Base-Promoted One-Pot\nFour-Component Domino Strategy\nInvolving Aldehydes and Ketones to Access Multifunctionalized Dihydropyridinones

The synthesis of multifunctionalized dihydropyridinones\nfrom aldehydes\nand ketones involves at least a three-step process, making route shortening\na challenging task, especially in achieving a one-pot four-component\nsynthesis via aldehydes and ketones precondensation. Herein, we discovered\na [1 + 2 + 1 + 2] four-component domino cyclization reaction, a novel\nconcept in 4CRs with commercially available ketones and aldehydes,\nwhich by initially combining aldehydes and ketones with Meldrum’s\nacid and ammonium acetate (NH<sub>4</sub>OAc), respectively, they\ngive dihydropyridones (>110 examples). This transformation features\ninexpensive additives and readily available starting materials, making\nit appropriate for rapid access to relevant pharmaceutical molecules\ncontaining dihydropyridinone-derived heterocycles. Also these compounds\ncan be conveniently converted into trisubstituted and tetrasubstituted\npyridines.