Phosphorus pentachloride, action

Phosphorus pentachloride is prepared by the action of chlorine on phosphorus trichloride. To push the equilibrium over to the right, the temperature must be kept low and excess chlorine must be present. Hence the liquid phosphorus trichloride is run dropwise into a flask cooled in ice through which a steady stream of dry chlorine is passed the solid pentachloride deposits at the bottom of the flask. 

One of the general methods for the preparation of acid chlorides is the action of phosphorus pentachloride on the corresponding carboxylic acid ... 

Nitrophenyl isocyanate has been prepared by heating -nitrophenyl carbamyl chloride. The latter has been obtained by the action of phosgene on -nitroaniline in benzene-toluene solutions, and by the action of phosphorus pentachloride on methyl jii-nitrophenylcarbamate. The preparation given above is based upon recent publications of the authors. ... 

The method is essentially that discovered by Boeseken and Prins - and studied further by Prinsd Pentachloroethane can be used in place of tetrachlorethylene, as it is converted into the unsaturated compound in the presence of aluminum chloride. irwiyw.-Heptachloropropane has been obtained also by the action of phosphorus pentachloride on pentachloroacetone, and by treating dichloroacetyl chloride with aluminum chloride. ... 

Constitution. Pelletierine behaves as a secondary amine and the oxygen atom of the alkaloid is present in the form of an aldehyde group, since the base yields an oxime, convertible by the action of phosphorus pentachloride into a nitrile, b.p. 104-6°/13 mm., which is hydrolysed by caustic potash in alcohol to an acid, the ethyl ester of which is Loffler and Kaim s ethyl -2-piperidylpropionate. Pelletierine is not directly oxidisable to this acid. It also yields a liquid hydrazone, b.p. 130°/20 ram., which with sodium in alcohol at 136-70° reduces to dZ-eoniine. These reactions are explained by the following formulas, in which pelletierine is represented as -2-piperidylpropionaldehyde. 

Tropic Acid. The constitution of both tropic and atropic acids is known from syntheses by Ladenburg et al. from acetophenone. The ketone (I) by treatment with phosphorus pentachloride was converted into a-dichloroethylbenzene (II), and this, by the action of potassium cyanide in alcohol, into ethoxycyanoethylbenzene (III), which on hydrolysis yielded ethylatrolactic acid (TV). The latter was converted by strong... 

In an effort to prepare 1 2-dihydropapaverine, Buck dehydrated with phosphoryl chloride, and subjected the product (V) to catalytic reduction, followed by the action of phosphorus pentachloride in the cold. The final product was assumed to be 1 2-dihydropapaverine but Young and Robinson interpret this synthesis differently, and their formulae (V) and (VI) are given above, the final product being 3 4-dihydropapaverine (VII), which Buck thus prepared for the first time in a crystalline condition, m.p. 97-8° picrate, m.p. 151° perchlorate, m.p. 238° dec.). 

Dihydro-l-oxo-3,4-benz-j8-carboline (166) reacted with phosphorus oxychloride and one mole of phosphorus pentachloride at 110° to give l-chloro-3,4-benz-j8-carboline (264). When, however, more than one mole of phosphorus pentachloride was used 265 was obtained, presumably by chlorination of 264. This chlorinating action of phosphorus pentachloride is analogous to that observed when an... 

It yields a chloride, thujyl chloride, Cj H jCl, by the action of phosphorus pentachloride, which on treatment with aniline yields up HCl, with the formation of the terpene thujene. 

By the action of phosphorus pentachloride, cedrenol yields cedrenyl chloride, CisHggCl, which, when reduced by sodium and alcohol yields cedrene. 

By the action of phosphorus pentachloride it yields betulyl chloride, a partial molecular rearrangement having apparently taken place, since, on hydrolysis, it yields a tricyclic betulol which is of particular interest in that it is the first tricyclic sesquiterpene alcohol of a crystalline character to be discovered. Its characters are as follows —... 

