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Herein, we report a new method for the synthesis of functionalized pyrrole and isoquinoline derivatives using isoxazole based precursors. The reaction proceeds through the ring opening and ring closing cascade mechanism (ROCC) to afford pyrrole or isoquinoline derivatives in good to excellent yields under very mild experimental conditions. Product outcome relies on the strategic placement of different substituents on the isoxazole moiety. The present method is also applicable to synthesize functionalized isoquinolone derivatives. [ABSTRACT FROM AUTHOR]

An efficient, facile, and clean synthesis of various 3‐hydroxy‐chromones (3‐hydroxy‐4H‐chromene‐4‐ones) via enamino ketone followed by cyclization using m‐chloroperbenzoic acid (MCPBA) has been described. The significant features of this method include simple method, high purity and excellent regio‐selectivity of the products. This is the first report for the two step one pot synthesis of 3‐hydroxyl chromone using MCPBA. [ABSTRACT FROM AUTHOR]

A new regioselective method for the synthesis of 3-(methylthio)-4H-chromen-4-one and 3-(phenylthio)-4H-chromen-4-one derivatives has been developed. The reaction between o-hydroxy-phenyl-functionalized enaminones and methylsulfinyl derivatives using T3P® gave good yields of chromone thioether derivatives. The reaction proceeds via domino chromone ring construction and C(sp2)–H bond sulfenylation under transition-metal-free conditions. [ABSTRACT FROM AUTHOR]

An efficient synthesis of 4H-chromene-4-ones via enamino ketones, with cyclization by using T3P® under microwave heating is described. This is the first report for the synthesis of chromones by using T3P®. Significant features of this method include short reaction times and high-purity products. [ABSTRACT FROM AUTHOR]

An efficient method for the preparation of chromone based $$\upalpha $$ -amino acid derivatives by alkylation of glycinate schiff base with 3-bromomethyl chromone as well as 2-bromomethyl chromone has been described. Using this method, 2-amino-3-(4-oxo-2-chromenyl)propanoic acid and 2-amino-3-(4-oxo-3-chromenyl)propanoic acid, two novel chromone-amino acid conjugates have been prepared. Furthermore, the separation of chromone amino acid enantiomers by chiral column chromatography was accomplished. Graphical Abstract : Synopsis: An efficient method for the preparation of chromone based $$\upalpha $$ -amino acid derivatives by alkylation of glycinate schiff base with 3-bromomethyl chromone as well as 2-bromomethyl chromone has been described. These conjugates can be considered as analogues of phenyl alanine where phenyl group has been replaced by chromone moiety. [ABSTRACT FROM AUTHOR]