114 



SCIENCE 



[N. S. Vol. XL. No. 1020 



The Salts of the Acridines: L. H. Cone. 



Free radicals analogous to triphenylmethyl have 

 been isolated from the salts of diphenylacridol and 

 N-methylphenylaeridol. These free radicals be- 

 have in every way analogous to triphenylmethyl, 

 yielding peroxides on exposure to air and adding 

 on halogens, etc. From these facts the conclusion 

 is drawn that in all probability the salts of the 

 acridines are quinocarborium salts analogous to 

 the quinonoid form of triphenylchloromethane 

 from which triphenylmethyl comes, at least in 

 part. This conclusion is at variance with the ac- 

 cepted ammonium formulation of the salts of the 

 acridines. 

 The Action, of Halogen on 4-N'itro-in-Cresol : L. 



Chas'. Eaifoed. 



The experiments of Kehrmann and Tichvinsky 

 on the chlorination of 4-nitro-m-eresol have been 

 repeated, and the experiments varied so as to use 

 pure chlorine as well as mixtures with carbon di- 

 oxide. Instead of 6-chloT-4-nitro-m-oresol only, as 

 reported by K. and T., 75 per cent, of the product 

 was found to 2-chlor-4-nitro-m-cresol, and but 5-10 

 per cent, of the compound with chlorine para to 

 methyl. Chlorination with mixtures furnishing 

 so-called nascent chlorine, gave nothing but 2-6- 

 dichlor-4-nitro-m-cresol. 

 A Simple Method for the Determination of the 



Accuracy of the Conductance Data of Organic 



Electrolytes: C. G. Deeick. 



The use of the linear plotting functions to test 

 the precision and presence of constant errors in 

 conductance data has been found unsatisfactory 

 in the hands of beginning research men. In the 

 case of the weak and transition electrolytes, the 

 calculation of the molar conductance at zero eom- 

 eentration has been found to be a very satisfac- 

 tory criterion for both precision and constant 

 errors of the conductance data of organic electro- 

 lytes. Its sensitiveness may be varied and no me- 

 chanical skill is necessary in its application. Its 

 application to existing measurements on the con- 

 ductance data of weak electrolytes shows that these 

 data are very inaccurate as a rule. 



The Ionization Constant of Pyroracemic Acids: C. 



G. Deeick and' St. Elmo Brady. 



The unsatisfactoriness of the use of the ordi- 

 nary criteria of purity of organic compounds is 

 emphasized. Organic chemists are urged to use 

 additional criteria such as the ionization con- 

 stants. This statement was emphasized by the 



measurements of the conductance data on pyro- 

 racemic acid. Also the application of its calcu- 

 lated molar conductance at zero concentration as 

 a criterion of the precision and constant errors in 

 the measurements was illustrated. 



On Cyanoacetic Ester: John C. Hessler. 



The alkylation of cyanoacetic ester by means of 

 sodium ethylate and alkyl haloids gives large 

 amounts of di-alkyl cyanoacetic ester. Methyl 

 iodide gives 12.3 per cent., ethyl iodide 30 per 

 cent., ethyl bromide 28 per cent., normal propyl 

 iodide 35 per cent., isoamyl iodide 28 per cent., of 

 the di-alkyl cyanoacetic ester. The heating of 

 these di-alkyl esters with concentrated hydro- 

 chloric acid in sealed tubes is an unsatisfactory 

 method of saponification. Caustic potash in pure 

 methyl alcohol reacts ideally in the cold, giving 

 the di-alkyl cyanoacetic acids in theoretical quan- 

 tity. The salts of these acids, and their acid 

 chlorides, amides, anilides, etc., have been pre- 

 pared. 



The Conrad-Limpoch reaction has also been 

 carried out in methyl alcoholic solution. The 

 yields are small, yet the alcohol is as anhydrous 

 as it seems possible to make it. The products are 

 methyl esters, not ethyl esters, owing to an ex- 

 change with the methyl group of the alcohol. 

 When benzyl chloride is used in place of the alkyl 

 haloids a large amount of di-benzyl cyanoacetic 

 methyl ester is obtained. This is a beautifully 

 crystalline solid melting at 78°-79° C. 



The investigation is being continued with the 

 use of propyl, isobutyl and isoamyl alcohols as sol- 

 vents. 



On Thursday a symposium on the teaching of 

 elementary organic chemistry was held with the 

 following papers: 

 I. Theory of Elementary Organic Chemistry: 

 J. B. Allan, Chairman. 



' ' The Teaching of Elementary Organic 

 Chemistry without the Use of Atomic 

 and Molecular Hypotheses. ' ' 

 II. Theory of Organic Chemistry for Graduate 

 Students: E. K. Eenshaw. 



"What shall be the Character of the Ad- 

 vanced Instruction in Organic Chemis- 

 try?" 

 III. Laboratory Teaching of Organic Chemistry: 

 ■ L. W. Jones. 



' ' The Teaching of Organic Chemistry in the 

 Laboratory. ' ' 



Chaeles L. Parsons, 



Secretary 



