An efficient sequential four-component reaction of chromone carbaldehydes, Meldrum's acid, 4-hydroxyl coumarin or 6-methyl-4-hydroxyl-pyrone and primary alcohols is reported which leads to 5a-i in aqueous media. Replacing the primary alcohol with isopropyl alcohol and tert-butyl alcohol results in different products 10 and 11. The environmentally friendly features, good to high yields and easy work-up are advantages of this approach.

Novel analogs of 2-pyridone-3-carboxylic acids 4a-l have been prepared by the three-component reaction of 3-formyl chromone, Meldrum's acid, and primary amines in the presence of a catalytic amount of diammonium hydrogen phosphate in water. Good-to-high yields, easy work-up, and an environmentally friendly profile are the advantages of this method for the synthesis of 2-pyridone-3-carboxylic acid derivatives.

Synthesis of Functionalized Chromones Through Sequential Reactions in Aqueous Media. -The sequential four-component reaction of chromone aldehydes (I), meldrum's acid (II), coumarin (IV) or pyrone (VI) in the presence of primary alcohols (III) leads to coupled products (V) and (VII), respectively. Replacing the primary alcohol with iPrOH or tBuOH results in the formation of products (VIII) and (IX), respectively. -(MEHRPARVAR, S.; BALALAIE*, S.; RABBANIZADEH, M.; ROMINGER, F.; GHABRAIE, E.; Org. Biomol. Chem. 12 (2014) 30, 5757-5765, http://dx.