132 B-134 A.] 



KETOCOUMARAN 



231 



2995), the dialkyl ester of which, on 

 treatment with sodium in benzene solu- 

 tion, yields ketocoumarancar boxy lie 

 ester. On treating 1 the ester with alkali 

 ketocoumaran is formed (Friedlander, 

 Ber. 32, 1868). 



[C.] From phenol [60] and acetic acid 

 [Vol. II] through phenoxyacetic acid 

 by the interaction of chloracetic acid 

 (or ester) and sodium phenoxide (Heintz, 

 Jahresber. 185 9, 361 ; Hantzsch, Ber. 

 19, 1296; Giacosa, Journ. pr. Ch. [2] 

 19, 396 ; Fritzsche, Ibid. 20, 269). 

 Phenoxyacetic acid, on heating with 

 dehydrating agents, gives ketocoumaran 

 (Stoermer, Ber. 30, 1712 j Stoermer 

 and Bartsch, Ber. 33, 3175). 



Schmid, Journ. pr. Ch. [2] 25, 82; 

 Michael, Am. Ch. Journ. 5, 434). 

 /3-Methylumbelliferone gives resaceto- 

 phenone on fusion with potash (v. Pech- 

 mann and Duisberg, loc. cit. 2123). 



Or resorcinol and sodio-acetoacetic 

 ester condense in alcoholic solution to 

 give a carboxylic acid which yields /3- 

 methylumbelliferone on heating (Mi- 

 chael, Journ. pr. Ch. [2] 35, 454 ; 37, 

 470; v. Pechmann, Ann. 261, 169). 



Resorcinol and citric acid [Vol. II] 

 also give /3-methylumbelliferone on 

 heating with sulphuric acid (Witten- 

 berg, Journ. pr. Ch. [2] 24, 125; v. 

 Pechmann, Ber. 17, 931). 



133. Pseoiiol ; Resacetophenone 



Methyl Ether ; 2-Hydroxy-4-Meth- 



oxyacetophenone ; E than oy 1-2 : 4- 



Plieneclicl 4-Metliyl Ether. 



CO.CH 3 

 OH 



O.CH 3 



CO . CH 3 

 :O 



:H 2 

 O.CH, 



NATURAL SOURCE. 



In the root bark of Paonia moutan from 

 Japan and China (Martin and Yagi, 

 Arch. Pharm. 213, 335 ; Nagai, Ber. 

 24, 2847)- 



SYNTHETICAL PROCESSES. 



[A.] Resorcinol [70] and acetic acid 

 [Vol. II] when heated with zinc 

 chloride, or resorcinol alone, when heated 

 with the latter, gives resacetophenone = 

 ethanoyl-2 : 4-phenediol (Nencki and 

 Sieber, Journ. pr. Ch. [2] 23, 147). 

 The latter is methylated by methyl 

 iodide [13] and potassium hydroxide in 

 methyl alcoholic solution (Tahara, Ber. 

 24, 2460). 



Or from resorcinol and acetoacetic ester 

 [Vol. II] through /3-methylumbelli- 

 ferone by treating a mixture in the 

 cold with sulphuric acid, or by heating 

 with zinc chloride (v. Pechmann and 

 Duisberg, Ber. 16, 2119; Ann. 261, 169; 



134. Hydrocotoin ; 2:4: 6-Trihy- 

 droxybenzophenone Dimethyl Ether ; 

 Benzocotoin ; Benzoylphloroglucinol 



Dimethyl Ether ; 2 : 4-Methoxy-6- 

 Hydroxybenzophenone. 



CO.C B H, 



OCH, 



OCH 3 



NATURAL SOURCE. 



In coto bark from Bolivia (Jobst 

 and Hesse, 199, 57). The botanical 

 origin is unknown, but the tree is 

 probably Lauraceous or Monimiaceous. 



SYNTHETICAL PROCESS. 



[A.] From phloroglucinol [86], ben- 

 zoic acid [Vol. II] through benzoyl 

 chloride, and methyl alcohol [13]. The 

 dimethyl ether of phloroglucmol is pre- 

 pared by passing hydrogen chloride 

 through a methyl alcoholic solution of 

 phloroglucmol (Will, Ber. 21, 603). The 

 dimethyl ether is benzoylated by ben- 

 zoyl chloride in presence of alkali, and 

 the benzoyl-dimethyl ether heated with 

 benzoyl chloride in benzene solution in 

 presence of zinc chloride. The benzoyl- 

 hydrocotom thus formed gives hydro- 

 cotoin on hydrolysis (Pollak, Monats. 

 18, 736). 



