting a t166-167'.The yield is about 30 per cent. of the theoretical.The alternative preparation by the use of 2-3 C.C. of phosphorylchloride takes about an hour, with a yield amounting to about55 per cent.:0.1261 gave 0.4116 CO, and 0.0736 H,O.C25H22O requires C = 88.75 ; H = 6-58 per cent.The dibromo-derivative crystallises in plates, melting a t 258" :0.3140 gave 0.2333 AgBr. Br=31'6.Cz5H2,0Br, require8 Br = 32.22 per cent.The dichloro-derivative crystallises in prisms, melting a t0.3072 gave 0.2136 AgCl.C,,H,,OCl, requires C1= 17-44 per cent.The dinitro-derivative crystallises from glacial acetic acid or hotnitrobenzene in golden-yellow, prismatic needles, becoming dis-coloured a t 29U0, sintering at 298O, and decomposing and meltingat 301-302':C=88.89; H=6-48.238-239' :C1= 17.19.0-1590 gave 9.5 C.C.N, a t 23O and 769.2 mm. N=6.85.C,5€12005N2 requires N = 6.55 per cent.The ,4nhydride of p-1: 1-Dihydroxydinaphthtylpentane,This compound was prepared by using hydrochloric acid as thecondensing reagent, the yield amounting to 40 per cent. of thetheoretical. The alternative preparation with phosphoryl chloridegave a yield of 62 per cent. It crystallises in plates, melting atC=88.38; H=6*34.162-163' :0.1041 gave 0.3374 CO, and 0.0596 H20.C,,Hz,O requires C = 88.75 ; H = 6.58 per centKETONES WITH PHENOLS. PART I. 405The dichloro-derivative melting a t 178-179O was obtained in0.3134 gave 0.2146 AgCl.C1= 17.03.The dibromo-derivative melts a t 196O :Br = 31.93.The dimitro-deriva.tive crystallism from hot nitrobenzene inyellow, prismatic needles, melting at 260-263O :0.4321 gave 24 C.C. N, at 23O and 768 mm. N=6.32.colourless, rhombic plates :C,,H2,0C12 requires C1= 17-44 per cent.0.1566 gave 0.1175 AgBr.Ck,H,,0Br2 requires Br = 32.22 per cent.Ca5H2,0,N, requires N = 6.55 per cent.The ,-2 nhydride of j3-1 : 1-Dihydroxydinaphthyloctane,CH3>C<C,OH,>O. c, ' { I 3 C,,H,6.4 Grams of methyl hexyl ketone and 14.4 grams of a-naphtholwere heated with 2 C.C. of phosphoryl chloride at looo for one-halfto three-qumters of an hour. The resulting paste was boiled withsmall portions of alcohol to remove any unchanged a-naphthol, andthe residue was boiled with about 30 parts of alcohol and thesolution allowed to cool gradually.As the solution cools, a gummydeposit is observed on the sides of the beaker, when the solution iscarefully decanted into another dry beaker. After several minutes,if the sides of the second beaker are found coated with any gummydeposit, the solution is decanted into a third, and so on, until thefirst appearance of a crystalline solid is noticed. On allowing thesolution now to remain for two to three hours, pure crystals canbe collected, melting at 96-97O, which after recrystallisation fromglacial acetic acid or alcohol, melt a t 99O, Gppearing in well-definedprisms. The yield scarcely exceeds 25 per cent.of the theoretical.The substance is markedly more soluble in alcohol or acetic acidthan its homologues :0.1039 gave 0.3386 CO, and 0.0690 H20. C=88*89; H=7*37.The dichloro-derivative melts at 162O :0.2078 gave 0.1354 AgC1.The dibromo-derivative melh a t 193O and crystallises in rhombic0.1720 gave 0.1231 AgBr. Br = 30.46.C&H,,O requires C=88.42; H=7.36 per cent.C1= 16-12.C,,H2,0C1, requires (3 = 15.81 per cent.plates :C281€260Br, requires Br = 30.88 per cent406 SEN-GUPTA : CONDENSATION OFThe dimitro-derivative crystallises in golden-yellow, prismatic0.2160 gave 11.8 C.C. N, a t 1 8 . 