234 PROCEEDINGS OF THE AMERICAN ACADEMY 



XIX. 



CONTRIBUTIONS FROM THE CHEMICAL LABORATORY OF 



HARVARD COLLEGE. 



ON THE ACTION OF SODIUM MALONIC ESTER ON 

 TRIBROMDINITROBENZOL. 



SECOND PAPER. 



By C. Loring Jackson and W. S. Robinson. 



Presented May 28, 1889. 



In a previous paper * on this subject we were obliged to publish sev- 

 eral results in an unfinished condition, because at the time we saw no 

 chance of being able to continue the work together. Since then, how- 

 ever, unforeseen circumstances have allowed us to go on with the re- 

 search, and in this paper we describe work which fills up most of the 

 gaps in our former publication. 



The most important results contained in this paper may be stated 

 briefly as follows. The reactions by which the bromdinitrophenyl- 

 malonic ester is formed have been made out to be the following : — 



I. C 6 HBr 3 (N0 2 ) 2 + CHNa(COOC 2 H 5 ) 2 = 



NaBr + C G HBr 2 (N0 2 ) 2 CH(COO"C 2 H 5 ) 2 . 



II. C,HBr 2 (N0 2 ) 2 CH(COOC 2 H 5 ) 2 + CHNa(COOC 2 H 6 ) 2 = 



C 6 HBr 2 (N0 2 ) 2 CNa(COOC 2 H 5 ) 2 + CH 2 (COOC 2 H s ) 2 . 



III. C 6 HBr 2 (N0 2 ) 2 CNa(COOC 2 H 5 ) 2 + CH 2 (COOC 2 H.) 2 = 



C 6 H 2 Br(NO,) 2 CNa(COOC 2 H 5 ) 2 + CHBr(COOC 2 H 6 ) 2 . 



IV. CHNa(COOC 2 H.) 2 + H 2 = NaOH + CH 2 (COOC 2 H,) 2 . 



V. CHBr(COOC 2 H 5 ) 2 + NaOH = NaBr + CHOH(COOC 2 H.) 2 . 



The proof of these reactions consisted in the isolation of tartronic acid 

 from the mixture obtained by the saponification of the oily secondary 

 product with hydrochloric acid. 



The action of concentrated hydrochloric acid, or, better, sulphuric 

 acid of specific gravity 1.44, upon the bromdinitrophenylmalonic ester 



* These Proceedings, xxiv. 1. 



