An accurate direct titration method for the determination of anion and cation-active compounds has been developed using new partition end points based on the solubility in organic solvents of complexes formed between anion-active agents and methylene blue, and -active agents and bromophenol blue respectively. cw method has been compared with known methods.IMng the,cours.ei textile processing and in the prosecution of w o n tentilt% shing it is frequently desirable to control low -ticins of such anion-actjve compounds as sodium dk$ -&st indtuf &@on-active compounds such as alkyl pyridinium brbmides? I Methods of determination of such compounds for effective control, should, as far as possible, be simple, straightforward and quick. In addition, particularly in textile processing, the method should be capable of operation &or near the plant. These requirements exclude such methods of the Wing and Puschel:' a to pure blue, in the Hartley and R~d & s method is very illdefined and the accuracy of the determination of the end-point depends largely on the judgement and experience ofthe operator. The Preston method, which excludes any personal factor, was found to apply almost exclusively to compounds of approximate chain length C,, and the end-point for sodium alkyl sulphates was seriously affected by the presence of electrolytes, a defect which invalidated the method for many practical purposes.of determining surface-active agents was thereby developed as described in detail below. Experimental and discussionPromising results were obtained from preliminary experiments in which solutions of sodium oleyl sulphate and cetylpyridinium bromide, each of known approximate strength, were titrated against each other using methylene blue as indicator. As a result of these initial tests the following titration procedure was established. Weigh out accurately such a quantity of the sodium alkyl sulphate or other preparation to be tested as will contain about 0.4 g. of 100% active agent, dissolve in water, transfer to a measuring flask, dilute to I litre and mix well. Call this the test solution. Pipette 25.0 ml. of the test solution into a 10 02. narrow-necked, glass-stoppered bottle and make up to roughly IOO ml. with distilled water. Add 0 . 1 mi. of methylene blue hydrochloride solutiori:(2~dfops) and 50 ml. chloroform, then thoroughly shake the mixture. Titrate the mixture with the standard solution of cetylpyridinium bromide (reagent c), shake vigorously after each addition of titrant and leave to stand for approximately one minute to allow the phases to separate. At the end-point the blue colour of the methylene blue/sodium alkyl sulphate complex is. just discharged from the chloroform into the aqueous phase. Standard titration procedureThe normal procedure adopted was to carry out a preliminary titration by adding the cetylpyridinium bromide in increments of I ml. until the blue colour was discharged from the chloroform. 550'7No analytical dale were available for this sample j the moleculer weight 288 was calculated for CI2 ...

S p a t h , K e s z t l e r . 2725 Ernst S p l t h undDiese Base wurde bereits von I,. C. Craig8) aus Pyridin-P-sulfonsaure iiber das 4-Athoxy-1-oximino-1-[P-pyridyll-butan dargestellt. Unsere Aufgabe war daher, eine Spaltung dieses Racemates vorzunehmen, um eine neue Synthese des 1-Nor-nicotins und den ersten kunstlichen Aufbau des &Nor-nicotins zu bewerkstelligen.Die Spaltung des synthetischen racemischen Nicotins haben A. P i c t e t und A, Rotschy') durch Anwendung der aktiven Weinsauren erzielt. Beim Nor-nicotin haben wir mit diesen Sauren bisher keine guten Erfolge gehabt.Es schien uns vorteilhaft, eine optisch aktive Saure zur Spaltung heranzuziehen, die W i c h der Pikrinsaure, der Pikrolonsaure und verwandten NitroVerbindungen gut krystaltisierende Salze mit den Tabakbasen und anderen Alkaloiden gibt. Hierbei schienen uns die 1-und d-6.6'-Dinitro-2.2'-diphens a u r e n besonders geeignet, die auch schon zur Spaltung einfacher Basen herangezogen worden sind 9).Zur Spaltung des rucem.

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Anthracene used in certain industrial processes must be substantially free from carbazole. No simple method, suitable for the routine determination of the carbazole content of semi-refined and refined technical anthracenes -containing up to about 6 yo and less than 1 yo carbazole respectivelyappears to be available in the literature. An investigation which ultimately led to the development of a suitable method was accordingly undertaken. The results are summarised in the present paper. E x p e r i m e n t a1.From the practical point of view it was considered desirable to devise a method which would be applicable without significant modification to semi-refined (up to about 6 % carbazole) and refined (less than 1 % carbazole) anthracenes, a consideration best met by a colorimetric procedure.A variety of qualitative colour reactions for carbazole is recorded in the literature, many of which use a relatively large proportion of concentrated sulphuric acid as condensing agent. This reagent is impracticable in the present case owing to its charring action on the large proportion of anthracene present. Attention was directed to the possibility of adapting one of these colour reactions to the quantitative determination of carbazole in anthracene using, where possible, condensing agents other than sulphuric acid or alternatively minimum quantities of suitably diluted sulphuric acid.