5 O and 754 mm. N=6.28.needles, melting at 228-229O :C28H2605N2 requires N = 5.95 per cent.The Anhydride of a-1 : l-Dihydroxy~inaphthy~ethylb enzene,Four grams of acetophenone and 9 grams of a-naphthol weredissolved in about 4 C.C.of glacial acetic acid, and the liquid wassaturated with dry hydrogen chloride in the cold. The mixturewas then heated in a stoppered bottle f o r six hours at looo, whencrystals began t o appear, and the contents of the bottle soon solidi-fied. On recrystallisation from glacial acetic acid, the substance isobtained in rhombic plates, melting a t 167O. The yield amounts toabout 47 per cent. of the theoretical; using phosphoryl chloride a6the condensing reagent, it rose on on0 occasion t o 60 per cent.:0.1001 gave 0.3324 CO, and 0.05 H,O. C=90*8; €X=5*54.The dibromo-derivative melts a t 279-280° :0.1897 gave 0.1296 AgBr. Br=29*6.The dichloro-derivative crystallises in white needles, melting a t0.1407 gave 0.0919 AgCl.C1= 16.15.C,,H,,0C12 requires C1= 16.1 per cent.The dinitro-derivative becomes red above 250°, and melts at0.1457 gave 8.0 C.C. N, at 1 8 O and 765 mm.C2,H2,0 requires C = 90.32 ; H=5.38 per cent,Cz,H180Brz requires Br = 30.18 per cent.242O :308-309O :N=6*3.C2,H,,0,N2 requires N = 6.05 per cent.The Anhydride of Biphenyl-1 : l-dihydroxydinapht?~ylrnethane,C H >c'<cloII~>o. PhPI1 10 6The condensation between bemophenone and a-naphthol couldnot be appreciably brought about in glacial acetic acid solutionby means of hydrochloric acid, even after heating two days a t looo.With phosphoryl chloride, however, although the condensationproduct is easily obtained pure, the yield is only 7 per cent.of thatrequired by theory.Four grams of benzophenone and 6.3 grams of a-naphthol weremelted together on the water-bath, and 1-14 C.C. of phosphoryKETONES WITH PHENOLS. PART I. 407chloride added. Any excess of the condensing reagent must beavoided, or complicated products, difficult to purify, are produced.After heating for two hours, a dark-coloured, viscid mass isobtained, which is treated with alcohol t o remove the unchangeda-naphthol and benzophenone, leaving about 0.7 gram of thecondensation product. It is best crystallised from a hot solutionin pyridine diluted with a few drops of water, when snow-whiteneedles are obtained, melting at 274-275' (compare Clough, T.,1906, 89, 771) (Found, C=91*09; H=5*15.Calc., C=91*2;H=5*@7 per cent.). It is very sparingly soluble in boiling alcoholor acetic acid, but fairly so in benzene, chloroform, or acetone.The dichloro-derivative crystallises from pyridine in platesmelting a t 302-303O :0.1884 gave 0.1090 AgCl. C1= 14.37.The dibronmderivative sinters at about 309' and melts at0.2012 g.ive 0.1255 AgBr. Br=26'55.C,H,OCl, requires C1= 14.11 per cent.311-312':C33H200Br2 requires Br = 27.02 per cent.The A ?LA y dride of Biph eny 1 ene-1 : 1 -c€ihydroxydinaph th y Em e t hane,Two grams of the ketone and 3-22 grams of a-naphthol were heatedwith 1 C.C. of phoaphoryl chloride for about eight minutes a t 100°,when the liquid set to a mass of crystals. The product was washedwith hot alcohol, when the condensation product was left behindas a colourless, crystalline mass.The yield a t this stage amountedto 3h grams, corresponding with 70 per cent. of the theoretical.When crystallised from pyridine, it was obtained in colourless,prismatic needles, melting at 290' :0.1164 gave 0.3910 CO, and 0.0495 H,O.0.3354, in 10.6283 naphthalene, gave A t = - 0*660°.C=91*49; H=4.72.M.W. =400.1.C33H200 requires C = 91.66 ; H = 4.63 per cent. M.W. = 432.The dirtitro-derivative crystallises from hot nitrobenzene in0-3751 gave 15.8 C.C. N, a t 20' and 763 mm.golden-yellow, prismatic needles, which remain unmelted a t 340° :N=5*16.C33€I,,0,N2 requires N = 5.36 per cent.Condensation of cycloHezanone with a-n'aphthol.Cyclic ketones also condense readily with a-naphthol, althoughsecondary reactions seem considerably to diminish the yield (Bey.408 SEN-GUPTA CONDENSATION O F1896, 29, 1595), in the presence of fuming hydrochloric acid orother such condensing reagents. The purification of the condensa-tion product is therefore often attended with some difficulty.cycZoHexanone itself gives two products with a-naphthol, namely,(I) the normal product, CH,<c~~.U,,:>C<~lO::')O.CH .CH and (2) a10 6compound