DIARYLOXYISOPROPYLPHOSPHOROUS ACIDS. 1221 CXX1X.-Action of the Chlorides of Phosphorus on Aromatic Ethers of Glycei-ol. Dimryloxyisopropyl- phosphorous Acids. By D. R. BOYD. SYMMETRICAL glycerol diphenyl ether, OPh*CH,*CH(OH)*CH,*OPb, was originally prepared by Rijssing (Ber., 1886, 19, 63) from u-di- chlorohydrin. Lindeman (Bey., 1891, 24, 2147) has since obtained both the diphenyl and di-ptolyl ethers more conveniently by using epichloroh ydrin. These compounds appear to be the only representatives of the diary1 ethers of glycerol which have been described, and their properties have VOL. LXXIX. 4 P1222 BOYD: ACTION OF THE CIILORIDES OF PHOSPHORUS ON not been very completely investigated. I recently had occasion to study the action of the chlorides of phosphorus upon the diphenyl ether, and the results obtained in this and some similar cases are recorded in the present paper.When glycerol diphenyl ether is treated with phosphorus penta- chloride, the corresponding diphenoxyisopropyl chloride is formed. OPh*CH,*GH(OH)*CH,*OPh 4 OPh-CH,*CHCl*CH,*OPh. If, on the other hand, phosphorus trichloride is used, and the pro- duct of the reaction treated with water, a large yield of diphenoxy- isopropylphosphorous acid is obtained. CH(CH,*OPh),*OH + PCI, = CH(CH,*OPh),*O*PCI, + HCl. CH(CH2*OPh),*O*PCI, + 2H20 = CH(CH,*OPh),*O*P(OH), + 2HC1. Similar results follow if glycerol phenyl p-tolyl ether or the d i p tolyl ether is substituted for the diphenyl compound. The behaviour of alcohols towards phosphorus trichloride has been investigated by various chemists (Wurtz, Menschutkin, Kowalewsky), who have shown that either an ester of phosphorous acid, for example, C,H,*O*P(OH),, or the corresponding chloride, C2H,*O*PCl,, is formed according to the proportion of alcohol used.More recently, Jaroschenko (Chem. Cent?.., 1897, ii, 334) has suggested the employment of this reaction as a means of distinguishing between primary, secondary, and tertiary alcohols. According to this author, primary alcohols react with phosphorus trichloride to give phosphorus compounds of the type R*CH,*O*PCI,, the yield in the case of isobutyl alcohol being 78 per cent. of the theoretical amount (compare also Kowalewsky, Chent. Centr., 1897, ii, 333). Secondary alcohols, on the other hand, yield unsaturated hydrocarbons according to the equation : 3CH,*CH(OH)*CH, + PCI, = 3CH3*CH:CH, + 3HCl + P(OH)3, the yield of propylene obtained from isopropyl alcohol being 80 per cent.of that required by theory. Milobendski (Chem. Centr., 1899, i, 249), however, has been unable to verify this observation in the case of isopropyl alcohol. He finds, on the contrary, that when phosphorus trichloride acts on this alcohol, only a very small quantity of propylene is formed, and that the main reaction proceeds according to the equation : 3C,H,O + PCl, = P(O*C,HT),*OH + C,H,C1 + 2HC1. I n view of these conflicting statements, a study of the action of phosphorus trichloride upon the glycerol diary1 ethers acquires addi- tional interest. From the observations recorded in the present paper, it is evident that some secondary alcohols at least behave precisely in the fashion which has been recognised by Jaroschenko as characteristieAROMATIC ETHERS OF GLYCEROL.1223 of primary alcohols. The use of phosphorus trichloride as a reagent for the recognition of the primary or secondary character of an alcohol must therefore be regarded as of very doubtful value, The diaryloxyisopropylphosphorous acids here described are sub- stances with a marked tendency to crystallise, and show a some- what high degree of stability when compared with other derivatives of phosphorous acid of the same type already known. They undergo no change when left exposed to moist air, and can even be crystallised from boiling water. Solutions of their ammonium salts may be boiled for a long period without any decomposition taking place.The com- pounds, however, are quickly hydrolysed by heating with caustic potash. EX P E R IY EN T A L. Actiort of Phosphorus Pentachloride on s-Glycerol Biphenyl Ether. Formation of Diphenoxyisopropyl Chloride, C,H,*O* CH,*CHC1*CH2*O*C,H,. The glycerol diphenyl ether used in this and the following experi- ment was prepared by Lindeman’s method. It melted a t 80--81°.* Twenty-four grams of the ether (1 mol.) were mixed with 22 grams of phosphorus pentachloride (1 mol.). I n a few minutes, a vigorous reaction took place, resulting in the formation of a yellow liquid. This was poured into water and heated with dilute caustic soda solution until the smell of phosphorus oxychloride had disappeared. The alkaline liquid was then extracted with ether, and the ethereal solu- tion dried over potassium carbonate.On evaporation of the ether, an oil was obtained which was distilled under reduced pressure. The distillate, on standing, solidified. Jt was dissolved in light petroleum, from which, on cooling, it separated in large, transparent, oblique prisms melting at 3i0. The yield was 7.5 grams, or about 30 per cent. of the theoretical amount, On analysis : 0.1534 gave 0.3862 CO, and 0.0848 H20. C = 68.66 ; H = 6.19. 