Microwave‐Assisted Domino Palladium Catalysis in Water: A Diverse Synthesis of 3,3′‐Disubstituted Heterocyclic Compounds

Abstract

An environmentally benign microwave‐assisted domino [Pd]‐catalyzed reaction, for the efficient and diverse synthesis of 3,3′‐disubstituted indolines, oxindoles, and dihydrobenzofurans, is presented. Significantly, water served as the sole green solvent and the strategy displayed an excellent functional‐group tolerance. Remarkably, the process was also amenable to unmasked functional groups and furnished the products, in very good to almost quantitative yields.

Dual C‐C Bond Forming Heck and Sonogashira Couplings Followed by Hydroarylation: Synthesis of Tricyclic Frameworks

“…Thus, the synthetic plan was initiated from allyl ortho ‐iodophenyl ether 1 a and the coupling partner phenylacetylene 2 a . Consequently, dihydrobenzofuran 3 aa was synthesized using our previously established microwave irradiation conditions, in aqueous medium [i. e. Pd 2 (dba) 3 (1 mol%), benzyltriethylammonium chloride (BTEAC, 1 equiv), 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU, 3 equiv), MW, 100 °C, 15 min] . Now, the screening study has begun on the crude reaction mixture of dihydrobenzofuran 3 aa through acid promoted intramolecular cyclization.…”

New Dual-Functional and Reusable Bimetallic Y2ZnO4 Nanocatalyst for Organic Transformation under Microwave/Green Conditions

“…Owing to these attractive features, microwave-assisted functional group transformations and chemical synthesis gained tremendous interest in the field of green and sustainable chemistry. On the other hand, avoiding toxic and volatile organic solvents is the most acceptable practice in green chemical synthesis, and accordingly, development of solvent-free reaction conditions is a highly desirable process in terms of cost and environmental benefits. − …”

Novel ultra-small Pd NPs on SOS spheres: a new catalyst for domino intramolecular Heck and intermolecular Sonogashira couplings

“…12,13 We have also established the efficient synthesis of benzofurans, oxindoles, and indolines under homogenous catalysis. 14,15 Domino reactions have been proven to be incredible synthetic organic reactions in chemistry as they permit the formation of at least two or more bonds in a single operation. To the best of our knowledge, there are no reports on domino reactions via heterogeneous catalysis using sub-molar quantities of the catalyst.…”