A facile and efficient synthetic approach to various valuable 3-aryl- and 3-aroylcoumarins by the direct arylation and aroylation of coumarins with glyoxals in a metal-free manner is presented. The aryl glyoxal is for the first time recognized to serve as an aryl surrogate in addition to its role as an aroyl transfer reagent via a simple switch in reaction conditions. The approach accommodates a broad substrate scope and high yields of the two types of cross-coupling reactions starting from identical starting materials.

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A simple, new two‐step procedure for the synthesis of novel tricyclic pyrrolo[2,1‐a]isoquinoline derivatives is described. The initially prepared polysubstituted pyrroles obtained via the four‐component condensation of arylglyoxals, cyclic 1,3‐dicarbonyls, aminoacetaldehyde dimethyl acetal, and β‐keto esters subsequently underwent intramolecular acid‐catalyzed cyclization to the desired products in moderate to good yields.

A one-pot approach to the synthesis of new spirocyclic-dihydropyrazine-2-(1H) ones is described. The Ugi four-component condensation of cycloalkanones, carboxylic acids, cyclohexyl isocyanide and aminoacetaldehyde dimethyl acetal followed by acid-catalyzed deprotection-cyclization afforded the desired products in moderate to good yields.