002092 ,, 0.1156 AgC1. C1= 13-67. C,,H,,O,CL requires C = 68.55; H = 5.77 ; 01 = 13.50 per cent. * In this connection, it may be mentioned that an unsuccessful attempt was made to prepare as-glycerol diphenyl ether from P-dibromohydrin. When this substance was treated with a mixture of sodium phenate and melted phenol, a satisfactory yield of a diphenyl ether was obtained, but this proved, on investigation, to be the same compound that results from a-dichlorohydrin or epichlorohydrin, namely, the symmetrical ether.This is no doubt to be explained by supposing that epibromo- hydrin is formed as 311 intermediate product by the action of the sodium phennte on the 8-dibromohydrin. 4 P Z1224 BOYD: ACTION OF THE CHLORIDES OF PHOSPHORUS ON The substance dissolves very easily i n ether, alcohol, and other organic solvents, and in small quantity can be distilled without decom- position under the ordinary pressure. Action, of Phosphorus 17ricl&~ids m s-Glycerol Diphenyl Ether. E'ormation of Diphenoxy isoprop ylphosphorous Acid.CH( CH2*O*C6H,),*O*P(OH),. I n each experiment, 13 grams (3 mols.) of the diphenyl ether and 9 grams of phosphorus trichloride (4 mols.) were used. The mixture was heated in the water-bath for about half-an-hour until no more hydrogen chloride was evolved, The resulting colourless liquid, con- sisting of the chloride of diphenoxyisopropylphosphorous acid, together with tbe excess of phosphorus trichloride, was cooled and then poured into a litre of ice-cold water, A somewhat vigorous reaction took place, with liberation of hydro- chloric acid. After stirring for a short time, a white, viscous mass wi s obtained, which, on standing, became solid. I n the first experiments, this product was extracted repeatedly with boiling light petroleum, in which the unchanged glycerol diphenyl ether dissolves, whilst the phosphorous acid is practically insoluble.It was afterwards found that a much more convenient method, and one giving a pure product, consists in treating the above-mentioned viscous mass a t once with a considerable volume of dilute ammonia solution. On standing some hours, the whole of the diphenoxyisopropylphosphorous acid dis- solves, leaving behind any unchanged glycerol ether. I n this operation, it is necessary t o use a rather large quantity of water, as otherwise the ammonium chloride which is formed, if any phosphorus tri- chloride should have escaped decomposition in the previous treatment with water, causes precipitation of ammonium diphenoxyisopropyl- phosphite. On acidifying the ammoniacal solution with hydrochloric acid, an oily precipitate of diphenoxyisopropylphosphorous acid was obtained, which soon changed to a crystalline mass.This was filtered off, and washed well with water containing some hydrochloric acid. The washed pro- duct was dried at 100' and crystallised from ethyl acetate, from which it separated in beautiful, prismatic needles, or radiating groups of these, melting at 119-120'. The yield was 9 grams, or about 55 per cent. of the theoretical amount. On analysis : 0.1839 gave 0.3923 CO, and 0,0928 H,O. C = 58.18 ; H = 5.66. 0.6867 ,, 0.2535 Mg,P,OF. P = 10.28. C,,H170,P requires C = 58.40 ; H = 5.57 ; P = 10.06 per cent. Diphenoxyisopropylphosphorous acid is slightly soluble in coldAROMATIC ETHERS OF GLYCEROL. 1225 water, giving a liquid mitb a faint acid reaction ; from this solution, it is reprecipitated on addition of a little hydrochloric acid." It is moderately soluble in boiling water, and, on cooling the solution slowly, separates in we31-developed, prismatic needles similar t o those obtained from ethyl acetate.It is very easily soluble in dilute aqueous am- monia, and if t o a concentrated solution some ammonium chloride is added, the ammonium salt of the diphenoxyisopropylphosphorous acid is immediately precipitated in the form of an oil. This oil dis- solves at once on addition of more water, and no hydrolysis occurs, even on prolonged boiling OF the solution. The acid is also readily soluble in cold caustic soda solution, but on boiling the solution quickly becomes turbid from separation of the glycerol diphenyl ether.The liquid now contains phosphorous acid, and after acidification and subsequent filtration is found to reduce mercuric chloride solution. The substance dissolves very easily in alcohol, and somewhat less so in benzene, chloroform, acetone, or hot ethyl acetate, It is insoluble in ether, if free from