Protocatechualdehyde has been made by a variety of methods, but is usually prepared from catechol by the Reimer-Tiemann method 1 by demethylation of vanillin,2 or veratric aldehyde 3 or from piperonal by the action of phosphorus pentachloride followed by hydrolysis.4... 

Phosphorus Pentachloride (Phosphoric chloride, Phosphorus perchloride). PC15, mw 208.27 white to pale yel, fuming, deliq, cryst mass pungent, unpleasant odor mp (under press) 148° ordinarily sublimes without melting at 160—165°. Sol with decompn and liberation of much heat in w or ale sol in C disulfide or tetrachloride. Can be prepd by the action of chlorine on P or P trichloride (Refs 9 10)... 

Chloroanthracene has been prepared by the action of chlorine,2 tert-butyl hypochlorite, l,3-dichloro-5,5-dimethylhy-dantoin, or phosphorus pentachloride 5 on anthracene. 

Ethyl fumarate has been prepared from fumaric acid and ethyl alcohol, with or without sulfuric acid as catalyst,4 from silver fumarate and ethyl iodide,5 from silver maleate and ethyl iodide plus a trace of iodine,6 from ethyl maleate by the action of iodine,6 from ethyl maleate and phosphorus pentachloride,7 and by passing hydrogen chloride into a boiling absolute alcohol solution of malic acid.8... 

Triphenylchloromethane has been made by the action of phosphorus pentachloride,1 hydrogen chloride,2 or acetyl chloride3 upon triphenylcarbinol. It has also been made by the reaction between carbon tetrachloride and benzene in the presence of alumi-... 

Fluoroacetyl chloride, CH2FCOCl, was prepared by the action of phosphorus pentachloride on the free fluoroacetic acid (p. 121).1 It is extremely useful as fluoroacetylating agent in synthetic work. Because of its importance we have recently reinvestigated other methods of preparation.2 These may be summarized as follows (1) direct from fluoroacetamide (p. 125) by the action of phosphorus oxychloride and water (2) the action of phosphorus oxychloride on either sodium fluoroacetate (p. 121) or on barium fluoroacetate (p. 121). Good yields are obtained in both (1) and (2), and in each case the starting materials are more easily available than fluoroacetic acid itself. 

This interesting derivative of ketene is also obtained from benzilic acid by the old process of Staudinger the add is converted, by the action of phosphorus pentachloride, into diphenylchloracetyl chloride from which the two chlorine atoms are removed by means of zinc. (Formulate this equation.) What is carbon suboxide For information about the ketenes see H. Staudinger, Die Ketene, Stuttgart, 1912. 

The oxychloride also is obtained by the action of boric acid or oxahc acid with phosphorus pentachloride ... 

Nitrobenzoyl chloride has been prepared only by the action of phosphorus pentachloride on />-nitrobenzoic acid.1... 

Racemic 2-ethylhexanonitrile has been obtained only by the action of phosphorus pentachloride on 2-ethylhexanaldoxime 4 the levorotatory form has been prepared from the active amide by the method described.6 Other amides have been converted to nitriles by dehydration with thionyl chloride.6-6... 

Other methods of preparing flavone include the action of ethanolic alkali on 2 -acetoxy-a,/3-dibromochalcone 7 Claisen condensation of ethyl o-ethoxybenzoate and acetophenone, and cyclization of the resulting 1,3-diketone with hydriodic acid 8 and treatment of 3-bromoflavanone with potassium hydroxide in ethanol.9 Flavone has also been prepared from ethyl phenyl-propiolate by condensation with sodium phenoxide and subsequent cyclization with phosphorus pentachloride in benzene 10 by fusing o-hydroxyacetophenone with benzoic anhydride and sodium benzoate 11 by the dehydrogenation of 2 -hydroxychal-cone with selenium dioxide 12 and by the action of alkali on flavylium chloride.13... 

