Phloroacetophenone dimethyl ether

Phenylurazole, 381 Phloroacetophenone dimethyl ether, 13 Phloroacetophenone trimethyl ether, 13 Phosgene, 26,94,157 Phosgene Immonium Chloride, 135 Phosphonitrilic chloride, 386-387 Phosphoric acid, 234, 235, 241, 302, 387 Phosphorus pentachloride, 388-389,401, 455,505... 

Preparation by adding an acetic acid solution of nitric acid to an acetonic solution of iodine and phloroacetophenone dimethyl ether at 0° [2066,2935,2936], (75%) [2936],... 

Preparation by reaction of iodine with phloroacetophenone dimethyl ether in methanol in the presence of potassium hydroxide [2937]. 

Ether cleavage (I, 30 3, 7 8). Another example when phloroacetophenone trimethyl ether (I) is heated with aluminum chloride at 110°, it is converted into the dimethyl ether (2). Likewise, the 5-methoxyl group in a polymethoxyflavonc under-... 

The method was applied to the synthesis of evodionol (Table 12.1) by the reaction of the methyl ether of phloroacetophenone shown, to give the chromene in 65% yield (95% on the intermediate used). In the much longer synthesis of evodionol (ref. 39), at the initial step by the Hoesch reaction on 2,2-dimethyl-5,7-dihydroxychroman, the desired 6-acetyl product was the minor one and following benzylation to give the 7-benzyloxy compound, methylation, hydrogenolysis and DDQ oxidation were the required remaining steps. 

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