probably having a constitution represented by theformula :the mechanism of the formation of which has already been discussedI n order to obtain the latter compound, 3 grams of cyclohexanoneand 9 grams of a-naphthol were dissolved in about 25 C.C. of glacialacetic acid, and 15-18 C.C.of fuming hydrochloric acid added.The clear solution soon became turbid on heating a t looo, andminute drops of oil began to separate. The heating was continuedfor about one and a-half hours with frequent shaking, when theoil set almost completely to a crystalline cake. This was treatedwith boiling alcohol, when a snow-white, crystalline mass, weighingabout 24 grams, remained behind. It is best crystallised from asaturated solution in boiling glacial acetic acid, in which it issparingly soluble. On allowing to cool gradually, small, colourless,rectangular plates melting a t 236O are obtained :(loc. cit.).0.1103 gave 0.3454 CO, and 0-0708 H20. C=85*4; H=7'12."x0.2144, in l O * T 2 naphthalene, gave At = -0'336O. M.W. =422.7.C,,H,,O, requires C = 85.71 ; H = 7.14 per cent.M.W. = 448.A mononitro-derivative is obtained by suspending the anhydridein glacial acetic acid, heating to 80°, and adding a slight excess offuming nitric acid. The suspended solid dissolves, and on cooling,small, yellow, prismatic needles appear, melting a t 266-267O :0.2175 gave 5.5 C.C. N, a t 20° and 762 mm. N=2*93.C32'H310nN requires N = 2-84 per cent.The A nlzydr?;de of 1 : 1-Dihydrox ydinaph thylcyclohexane,If instead of heating the mixture of cyclohexanone and a-naphtholin an open vessel, as in the previous case, the same proportionsare heated in a sealed tube for eight to ten hours at 100-105°, a* A second analysis gave C = 85-99 ; H = 7 -15KETONES WITH PHENOLS. PART I. 409viscid, black oil is obtained.This is washed once with cold alcohol,and once or twice with small portions of hot alcohol, which removesa great part of the impurities, leaving the condensaticm productin the form of a brown paste. This is dissolved in a small quantityof ethyl acetate, and left for a day or two, when dark-coloured,prismatic needles appear. These are collected and washed with aminimum quantity of light petroleum, which leaves the crystalsmuch brighter. On crystallising twice from it hot solution inpyridine, diluted with alcohol, colourless, thin prisms or needlaare obtained, melting a t 146O. I n a subsequent preparation, thesolution of the brown paste in ethyl acetate wit9 eown with a fewcrystals from the first crop, when the condensation product separ-ated in the course of a few hours. The yield is extremely poor.From 3 grams of cyclohexanone about 0-3 gram of the condensationproduct was obtained :0.1089 gave 0.3570 CO, and 0.0612 H,O. C=89*39; H=6'24.0.1464, in 7.4984 naphthalene, gave At = - 0'390O. M.W. = 355.4.C,,H,O requires C = 89.15 ; H = 6.28 per cent. M.W. = 350.Condensation of 1-Methylcyclohexan-3-one with a-Naphthol.Two grams of 1-methylcyclohexan-3-one and 4 grams of a-naphtholwere heated with 1 C.C. of phosphoryl chloride for two hours in astoppered bottle a t looo. The paste so obtained was boiled severaltimes with frmh portions of alcohol, until it set into a solid. Itwas then repeatedly crystallised from small portions of acetoneuntil it melted at 164-165O:0.1394 gave 0-4531 CO, and 0.0826 H,O. C=88*66; H= 6.59.It is markedly more soluble in glacial acetic acid than the otherThe dinitro-derivative melts at 282O :0.1355 gave 7-45 C.C. N, a t 20° and 759 mm. N=6*25.Further investigation regarding the oxidation and hydrolyais ofC,,H,O requires C=89-01; H=6-59 per cent.members of the series.C,7H,20,N2 requires N = 6-16 per cent.the products described above is in progrees.I take this opportunity of expressing my thanks to Dre. M. A.Whiteley and M. 0. Forster for their kind encouragement in thiswork.ROYAL COLLRGE OF SCIENCE,S. KENSINGTON, S. W.VOL. cv. E