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MALONE

Online Encyclopedia
Originally appearing in Volume V17, Page 495 of the 1911 Encyclopedia Britannica.
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MALONE, a village and the county-seat of Franklin county, in the township of Malone, in the N.E. part of New York, U.S.A., about 6o m. E.N.E. of Ogdensburg. Pop. (189o), 4986; (1900), 5935 (910 foreign-born); (1905. state census), 6478; (191o),, 6467. It is served by the New York Central & Hudson River and the Rutland (N.Y. Central Lines) railways. The village has a Memorial Park, Arsenal Green, on the site of an arsenal and parade-ground sold by the state in 185o, a state armoury, CC12:CH•000C2H5 + Ag2O + H20= 2AgC1 + HOOC•CH2•COOC2H5. It crystallizes in monoclinic tables, and is readily soluble in water, alcohol and ether. The acid melts at 132° C., and at a higher temperature it rapidly decomposes into acetic acid and carbon dioxide. When heated with bromine and water to rod° C. it forms tribromacetic acid, some bromoform being produced at the same time. Malonic acid, as well as its esters, is characterized by the large number of condensation products it can form. In the presence of a dehydrating agent (such as acetic anhydride), it combines with aldehydes to form compounds of the type R • CH: C(COOH)2, or their decomposition products (formed by loss of CO2) R • CH : CH • COOH. Many salts of the acid are known and, with the exception of those of the alkali metals, they are difficultly soluble in water. Many esters of malonic acid have been prepared, the most important being the diethyl ester (malonic ester), CH2(000C2H5)2, which is obtained by dissolving monochloracetic acid in water, neutralizing the solution with potassium carbonate, and then adding potassium cyanide and warming the mixture until the reaction begins. When the reaction has finished, the whole is evaporated and heated to about 130`-140° C. and then allowed to cool. The mass is then covered with two-thirds of its weight of alcohol, and saturated with hydrochloric acid gas. The whole is then poured into ice-cold water, extracted by ether and the ethereal solution distilled (L. Claisen, Ann., 1883, 218, p. 131). It is a colourless liquid boiling at 197°•7 -198°•2 C. (W. H. Perkin). It is a most important synthetic reagent; with sodium or sodium ethylate it forms sodio-malonic ester, which reacts readily with alkyl halides, forming alkyl malonic esters, which are again capable of forming-sodium derivatives, that by further treatment with alkyl halides yield the di-alkyl malonic esters. These esters are readily hydrolysed and yield the mono-and di-alkyl malonic acids which, on heating, are readily decomposed, with evolution of carbon dioxide and the formation of mono- and di-alkyl acetic acids. The scheme of reactions is shown thus: R'I CH2(COOR)2- CHNa(COOR)2-.CHR'(COOR)2 1NaOH
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EDMOND MALONE (1741-1812)

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