Blue LED photolytic method for the synthesis of 1,4-dihydropyridine derivatives from benzo [b]thiophene-2-carbaldehyde

• Synthesis of twelve novel 4-(benzo [ b ]thiophen-2-yl)-dihydropyridine-2,3-dicarboxylates by a one-pot approach is demonstrated. • 3 mL of DMSO: H 2 O (1:1) used acts as a solvent and, 5 mol% of Et 3 N acts as additive in the process. • The optimized protocol delivers up to 94 % yield in 60 mins with an easy extraction process. • The reaction demonstrates the efficiency of dimanganese decacarbonyl in catalysing the target molecules. • The methodology is benign, green, sustainable, and facile. This study presents a highly efficient and operationally simple protocol for synthesizing 1,4-dihydropyridine derivatives. The protocol uses an inexpensive and readily available photocatalyst Mn 2 (CO) 10 , which plays a crucial role in the single-pot, four-component reaction involving benzo [ b ]thiophene-2-carbaldehyde, malononitrile, dialkyl acetylene dicarboxylate, and anilines in a blue LED (400–500 nm) photocatalytic technique. The reaction conditions include the use of blue LEDs, a lower catalyst load, and green solvents like dimethyl sulfoxide (DMSO) and water in a 1:1 ratio. The multicomponent photocatalytic approach negates the use of expensive catalysts and the necessity of multi-step routes, in addition to providing better atom economy and an easy work-up process, and it is environmentally benign. The derivatives were effectively synthesized in higher yields and characterized using 1 H NMR, 13 C NMR, and ESI-MS. The obtained 1,4 dihydropyridines also have tremendous capability for biological and pharmacological activities, opening exciting possibilities for future research and applications.