DUREN

duren, a town of germany, in the prussian rhine province, on the right bank of the roer, 19 m. e. from aix-la-chapelle on the main line of railway to cologne. pop. (1905) 29,270. it has two protestant and six roman catholic churches, among the latter the gothic st annakirche, said to contain a portion of the head of the saint, to the shrine of which frequent pilgrimages are made. there are several high grade schools, monuments to the emperor william i., bismarck and moltke, and, in the town-hall, a collection of antiquities. it is the seat of considerable manufactures, notably cloth, paper, flax-spinning, carpet, artificial wool, sugar, iron wares and needles. duren derives its name, not, as was at one time believed, from the _marcodurum_ of the ubii, mentioned in tacitus, but from the _dura_ or _duria_, assemblies held by the carolingians in the 8th century. it received civic rights early in the 13th century. hypothecated by the emperor frederick ii. to count william of julich, it became incorporated with the duchy of that name, and with it passed to prussia in 1816. durene (1.2.4.5 tetramethyl benzene) c6h2(ch3)4, a hydro-carbon which has been recognized as a constituent of coal-tar. it may be prepared by the action of methyl iodide on brom-pseudocumene or 4.6 dibrom metaxylene, in the presence of sodium; or by the action of methyl chloride on toluene, in the presence of anhydrous aluminium chloride. it crystallizes in plates, having a camphor-like smell, melting at 79-80 deg. c. and boiling at 189-191 deg. c. it is easily soluble in alcohol, ether and benzene, and sublimes slowly at ordinary temperature. on oxidation with chromic acid mixture, it is completely decomposed into carbon dioxide and acetic acid; nitric acid oxidizes it to durylic and cumidic acids [c6h2.(ch3)2.(cooh)2].