Synthesis and Characterization of a New Class of Flavylium Salts; a Facile Route to the 2-(2-Acetoxyphenyl)-4-methylidene-4H-1-benzopyran Derivatives. X-Ray Crystal Structure of 2-(2-Acetoxy-5-methylphenyl)-4,6-dimethyl-1-benzopyranylium Pentachlorostannate: Supporting Evidence of Chl...

Article abstract of DOI:10.1002/hlca.19880710416

Several mixtures of compounds 1 and 2 were synthesized from SnCl4 and p-substituted aryl acetates.Separation of 1/2 was achieved either by treatment of the mixture with MeCN prviding the pure complex 1 or by reaction with MeCOCl leading selectively to a new class of flavylium salts 3 or 4.The structure of 2-(2-acetoxy-5-methylphenyl)-4,6-dimethyl-1-benzopyranylium pentachlorostannate (3a) was determined by single-crystal X-ray diffraction.The Sn-atoms are hexacoordinated in the dimeric unit Sn2Cl10^2- through Cl bridging.Furthermore, we report the easy preparation of 1-benzopyran derivatives starting from the salts 3.