1156 GARDNER AND COCKBURN: ACTION OF CX.-Action of Phosphorus Pentachloq*ide oya Fen- chone. By JOHN ADDYMAN GARDNER, M.A., and GEoRaE BERTRAM COCKBURN, B.A. FENCHONE and fenchene are usually considered to be anaiogous to camphor and camphene in their behaviour, and on this supposition chemists have based various formulae for fenchone, which dependPHOSPHORUS PENTACHLORIDE ox PENCHONE. 1157 somewhat on their views as to the constitution of camphor. The ground for this analogy is a comparison of the properties of fencholenic and campholenic acids, fenchylamine and bornylamine, &c. (Wallacb, Acnmlelz, 1892, 269, 356), and the change of fenchone and camphor into isomeric cymenes (ibid., 1893,275,157). It seems to us, however, that before the exact relationship between fenchone and camphor can be expressed symbolically, a much more elaborate comparison of the behaviour of these substances must be made.I n order to contribute to this, we have investigated the action of phosphorus pentachloride on fenchone. By the action of phosphorus pentachloride on camphor in the cold, Marsh and Gardner (Trans., 1897, 71, 288), obtained two isomeric forms of chlorocamphene hydrochloride, C,,H,,CI,, both of which, on saponification, yielded the same chlorocamphene. Fenchone under similar conditions is acted on very much more slowly, and the pro- ducts of the action are different, for on pouring into water to get rid of the excess of phosphorus pentachloride and oxychloride, we obtained a crystalline compound of the formula CloHl,CIPO(OH),, which we name chlorofenchenephosphonic acid, an oil consisting of unchanged fenchone, and a substance containing chlorine, probably chlorofenchene, CloH,,C1.The reaction probably takes place according to the follow- ing equations- C10H160 + Pel, = CIoH16Cl, + Poc1, = CloHl5C1 + Hcl+ Pocl,. CloH15Cl + PC1, = C, ,Hl,CIPCl, + HCl. CloH14C1PCI, + 3H,O = C1,H1,C1PO(OH), + 4HC1. Fifty grams of fenchone, b. p. 190-191”, m. p. 6-’i’’,and specific rotatory power [a],, = 61O 58’, were mixed with 200 grams of phosphorus penta- chloride in a flask closed with a calcium chloride tube, and allowed to stand at the ordinary temperature for six weeks. A very slow reaction took place with a very gradua,l evolution of hydrogen chloride. After the evolution of the gas had, to all appearance, ceased, the pro- duct was poured into a large quantity of ice and left overnight. The oil obtained in this way was taken up with ether, dried, and allowed to stand, when crystals of chlorofenchenephosphonic acid slowly separated.Afterthe separation of crystals had ceased, the oil was shakenupwithvery dilute sodium carbonate solution, when a further quantity of the substance was obtained in the form of sodium salt. A small quan- tity more was also obtained from the water into which the phosphorus compound had been poured, on extracting it with ether. The total amount of acid obtained from 50 grams of fenchone was about 7 grams, corresponding with a 14 per cent. yield. For this purpose, it was exactly neutralieed with a dilute solution of caustic The acid was purified by conversion into the sodium salt.115s ACTION OF PHOSPHORUS PENTACHLORIDE ON FENCHONE.soda, evaporated to dryness, the residue dissolved in absolute alcohol, and ether added until the solution became somewhat turbid ; on stand- ing, the salt crystallised ont in white, needle-shaped crystals. It was then dissolved in a small quantity of water, acidified with hydrochloric acid, extracted with ether, and the residue left on evaporating the ether was crystallised several times from water, in which it was only sparingly soluble, and finally from acetone. It was thus obtained in white, crystalline plates melting a t 196'. It was very soluble in ether, alcohol, chloroform, and benzene. On analysis, the acid gave the following figures :- I. 0.2002 gave 0.3502 CO, and 0.1 199 H,O.11. 0.2528 ,, 0,4429 CO, and 0.1459 H,O. 111. 0.3606 ,, 0,2065 AgCl. IV. 0,2174 ,, 0.0951 Mg,P,O,. I. I I. Found. Calc. for C,,H,,C!lPO(OH),. Carbon ............ 47.70 47.78 47-92 Hydrogen , . . , . . 6.65 6.41 6-38 Chlorine ......... 14.17 - 14.13 Phosphorus ...... 12.21 - 12.37 The specific rotatory power [a], = 7" 56' in alcoholic solution. The saturating power of the acid was determined by titrating it with caustic soda solution, using phenolphthalein as indicator; with an aqueous solution of the alkali, the results were in all cases about 2 per cent. too low, but by working in alcoholic solution very satisfactory results were obtained 0.5458 gram of acid required 9.2 C.C. of alkali (I C.C. = 0.01 1 gram sodium). Calc. amount of sodium req1iir.d by 100 gram of Cl,Hl,CIPO(OH),.Found. 18.36 18-54 The insoluble lead salt, prepared from lead nitrate and the sodium 0.4365 gave 0.2876 PbSO,. C,oH,,CIPO,Pb requires P b = 45.3 per cent. The barium and copper salts are also insoluble, and may be prepared from the sodium salt by precipitation ; these salts are soluble in mineral acids, but are reprecipitated unchanged on adding an alkali. The copper salt bears a close resemblance in colour and appearance to copper phosphate. The silver salt can also be obtained as a dirty white pre- cipitate by adding concentrated silver nitrate solution to a strong solu- tion of the sodium salt, It is slightly soluble in hot water and behaves with acids like the copper salt. salt, gave the following figures on analysis :- Pb = 44.94.SPRANKLING : KETOLACTONIC ACID AND ITS HOMOLOGUES.1159 The oil left after the extraction of the phosphonic acid consists of a mixture of fenchone with a substance containing chlorine; on dig- tilling it under a pressure of 20 mm., it could be separated, without decomposition, into two fractions,’the lower boiling a t 90-95’, and the higher a t 120-125’. The lower fraction, which consisted of fenchone, distilled at 188-1 90’ under the ordinary pressure ; from its amount it was evident that less than 50 per cent. of the original fenchone had re- acted with the pentachloride. The fraction of higher boiling point contained chlorine, the amount of which was determined by Carius’ method. 0,2518 gave 0.1699 AgC1. It probably consists mainly of chlorofenchene, and on treatment with concentzated sulphuric acid gave off hydrogen chloride. On treat- ing the black product with water and distilling in steam, an oil came over which smelt of geraniums, and reacted with pentachloride of phos- phorus, although not vigorously. The quantity of chlorofenchene at our disposal was, however, too small for purification, and we are a t present engaged in preparing it in quantity, in order t o purify it and compare its reactions with those of the chlorocamphene obtained in a similar way. C1= 16.7 CloHl,Cl requires C1= 20.8 per cent. CHEMICAL LABORATOILY, ST. GEORGE’S HOSPITAL.