Rhodium-Catalyzed Cascade Reaction: Aryl Addition/Intramolecular Esterification to Access 3-Aryl and 3-Alkenyl Phthalides

Synthesis of Benzodioxepinones and Benzoxazepinones via Tandem Oxidation and Iodolactonization of 2-O/N-tethered Alkenyl Benzaldehyde Mediated by CuI/TBHP

An efficient methodology for the synthesis of halogenated benzodioxepinones and benzoxazecinones has been developed via tandem oxidation and iodolactonization reaction of 2-O/N-tethered alkenyl benzaldehydes mediated by CuI and tertiarybutylhydro-peroxide in acetonitrile at 70 °C in moderate to good yields. The reaction involves initial oxidation of aldehyde to acid followed by iodolactonization. Terminal propargyl ether resulted in a mixture of mono- and diiodido-3-methylene-1,4-dioxepin-5-ones. The post-synthetic modification of the reaction products leads to the formation of corresponding thiocyanate, azide, thioether, and triazole derivatives.

A new [4 + 1]/[4 + 2]bicycliaztion strategy for accessing functionalized indeno[1,2-b]pyran-2-ones

A new base-promoted bicyclization strategy for the synthesis of functionalized indeno[1,2-b]pyran-2-ones has been established from readily accessible o-phthalaldehydes (OPA) and the preformed 1-arylethylidenemalononitriles.

Enantioselective addition of arylboronic acids to methyl 2-formylbenzoates by using a ruthenium/Me-BIPAM catalyst for synthesis of chiral 3-aryl-isobenzofuranones

[RuCl₂(p-cymene)]₂/Me-BIPAM and RuCl₂(PPh₃)₃/Me-BIPAM catalyst systems tolerate a variety of functional groups and give high yields with high enantioselectivities.

Radical scavenging and antioxidant activities of isocoumarins and a phthalide from the endophytic fungus Colletotrichum sp

Five known isocoumarins, monocerin (1), derivative 2, and fusarentin derivatives 3-5, and a new phthalide (6) were isolated from the endophytic fungus Colletotrichum sp. 2 selectively exhibited cytotoxic activity toward the HepG2 cell line. Compounds 2 and 4 scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals (IC(50) values of 23.4 and 16.4 μM, respectively) and inhibited superoxide anion radical formation (IC(50) values of 52.6 and 4.3 μM, respectively). The C-7 hydroxyl group in 2 and 4 might be important for radical scavenging activities. Isocoumarins 1-3 and phthalide 6 showed potent antioxidant activity.