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A de novo synthesis of a benzene ring allows for the preparation of a diverse range of heterocycles including indoles, benzofurans, benzothiophenes, carbazoles, and dibenzofurans from simple heteroaryl propargylic esters using a unified carbonylative benzannulation strategy. Multiple substituents can be easily introduced to the C4-C7 positions of indoles and related heterocycles. [ABSTRACT FROM AUTHOR]

By switching the position of the alkene and alkyne, a new type of 3-acyloxy-1,4-enyne (ACE) five-carbon building block was developed for Rh-catalyzed intramolecular [5+2] cycloaddition. An electron-withdrawing acyl group on the alkyne termini of the ACE was essential for a regioselective 1,2-acyloxy migration. This new method provided bicyclic [5.3.0]decatrienes that are different from previous methods because of the positions of the alkenes and the acyloxy group. Multiple mechanistic pathways become possible for this new [5+2] cycloaddition and they are investigated by computational studies. [ABSTRACT FROM AUTHOR]

A diverse range of indoles, benzofurans, benzothiophenes, carbazoles, and dibenzofurans is efficiently prepared which may contain functional groups prone to further derivatization. [ABSTRACT FROM AUTHOR]

The utility of the method is exemplified by the preparation of a photoelectrically interesting multiphenyl compound [cf. [ABSTRACT FROM AUTHOR]

A newly developed ligand consisting of phenanthroline and quinine in combination with copper is used as a chiral catalyst in the asymmetric Henry reaction giving products with good yields and high enantioselectivities. [ABSTRACT FROM AUTHOR]

Novel bipyridine substituted cinchona ligands are prepared and successfully applied to Cu(II)-catalyzed asymmetric Henry reactions. [ABSTRACT FROM AUTHOR]

The process applies the reaction of the carbenes with the electron-rich or neutral diynes or substituted enynes and affords 2-oxopyrrolidines and 3-azabicyclo[3.1.0]hexanes, respectively. [ABSTRACT FROM AUTHOR]