Permanence of the Grignard Reagent

for the chemists of America andelsewhere is ofthe utmost im- portance. This work has been ... The heart of any abstract journal is its index. Chemistr...
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Mar., 1922

THE JOURNAL OF INDUXTRIAL A N D ENGINEERING CHEMISTRY

The Formula Index Editor of the Journal of Industrial and Engineering Chemistry: The work that Chemical Abstracts has been doing and is doing for the chemists of America and elsewhere is of the utmost importance. This work has been developing without a backward step from its start in 1907, until just recently. However, the action of the directors of the SOCIETY in stopping work upon the formula index to Chemical Abstracts for 1921 is very much to be deplored, as it curtails the usefulness of the journal. I wish to take this occasion to protest against this action and to ask other chemists interested to file a similar protest. The reasons which lead to my opinion are the following: The heart of any abstract journal is its index. Chemistry is now so complex that it is utterly impossible to have a simple index. Those responsible for Chemical Abstracts realized this and, beginning with the Decennial Index, evolved the most scientific nomenclature yet proposed for such a n index. This index is a very excellent one but neither i t nor any other complete word index can be used without considerable study and experience with the principles involved. On the other hand, a formula index especially for organic compounds is extraordinarily simple to use. It furthermore gives more accurate and quicker information as to the presence of a given compound in a n index than will a word index. I trust that some way will be found to restore the formula index to Chemical Abstracts. It would be very much better to or to economize in other direcincrease the dues of the SOCIETY tions rather than to drop this formula index. As a matter of fact, a formula index ought to be prepared as a supplement to the Decennial Index, as soon as possible. R. NORRISSHREVE 43 FIFTHAVE. NEW YORK,N. Y. January 18, 1922

Permanence of the Grignard Reagent [PRELIMINARY NOTE]

I n connection with a series of quantitative studies on the Grignard reagent, particularly the determination of the optimum condition for the formation of this reagent, it was considered desirable t o undertake investigations which it is hoped will extend the general usefulness of the reagent, more especially where reasonably large quantities are used. The Grignard reagent is generally prepared by adding a solution of the appropriate R X compound in absolute ether to magnesium turnings. The RMgX compound so formed is quite sensitive to air, a small amount of moisture, in particular, decomposing a relatively large amount of the reagent. Partly for this reason and the uncertainty concerning its stability, the reagent is very conveniently used directly after preparation. One rarely hears of “stock” Grignard reagent. It has been found that ethyl magnesium bromide in ether and phenyl magnesium bromide in ether, when protected from the air, are stable after a period of two months. Parallel experiments with ethyl magnesium bromide in the light and in the dark have shown that daylight is without influence on the strength of the solution. The investigation is being extended to a variety of typical RMgX compounds, some in highly concentrated ethereal solutions, over a longer time period. A study is also being made of pastes, of so-called “individual” compounds, and of solvents other than ether, with the intention of decreasing the fire hazard and the comparatively large expense attendant on the use of ether as a medium. HENRYGILMAN H. MEYERS CHARLES DEPARTMENT OF CHEMISTRY

IOWA STATE COLLEGE, AMES,IOWA December 23, 1921

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Contamination by Aluminium in Analytical Work Editor of the Journal of Industrial and Engineering Chemistry: Considerable trouble has been met in the courses in qualitative analysis a t the University of Illinois on account of the appearance of decidedly appreciable amounts of aluminium during the course of the procedure. It was found to come from two rather unexpected sources. One source was the filter papers used. These papers were purchased for the usual “qualitative” grade, and behaved very satisfactorily so far as holding fine precipitates was concerned. Upon filtering acid solutions, however, enough aluminium was leached out to give decided tests for this element. Sulfates and traces of iron were also detected. Quantitative examination showed that, as a n average of several determinations, a 10-cm. paper contained 3 mg. of aluminium and iron (computed as AlnOa and FezOs), to say nothing of considerable amounts of acid-soluble silica. The source of this rontamination can only be conjectured. The presence of the aluminium and sulfate suggested alum, which might have come by the use for filter stock of trimmings from paper mills and binderies, which would contain alum as sizing. The acid-soluble silica, on the other hand, indicates clay, which is sometimes used as a filler for “weighting” paper. A second source of aluminium was found in the porcelain evaporating dishes used. Digesting acid solutions in the brand of dish which has been used in this laboratory for the past two or three years results in the solution of various amounts of aluminium and silica, particularly if the glaze has been broken by previous use. It was found that more than 50 per cent of the dishes in the student cupboards would show R mark if a graphite pencil were drawn across their interior surfaces. As an extreme example, one badly pitted dish lost 6 . 9 mg. upon boiling 6 N HCl in it for 15 min. As a substitute for these dishes, the classes in qualitative analysis have been using small beakers, which approximate the familiar “Pyrex” cooking vessels in composition. These were found very satisfactory, and it may be interesting t o note that the indications are that the breakage accounts of the students will be reduced somewhat by their use. These experiences are paqsed along to the rest of the chemical brotherhood “for the good of the order.” J. H. REEDY CHEMICAL LABORATORY UNIVsRSITY OF ILLINOIS URBANA, ILLINOIS n‘ovember 16, 1921

Holland’s Tariff Situation Editor of the Journal of Industrial and Engineering Chemistry: In reading Mr. Watson Davis’ interesting article on conditions 14 (1922), 731, I note certain somein Europe [THISJOURNAL, what erroneous statements. It is true, as Mr. Davis states, that Switzerland and Holland, as neutral border states, have to face severe competition. What Switzerland may have done to overcome this drawback I do not know, but so far Holland has not “raised stringent tariff barriers to prevent a flood of goods from Germany, Austria, and other low-wage-plane countries.” Many people in Holland are of the opinion that only such a barrier, in the form of a protective tariff bill, can save our trade and industry from gradual economic starvation. It is not my intention to discuss this question here, but simply to call attention to a misunderstanding of our condition, In my opinion, Holland’s economic breakdown as a consequence of Germany’s industrial and financial policy toward her is not a mere phantom, but a real fact. H. BAUCKE KONING& BIENFAIT 104, AMSTERDAM, HOLLAND DA COSTAKADE January 19, 1922