Coordinative role of alkali cations in organic synthesis. 3. Selective methylations of 5-hydroxy-2-hydroxymethyl-.gamma.-pyrone

Abstract

If methylene chloride Is used as solvent in this reaction, the major product is chloroacetonitrlle, which was characterized by its NMR and mass spectra. ( 14) S.

Kojic acid in organic synthesis

“…Sibi et al 199 described the conversion of pyrones 315 to pyrans 317, a structural unit present in compounds with significant biological activity. Enantioselective radical additions to pyrones 315 were carried out in the presence of 30 mol% of 316 as a catalyst and RI using Bu Other reactions of KA are also reported in the literature, such as acylation and benzoylation, 200−205 cyanoethylation, 206 esterification, 207−216 methylation, 217,218 mesylation of KA, 219 bromination, 220 thiocyanation, 221 cyanidation, 222 glucosylation of KA, 223,224 reaction of KA with acrylonitrile and acrylic ester, 225,226 diethyl malonate, 227 s -butyl mercaptan, 228 glucose pentaacetate, 229 ethyl levulinate 230 and nucleophilic substitution reactions, 231 formation of KA diacetate, 232 Betti reaction of KA, 233 synthesis of selenocyanato derivatives of KA, 234 oxidation of the side chain in KA, 235 and Hoesch reaction of KA. 236…”