Novel and Efficient One-Step Parallel Synthesis of Dibenzopyranones via Suzuki−Miyaura Cross Coupling

Abstract

Microwave promoted novel and efficient one-step parallel synthesis of dibenzopyranones and heterocyclic analogues from bromo arylcarboxylates and o-hydroxyarylboronic acids via Suzuki-Miyaura cross coupling reaction is described. Spontaneous lactonization gave dibenzopyranones and heterocyclic analogues bearing electron donating and withdrawing groups on both aromatic rings in good to excellent yields.

Silver-Catalyzed C(sp2)–H Functionalization/C–O Cyclization Reaction at Room Temperature

“…GCMS (EI) m/z 271 (M) + . 20 : According to the general procedure, the reaction mixture was stirred at room temperature for 24 h. The product was isolated by flash chromatography 124.6, 124.4, 123.8, 122.4, 117.5, 117.4.…”

A Green Protocol for the Bromination and Iodination of the Aromatic Compounds using H5IO6/NaBr and H5IO6/NaI in the Water

“…1,2 Due to the potential utilization of aryl bromides and iodides in the synthesis of aryl esters, aryl olefins and other useful compounds and their wide applications in medicine and biochemitry, [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] bromination and iodination of aromatic compounds have been the subject of numerous studies. Recently, the oxidative halogenation of organic compounds by halides have emerged as an important alternative for the synthesis of such haloderivatives.…”

19F NMR study of ligand dynamics in carboxylate-bridged diiron(ii) complexes supported by a macrocyclic ligand

“…Thus, the new synthesis required (2-hydroxy-5-methylphenyl)boronic acid ( L2a ), which was prepared from the commercially available (2-methoxy-5-methylphenyl)boronic acid following a literature procedure. 18 The Suzuki-coupling between L1 and L2a yielded the desired product, L3a , in 61–80% yield using [Pd(PPh 3 ) 4 ] as the catalyst. The last step of the synthesis was unmodified.…”