Divergent Syntheses of Spiroindanones and 2-Substituted 1-Indanones by Ruthenium-Catalyzed Tandem Coupling and Cyclization of Aromatic Acids with α,β-Unsaturated Ketones

Abstract

The one-step strategy for the facile syntheses of structurally diverse 1-indanones in moderate to good isolated yields was developed via a ruthenium-catalyzed tandem coupling and cyclization of simple aromatic acids with α,β-unsaturated ketones. The tandem cyclization involves one-pot sequential reactions of C−H activation, conjugate addition, Dieckmann condensation, Michael addition, intramolecular Aldol reaction, or hydrolysis. Switchable access to spiroindanones and 2substituted 1-indanones could be achieved by manganese additive and H 2 O. Mn(II) additive is found to play an important role in this transformation, and a trace amount of water can promote the formation of 2-substituted 1-indanones. This process features the one-pot efficient construction of multiple C−C bonds, high step-economy, commercially available starting materials, and a broad substrate scope.

Aldehyde as a Traceless Directing Group for Regioselective C–H Alkylation Catalyzed by Rhodium(III) in Air

“…As part of our program on the conjugate addition of aryl C–H bond to unsaturated electrophiles, herein, we report the application of aldehydes as traceless directing groups to access regioselectively alkylated arenes via the direct addition of C–H bonds to acrylates or acrylic acids, followed by the decarbonylation under aerobic atmospheric conditions. Notably, the developed reaction was insensitive to the air and moisture, and a trace amount of water was found to be beneficial to the reaction.…”

Ruthenium-catalyzed C–H bond functionalization in cascade and one-pot transformations

“…Excellent diastereoselectivities for the final indenofuranone products were observed, which was likely a consequence of steric factors. Examples combining ruthenium-catalyzed C-H bond functionalizations and manganese-mediated cyclizations were reported by Shi and co-workers [109]. Similar to the previous example, benzoic acids were employed as substrates for carboxylate-directed C-H bond alkylations with ,-unsaturated olefins.…”

Divergent g-C3N4-catalyzed Reactions of Quinoxalin-2(1H)-ones with N-Aryl Glycines under Visible Light: Solvent-Controlled Hydroaminomethylation and Annulation

“…Divergent synthesis is of great significance in organic synthetic chemistry , owing to the rapid acquisition of structurally diverse chemical scaffolds from the same starting materials, − which has also been considered as a highly attractive synthetic strategy for the synthesis of heterocyclic compounds. , Generally, different products could be generated from the identical starting materials through the variation of functional groups, − catalysts, solvents, − additives, − and ligands to switch the reaction pathways. This strategy provides an indispensable route to build a molecular library with maximum scaffold diversity. − Therefore, the divergent synthesis of various scaffolds from easily available starting materials is urgently pursued and expected.…”