ACETO ACETIC ESTER 47 



If resorciu, Ce H4 (0H)2, is used /9methyl-umbelliferone, 



Ca H 0H<^^ (CH3) : CH, 



is formed which when treated with potassium hydroxid gives resaceto- 

 phenon, CeHj (0H)2 CO CH3. The methyl ester and the carboxylic acid 

 of /Jmethyl-umbelliferone were formed. a-^'9-Di-methyl-umbelliferone, 



Ce H3 (OH) <g ^^^3): C^CH3) 

 was formed from resorcin and dimethyl-acetoactic ester. Metatoluene-y9- 

 methyl-coumarin, Ce H3 CH3<^ ___^^* p^ was formed from para- 

 cresol, C6 H4 OH CH3, and acetoacetic ester. 



PERKIN, Jr., W. H., 1883. 



Ber. 16, 2 136-2140 ; J. Chem. Soc. 46, 64. 



Action of Ethylene Bromid on Acetoacetic and Benzoyl=acetic Esters. 



From acetoacetic ester, ethylene bromid and sodium, aceto-tri- 



CH3 

 I 



CO 

 I CH2 



methylene carboxylic ester, C < I , is formed, which boils at 193° to 



I CH2 

 CO2 C2 H5 



195° The acid and the silver salt were obtained. Benzoyl- trimethy- 

 lene carboxylic ester and acid and benzoyl-trimethylene were also 

 produced. 



GEUTHER, A., 1883. 



Ann. Chem. 219, 119-128 ; J. Cheni. Soc. 46, 836; Ber. 16, 2290 ; 

 Jsb. Chem. 1883, 1065. 



Constitution of Acetoacetic Esters and of Benzene. 



The formation of tri-brom- acetoacetic ester by Wedel and the forma- 

 tion of acetoacetic ester from acetic ester are cited as proof of the 

 formula CH3 COH : C H CO2 C2 H, and against CH2 : COH CH2 CO2 