The action of phosphorus halides on pyrrolinones and related compounds offers an alternative route to chloropyrroles. Yields of around 60% of 2,5-dichloropyrroles were obtained in this way from N-substituted succinimides (82ZC126). Vilsmeier reaction of N-alkylsuccinimidals formed chlorinated pyrrole aldehydes in modest yields (90CJC791), and there are other examples [66YZ158 81H(15)547]. A useful synthesis of chloropyrrole-2-carboxylates employed the action of phosphorus pentachloride on pyrrolidin-2-one-5-carboxylates (40) (87CB45) (Scheme 15), and in a Pummerer-type reaction pyrrol-3-yl sulfoxides were transformed by thionyl chloride into chloropyrroles. Yields were increased to >80% by the use of oxalyl chloride (88JOC2634) (Scheme 15). 

Benzoic anhydride has been prepared in rather a poor yield by the action of benzoyl chloride on sodium benzoate, barium oxide at 150°, benzoic acid at 160-200°, sodium nitrite, lead nitrate, or anhydrous oxalic acid also by treating sodium benzoate with phosphorus pentachloride or sulfm chloride. More important methods consist in treating benzotrichloride with sulfuric acid,i° and in the action of sodium carbonate upon benzoyl chloride in presence of pyridine. 

Methanesulfonyl chloride has been prepared by the chlorination of methyl thiocyanate, S-methylthiourethan, sodium methyl thiosulfate or S-methylisothiuronium sulfate from sodium methanesulfonate by the action of phosphorus penta-chloride, phosphorus oxychloride, or benzotrichloride from methanesulfonic acid by the action of phosphorus pentachloride or by the reaction of methylmagnesium iodide with sulfuryl chloride. ... 

Ilosvay) by the action of hydrogen chloride on iodic acid (G. S. Serullas) of phosphorus pentachloride on iodine pentoxide (0. Brenkn) of iodine on sulphuryl chloride in excess (0. Ruff) 3S02Cl2+l2=2ICl3+3S02 and by heating iodine monochloride. 

Various other processes can be made to yield sulphur monoehloride. The distillation of sulphur with stannous chloride or mercuric, chloride yields sulphur monochloride and, indeed, may be regarded as a modification of the method first given. The action of phosphorus pentacliloridc on sulphur or on metallic sulphides and the action of chlorine on metallic sulphides form closely analogous processes, especially in view of the formation of chlorine as a dissociation product from phosphorus penta-chloride. With phosphorus pentachloride tire phosphorus is found finally as sulphochloride. Of other methods there may be mentioned the interaction of sulphur or of phosphorus sulphide with thionyl chloride,6 and the action of dry chlorine on a hot or boiling solution of... 

Sulphuryl Chloride, S02C12.—As would be expected, it is possible to obtain an acid chloride, S02C12, corresponding with sulphuric acid, SO2(OH)2, but the chloride cannot be prepared by the action of phosphorus pentachloride on sulphuric acid or sulphur trioxide, these reagents yielding pyrosulphuryl chloride.7... 

Pyrosulphuryl Chloride, S205C12.—Rose first prepared this substance in 1838 by the interaction of sulphur trioxide and sulphur monochloride.4 It is formed by the action of many chlorides on sulphur trioxide sulphur monochloride,4 thionyl chloride,5 silicon tetrachloride,6 phosphorus pentachloride,7 phosphorus oxychloride,8 sodium chloride 9 and carbon tetrachloride 10 all yield the desired product when treated with sulphur trioxide at a suitable temperature. With sodium chloride a mixture of pyrosulphufyl chloride and sodium pyrosulphate is obtained, whilst with the exception of carbon tetrachloride and phosphorus pentachloride, which are converted into oxychlorides, all the remaining chlorides are changed into oxides ... 

Whilst the formation of thionyl chloride by the action of phosphorus pentachloride on an alkali sulphite favours a symmetrical structure for the latter, the interaction of an alkali sulphite with ethyl iodide, as mentioned already, is directly opposed to this evidence, as also is the production of sodium sulphite on reducing sodium dithionate with sodium.5 The remaining inorganic evidence is little more satisfactory. 

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