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A facile synthesis of 3-substituted 2-amidobenzofurans and 2-amidobenzothiophenes via electrophilic cyclization reaction of o-anisole- and o-thioanisole-substituted ynamides with I2, NBS and NCS was developed. The products 3-iodo-2-amidobenzofurans were further transferred into 3-aryl-, 3-alkynyl, and 3-vinyl-2-ami-dobenzofurans via Pd-catalyzed reactions such as Suzuki-Miyaura and Sonogashira cross-coupling reactions and the Heck reaction. [ABSTRACT FROM AUTHOR]

CuCl-catalyzed cyclization-dimerization reactions of 3-cyclopropylideneprop-2-en-1-ones provide an interesting route to benzofuran-7(3aH)-one derivatives with one highly strained three-membered ring and one four-membered ring via intramolecular cycloisomerization, sequential bimolecular [4 + 2] cycloaddition, opening of the oxa-bridge, and ring contraction. Furthermore, the reaction was monitored by NMR experiments to unveil some key intermediates. [ABSTRACT FROM AUTHOR]

We report in this paper an interesting sequential reaction involving sequential Sonogashira coupling, propargyl-allenyl isomerization, [4 + 2] cycloaddition and aromatization reaction, which provides a facile method for the synthesis of a variety of polycyclic isoindoline derivatives from easily accessible starting materials. [ABSTRACT FROM AUTHOR]

The manganese (III) acetate-mediated free radical cyclization of diarylmethvlenecyclopropa[b]naphthalenes with nudeophiles such as carboxylic acid and sulfonic acid provides an efficient method for the synthesis of 1,2-benzanthracenes in moderate to good yields under mild conditions. In addition, after several steps of simple and routine operations, the obtained 1,2-benzanthracenes bearing an acetoxy group could be easily converted to structurally more sophisticated 1,2-benzanthracene derivatives, which are not easily accessible yet potentially useful candidates for materials science. [ABSTRACT FROM AUTHOR]

An interesting sequential three-component reaction provides a facile synthesis of selenium/sulfur-substituted 3-oxabicyclo[4.2.0]octa-1(8),5-diene and tetrahydro-1H-isochromene from lithium alkylselenolates or alkylthiolates, 1-alkynylphosphine oxides, and aldehydes. The sequential reaction proceeds via a conjugate addition/condensation/elimination process to form the allene intermediate, which subsequently underwent [2 + 2] or [4 + 2] cyclization reaction to afford bicyclic frameworks. [ABSTRACT FROM AUTHOR]

An interesting sequential three-component copper-catalyzed coupling/propargyl-allenyl isomerization/[4 2] cyclization reaction, providing a facile synthesis of highly substituted tetrahydro-1H-isoindolones from conjugated vinylic alkynes, imines, and α,β-unsaturated enoic acid chlorides is reported. The most attractive feature of this transformation is that three stereogenic centers could be generated in one step with high diastereoselectivity. [ABSTRACT FROM AUTHOR]

A highly diastereo- and enantioselective silver-catalyzed azomethine ylide-imine (AYI) cycloaddition reaction of glycine aldimino esters with imines was developed in which the Xing-Phos-controlled syn-selective or DTBM-Segphos-induced anti-selective AYI cycloaddition reaction could be applied to the synthesis of a variety of stereodivergent 1-alkyl-2,5-substituted imidazolidines with high yields and excellent enantioselectivities (up to 99% ee) as well as good diastereoselectivities (up to 99:1 dr) under mild reaction conditions. [ABSTRACT FROM AUTHOR]