2-Benzopyrylium salts

Effect and Spectroscopic Analysis of Solutions in Trychloratsetylpyrogallol Synthesis

“…Later K. Fries and V. Pfaffendorfs synthesized phenylchloroacetate by heating a mixture of phenol and chloroacetyl chloride at 135 °С for 5 h and regrouping it at 150 °С in the presence of AlCl3; they found that only 2-hydroxyphenacyl chloride was formed as a result of the reaction: G. N. Dorofenko and E. N. Sodikov [8] also studied the reaction of the chloroacetylation of phenol. Unlike the above authors, they heated phenol and chloroacetyl chloride Buy-Khoi and co-workers [3] carried out the chloroacetylation reaction of durol in the presence of AlCI3.…”

“…Later K. Fries and V. Pfaffendorfs synthesized phenylchloroacetate by heating a mixture of phenol and chloroacetyl chloride at 135 °С for 5 h and regrouping it at 150 °С in the presence of AlCl3; they found that only 2-hydroxyphenacyl chloride was formed as a result of the reaction: G. N. Dorofenko and E. N. Sodikov [8] also studied the reaction of the chloroacetylation of phenol. Unlike the above authors, they heated phenol and chloroacetyl chloride Fries and A. Fink practically proved that in the reaction of chloroacetylation of phenols, O-acylation reaction takes place first, after which complex ether is formed, and then regrouping occurs to form the S-acylation product, ketone; later on, this reaction was named "Fries rearrangement" [6,7].…”

“…. Dorofenko and E. N. Sodikov[8] also studied the reaction of the chloroacetylation of phenol. Unlike the above authors, they heated phenol and chloroacetyl chloride in equimolecular amounts without a catalyst (14 h), which resulted in the formation of the O-acylation product phenylchloroacetate with 79% yield.Considering the above information, the o-chloroacetylation reaction of triatomic phenols was studied.…”

A Simple and Efficient Synthesis of Substituted 2,2′-Bithiophene and 2,2′:5′,2″-Terthiophene

“…Ketones 2a – e were obtained by the reaction of thiophene and the corresponding carboxylic acids 1a – e in the presence of trifluoroacetic anhydride …”