alcohol, or in light petroleum. Glycerol PhenyZ p-ToZyZ Ether, C,H,* O*CH,*CH(OH)*CH,*O* C,H,*CH,. This substance was obtained by an adaptation of Lindeman's method for the preparation of the symmetrical ethers. A solution of p-cresol and sodium ethoxide in alcohol was treated with the theoretical amount of glycidol phenyl ether, and the mixture boiled for some hours in a reflux apparatus. The product was then cooled, poured into water, and the resulting solid precipitate washed with water, dried, and crystallised from alcohol.It formed white leaflets, which after several crystallisation8 melted at 73.5-76'. Repeated crystallisation did not alter the melting point. The sample analysed was obtained by hydrolysis of its phosphorous acid and sub- sequent crys tallisat ion. 0,2071 gave 0.5636 CO, and 0.1323 H,O, I n properties, the substance closely resembles the diphenyl and diptolyl ethers already described. It can be distilled under reduced pressure without decomposition, and may be crystallised conveniently either from alcohol or light petroleum. C= 74.22 ; H = 7.16. C,,HI,O, requires C = 74.37 ; H = 7.04 per cent. ie Autenrieth (Ber,, 1897, 30, 2371) draws attention to the same phenomenon in the case of acids of the type of diphenylphosphoric acid, and Wurtz (AnnaZen, 1846, 58, 75) records a similar behavionr on the part of amylphosphorous acid.1226 DIARYLOXYISOPROPYLPHOSPlXOROUS ACIDS Phenoxy - ptolytoxyisopropy I Chloride, C,X,*O* CH,- CHCl*CH2*O*C,H4*CH3.Molecular proportions of glycerol phenyl ptolyl ether and phos- phorus pentachloride were mixed and the product of the reaction treated exactly as in the case of the preparation of diphenoxyiso- propyl chloride. The substance crystallised from light petroleum in clusters of transparent plates of well-defined form melting a t 609 On analysis : 0-1624 gave 0*4130 CO, and 04895 H20. 0'2075 ,, 0.1055 AgCI. Cl=12*57. In solubility, volatility, &c., the substance closely resembles tho C=69*36 ; H=6.18. C,6H,p02C1 requires C = 69.41 ; H = 6-27 ; C1= 12.82 per cent.corresponding diphenoxy-compound. ~he~oxy-p-toEy~oxyisop~opyEp~~o~pho~ous Acid, C€T,*C,H4*O*CH,*CH( CH,*O* C,H,)*O P( OH),. Twenty grams of glycerol phenyl p-tolyl ether were heated with 16 grams of phosphorus trichloride and the product treated as in the case of the diphenyl compound, The substance crystallised from ethyl acetate in radiating clusters of needles very similar to those formed by the diphenoxy-derivative, and melted a t 106-107°. The yield was 16 grams, or about 65 per cent. of the theoretical quantity. On analysis : 0.1991 gave 0.4339 CO, and 0.1087 H20. 0.5528 ,, 0.1945 Mg,P207. P = 9-79. I n aolubility and general properties, the substance is very similar to the corresponding diphenoxy-compound. Its ammonium salt, which was obtained in the form of silky crystals, is very soluble in water and is precipitated from a concentrated solution on the addition of ammonium chloride.Di-ptolytoxyisopropyl Chloride, CH,*C,H,*O*CH,* CHC1* CH,*O* C, 8,*CH3. The glycerol di-p-tolyl ether used in the two following experiments was prepared from epichlorohydrin and p-cresol (Lindeman, loc. cit.). It melted at 88O. The ditolyl ether and phosphorus pentachloride were mixed in molecular proportion, the containing vessel being immersed in cold water in order to moderate the vigour of the reaction. The resulting liquid was treated with hot caustic soda solution and then extracted with ether as in the previous cases. On evaporation of the C = 59.44 ; H= 6.12. C,,H,,O,P requires C = 59.59 ; H = 5-96 ; P = 9-60 per cent.AUTOFERMENTATIOX AND LIQUEFACTION OF PRESSED YEAST. 1227 ether, the residue solidified. Distillation in a vacuum mas therefore omitted and the substance crystallised at once from light petroleum. It separated in small but well-developed, transparent rhombohedra melting at 70'. 0.1665 gave 0.0514 AgC1. The properties of this substance are exceedingly eimilar to those of C1 = 12.09. C17H190,C1 requires C1= 12.1 9 per cent. the diaryloxyisopropyl chlorides already described. Di-p-toylyylox~isop~~o~~yl~~os~ho~o~s Acid, CH(CH,* 0. C,H,aCH,),*O*P(OH)2. This substance wasprepared in a manner quite analogous to that employed in the two previous corresponding cases. It crystallised from ethyl acetate in a very similar fashion, the crystals melting at 111-112°. On analysis : 0.4712 gave 0.1597 Mg,P,07, I n general properties, this substance ,resembles its two lower homo- logues very closely. It is precipitated from its aqueous solution on addition of hydrochloric acid, and its ammonium salt is precipitated on addition of ammonium chloride. The study of these and some allied compounds is being continued. P= 9.43. CI7H,,O,P requires P = 9.23 per cent. CHEMICAL DEPARTMENT, HARTLEY COLLICGE, SOUTHAMPTON,