9 1x1.-Action qf Pentachloride of Plzosphorus on Tartaric Acid. BY W. I€. PERKIN, F.C.S. AND B. F. DUPPA,ESQ. IN a paper on malic acid published last April in the Philosophical Magazine we mentioned that Tve were engaged with the study of the influence of pentachloriclc of phoqphorus on Tartaric acid; our time however having been much occupied by other subjects we have as yet been unable to investigate the matter thoroughly but having obtained some peculiar results we take this opportunity of laying them before the Society. On gently heating a mixture of pentachloride of phosphorus arid tartaric acid hydrochloric acid is evolved in abundance and a perfectly liquid mixture is formed consisting of oxychloride of phosphorus and an oil. To obtain the latter in quantity we have found it best to operate in the following manner.One part of pulverized tartaric acid and file or six of penta- chloride of phosphorus are mixed and introrluccd into a retort and gradually heated until perfcctly liquid. The temperature is then elevated and the liquid alloived to distil until it reaches 120";it is maintained at this point and dry air passed through the remaining liquid for five or ten minutes so as to separate as much of the remaining oxychloride of phosphorus as possible. This product which is the chloride of a diatomic acid radical sinks as an oil mlien thromn in water and gradually dissolves. It also dissolves in alcohol forming an ethereal body. If projected into strong aqueous ammonia a violent action ensues chloride of ammonia and a new crystalline compound very soluble in stlcohol and vater being produccd.V7ith phcnylamine this body reacts most energetically. It decomposes partially on being distilled. As mentioned above this substance gradually dissolves i-rtwater. If a considerable quantity is mixed with water it becomes warm and on cooling deposits a white slightly crystalline acid. If exposed to the moist atmosphere for a day or two it becomes a white solid mass. This acid after being well pressed between bibulous paper and recrystallized from water presents itself as tt white almost amor- phous mags but when viewed under the microscope appears as small transparent needles. It is very soluble in water and alcohol has a very acid taste melm when heated and so’lidifizs into r?.crystalline mass on cooling. It is bibnsic. Acid potassiui~4-sdt. This is Ixst obtained by taking a solution of the acid aid di~idirig it irito tvt-o cqual portions neutralizing me nitli carbonate of ptas~i~ilil am1 then adding the otlicr to it. If not too dilute the new salt immediately makes its appearance as a crystalline precipitate which after washing with cold water and recrystallizing once or twice is obtained quite pure. Tt crystallizes in plates. It is more solrtble than the acid tar-tarste of potassium. It contains chlorine. The following carbon hydrogen chlorinc and potassium dcterrninations have been made 1. *3290 of substance gave *3033 of carbonic acid and -0329 of water.11. 2064 of substance ga\re *15G7 of chloride of silver. 111 *69525of substance gave ~271of chloride of potassium. Percentage composition :-Carbon 25.14 Hydrogen . . 1.11 Chlorine . . 18.82 Potassium . 2045 which agrees with the formufa K€I,C&(HCl) 0 as may be seen from the following table :- Theory. EX~. Carbon 8 equiv. . . 48 25.4 25-14 Hydrogen 2 , . . z 1 -05 1.11 Chlorine 1 , . 35.5 18.81 18-82 Potassium 1 , . . 39.2 20*77’ 20*45 Oxygen 8 , . . 6-kO 33.97 188-7 100.00 The neutrnl potassium-salt is crystalline and much more soluble than the former. PENTACHLORIDE OF PIrosrrIoms ox TARTARIC ACID. 11 Siluer-saZt.-On adding nitrate of silver to a solution of either of the above salts a white prccipitate is irnmediatcly formed this when washed with cold water and dried in vacuo over sulphurie acid is fit for analysis.It is very slightly soluble in water. Wlicn viewed under a powerful lens it presents a slightly crystalline appearance. On being heated on platinum foil it decrepitxtes leaving a residue of metallic silver and chloride of silver. The subjoined determinations mere made :-I. 02655 of substance gave -210 of chloride of silver. IT. *%I325 of substance gave -1737'5 of metallic silver and 1I 7 of cliloride of silver. Percetltage composition :-I 11. Silver . . 59.5 . . 5925 Chlorine. . . 9.50 These numbers agree with the formula Ag,,C,(HCl)O as may be seen from the following table :--Theory. Exp. Carbon 8 equiv.. . 48 13.16 ___I Hydrogen 1 , . .1 -27 Chlorine 1 , . . 35.5 9.74 9.50 Silver 2 , . . 216.0 59-23 5937 Oxygen 8 , . . 64.0 17.60 -364.5 100.00 Lead-satt. This salt is obtained by adding acetate of lead to a solution of the potassium salt. It is a crystalline substance dif- ficultly soluble in water. From the foregoing it evidently appears that the new acid has the composition C,(H,Cl)O, and the chloride from which it is derived the formula C,(HCl) O,,Cl,. This acid in composition represents maleic or fumaric acid in which one equivalent of hydrogen is replaced by chlorine; but as it is a very soluble sub-stance it would appear that if derived from either of the above it would be from maleic acid therefore we give it the provisional GLOXAM ON THE DETECTION OF name of chloromaleic acid.We hope shortly to be able to replace the chlorine in this acid by hydrogen and then to ascertain whether it miglrt be vieivecl as a dcriwtive of maleic acid or not because this is important as it may show 11s the relation which tartaric acid bears to malic. The action of pentachlwide of phosphorus may be explained thus :-C,H60, + PC1 = C8H40j0 + PCl,O + 2I-IC1. Tartaric acid. Anhyd. tart. acid. New chloride. This appears to show that tartaric acid represents four molecules of water and that part of the hydrogen and oxygen exist in the same peculiar condition as in glycolic and lactic acid. The formula of tartaric acid appears to be c8Er2041 % O8 We have obtained some wry interesting substances by digesting the bromacetic ethers with sulphocyanides acetates succinates &c. the study of which we are now engaged with.