226 ilz. CHARLES GERHABDT’S RESEARCHES ON THE XXII.-Researches on the Anhydrous Organic Acids BY CHAS. GERHARDT. (Continuation from a Letter to Dr.WILLIAMS ON.) In continuing the researches of which I had the honour of COM-rnunicating the commencement to the Society I have found a valuable reagent not yet used in organic chemistry and extremely valuable for the preparation of various chlorides used in the formation of anhy- drous acids. This reagent is the oxychloride of phosphorus PO Cl, a liquid which effects the decomposition of a great number of salts as easily as it decomposes water and enabled me among other things to prepare Acetic chloride c w 0c1 ANHYDROUS ORGANIC ACIDS. a colourless liquid very mobile and boiling at 56' C.It fumes slightly in the air and is decomposed by water into acetic and hydro- chloric acids. With this new chloride I have obtained several new active compounds by double decomposition. I prepare acetic benzoate or benxoic acetate by the action of acetic chloride on dry benzoate of soda C H50,Na. The reaction is very brisk and is soon completed without the aid of external heat The syrup produced washed with water and carbonate of soda leaves an oil heavier than water neutral to test-paper and possessing an agreeable odour of Spanish wine. This oil is easily purified from water and other foreign matters by agitation with ether free from alcohol; and after the ether has been removed by a gentle heat the product shows by analysis the composition Boiling water renders it acid but the complete decomposition requires a long action; and the intervention of alkalies is needed as in the case of ethers.When subjected to distillation acetic benzoate separates at about 150' into anhydrous acetic acid (acetic acetate) and anhydrous benzoic acid (benzoic benzoate). There is evidently a double decomposition between two molecules This reaction perfectly explains the formation of anhydrous acetic acid as described in my last communication (from benzoic chloride and acetate of potassium). Acetic cuminate or cuminic acetate is obtained in the same manner as the above anhydride. Freshly prepared it is a fragrant oil which preserves its liquid form in a stoppered bottle; but a few moments contact with the air is sufficient to make it crystallise magnificent needles being formed until the mass assumes the appear- ance and consistency of frozen olive oil.Analysis shews that this change of state is accompanied by no change of composition of the body I have also succeeded in preparing in a state of purity benxoic cinnamate or cinnamic benzoate a heavy almost inodorous oil containing Q2 M. CHARLES GERHARDT'S RESEARCHES &c. 228 as well as the benxoic cuminate or cuminic benzoate a similar heavy oil containing Pinally also anhydrous cuminic acid or cuminic cuminate is obtained by the same process in the form of a heavy oil resembling a fatty oil an$ possessing a very faint smell. This oil also crys-tallises after a time; but the oil and the crystals present the same composition C, Hg2O3 -Cl Hll 0 1 am continuing these experiments with butyric valerianic and citrobenzoic acids and hope soon to be able to communicate my results to the Society.In concluding this notice I wish to call the attention of chemists to a remarkable analogy which exists between certain organic com-pounds belonging to the type water and certain others which I compare to the type hydrogen as represented by the following parallel which I submit to the consideration of experimenters. I. o Water :}Free hydrogen . . . 'Hl c H5 Hydride of Ethyl homo-c2H5 Alcohol. H} logous to marsh-gas . H } '2 '5}O Ether. '2 H5 c2H5}Ethyl . . . . . . c H '2 H H3 O )Aldehyde . . . 2 '10 Acetic acid. '2 H3 } Acetyl to be found . c2 o}0 Anhydrous C H3 0-acid acetic c2 H3 0 CH3 '2 H3 . ')Acetone . . . . '2C H3 H O} 0 Acetate of Methyl. This comparison enables me to foretel that acetyl and in general those oxygenised groups which act like hydrogen (oxygenisedradicals) will be obtained by the reaction of the corresponding chlorides on the metallic aldehydates; and in like manner the ketones by acting on the metallic aldehydates by the hydrochloric ethers. The experiments and considerations published on this last point by M. Chancel seem to me quite decisive.