INTERACTION OF BENZOIN WITE PHENY LENEDIAMINES. 1043 CIII.-Intemction of Benzoin with Phenylenediamines. By FRANCIS R. JAPP, F.R.S., and ANDREW N. RIELD~ubi, B.Sc. BY heating benzoin with aniline and a little aniline hydrochloride, Ja,pp and Murray (Trans., 1894, 65, SSZ) obtained 3’ : S’-diphenyl- indole. The desylanilide, C,H,*CO*CH(NH* C6H,)*C!,H,, which is formed in the first instance, and which is the sole product if aniline alone is used, parts with water under the influence of the hydrochloric acid, yielding the indole. We have now studied this reaction with the phenylenediamines, in order, if possible, to obtain the corresponding benzodipyrrhole deri- vatives ; but only in the case of metaphenylenediamine did the reaction take place in the desired sense. 1 . Benzoin and Ort I ~ o ~ ~ ~ ~ e n ~ / l e p ~ e d .i t ~ ) ~ i ~ n e . By heating benzoin with orthophenylenedismine hydrochloride, phenylbenximidaxole hydrochloride, C,H,<?Z>C* C,H,, HCl, mas ob- tained, the benzoin molecule breaking up in the process. The free phenylbenzimidaxole melted at 285’ (instead of 29 lo).1044 JAPP AND MELDRUM: INTERACTION OF Benzoin and free orthophenylenediamine, on the other hand, yielded C H <Ni7:C6H5 diphenylquinoxdine, 6 N.C , oxidation taking place during 6 5 the process. The formation of the latter compound in this reaction had, as we afterwards found, been already observed by 0, Fischer (Ber., 1891, 24, 720). 2. Bennzoin and 2llet~~~~~iz?lle~zediarltine. Ten grams of metaphenylenediamine hydrochloride were dissolved in water, and the base was liberated by caustic soda and extracted with ether.The ethereal solution was dried with potassium carbonate and the ether distilled off. To the base thus obtained 23 grams of benzoin mere added, and the mixture was heated to 180". No reaction occurred ; but on adding a little metaphenylenediamine hydrochloride, there mas a vigorous effervescence ; water mas given off, and the mass solidified in spite of the high temperature. By extracting the melt with boiling alcohol and recrgstnllising the residue from solvent naphtha, the new compound was obtained in slender needles melting at 282". It is almost insoluble in alcohol and benzene, .soluble in chloroform. Dilute acids do not dissolve i t ; but it is soluble in con- centrated sulphuric acid, giving a faint red solution with a greenish fluorescence.Analysis gave figures agreeing with the formula of a nzetnbenzo- 0.1806 gave 0.5858 CO, and 0.0571 H,O. 0.2604 ,, 13.1 C.C. moist nitrogen at 14Oand 751 mm. N= 5*85, c'= 85.46 ; H = 5.36. C,,H24N, requires C = 88.70 ; H = 5-22 ; N = 6.09 per cent. Two constitutions are possible for this conipound, axid at present there is apparently no means of deciding between them. The same compound may be obtained by beating together benzoin and metaphenylenediamine hydrochloride, thus obviating the necessity of preparing the free base ; but the yield is bad, and the substance difficult to purify. 3. Benzoin mzcl Payapheng Zenedictntine. The only method that yielded a definite product was that described in the case of the meta-compound: namely, of heating together benzoin and the free base, and adding a little of the hydrochloride.Twelve grams of psraphenylenediamine hydrochloride were taken ; the base was liberated and extracted with ether, of which a largeBENZOIN WITH PHENYLENEDIAMINES. 1045 quantity was required on account OF the sparing solubility of the para-compound. The base which remained after distilling off the ether was heated along with 23 grams of benzoin until the whole melted. No action took place; but on gradually adding 3 grams of paraphenylene- diamine hydrochloride, the fused mass became pasty and ultimately solidified. The reaction was not so vigorous as in the case of the meta- compound, and less water was given off. The product was boiled with alcohol, and the undissolved portion, which was yellow, was washed with boiling water, dried, and recrystallised from benzene.It was obtained pure by a single crystallisation, and formed bright yellow, minute laminae which, when heated, showed signs of softening about 230°, and melted completely at 257". Analysis pointed to the formula C3,H,,N,0,. 0.1846 gave 0.5588 CO, and 0.0954 H,O. 0*2144 ,, 10.4 C.C. moist nitrogen at 13.5" and 743 mm. N = 5.62. C = 83.55 ; H = 5.74. C:,,H,sN,O, requires C = 83.36 ; H = 5-64 ; N = 5.64 per cent. The compound is formed according to the equation CH(OH)*C,IE, = c: b ,134[NH*yH*C,H,] C,H,(NH1), + 3 CO I C,H, CO. UGHc, ., + 2H,*, Paraplieiiyleiiediainiiie. and may receive the name clic2esyll,ccl.c~2~7~~~~~enecliaq~~i~~e. It corre- sponds with desylmilide (anilbenzoin) and the other compounds ob- tained by Voigt by heating benzoin with primary benzenoid amines (compare Trans., 1S94, 65, 890).DiacetpZ De.l.ivcctive. -Two grams of the foregoing compound were boiled with excess of acetic anhydride for 10 minutes. The solution, which was light red a t first and afterwards becamo darker, mas allowed to cool, and ether was added. A white, crystalline substance separated, which was recrystallised from czmylic alcohol, and was thus obtained in colourless, slender needles melting at 87 9". Analysis gave figures agreeing with those required for ditEesyZ~as.apheIzylene- 0.1217 gave 0.3507 CO, and 0,0616 H,O. 0,1166 C=7S.59 ; H=5*62. ,, 5.0 C.C. moist nitrogen at 14' and 768 mm. N=5*03. C,,H,,N,O, requires C = 78.68 ; H = 5.53 ; N = 4.S3 per cent. We tried to convert didesylparaphenylenediamine into the cor- responding benzodipyrrhole derivative by heating it with zinc chloride. It is possible that this transformation does take place, but the product was a mixture of two substances (needles melting at 318' and prisms melting at 335O-both yellow coloured) of almost1046 CHATTAWAY AND ORTON: A SERIES OF equal solubility ; so that, with the small quantity at our disposal, we were unable to separate them. The foregoing five papers form a continuation of a general in- vestigation of the reactions of ketonic compounds (compare Trans., 1897, 71, 123), and the expenses incidental to the work have for some years past been defrayed by various grants from the Government Grant Fund of the Royal Society. C!HEMIChL DEPARTMENT, UNIVEltSITY OF ABEILDEEN.