Chromone-2-carbonyl chlorides synthesis

Chromone-2-carbaldehyde, 3-methyl-synthesis, 3, 709 Chromonecarbaldehydes Knoevenagel condensation, 3, 711 Chromone-3-carbaldehydes mass spectra, 3, 615 oxidation, 3, 709 reactions, 3, 712 Schiff bases, 3, 712 synthesis, 3, 821 Chromone-2-carbonyl chloride Grignard reaction, 3, 711 Chromonecarboxamide, N-tetrazolyl-antiallergic activity, 3, 707 Chromone-2-carboxylic acid, 3-chloro-ethyl ester... 

The one-pot synthesis of 2-substituted-3-carboxychromones is readily attained by the reaction of 3-oxo-3-(2,6-di luorophenyl)propanoates and acyl chlorides (13CC5313) and of 3-[2-(methoxymethoxy)phenyl]propio-lates and aldehydes followed by DDQ oxidation of the formed chroma-nones (13T647), via transition metal-free approaches. Palladium(II) -catalyzed cascade carbonylative cyclization of 2-bromophenols and terminal alkenes gives chromones 44 in moderate to good yields. Variation on the amine used in the catalytic system led to aurones 45 as major products (Scheme 74) (13TL1802). 

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